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 Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Document Title
2Mx16 bit CellularRAM
Revision History
Revision No.
0.0
History
Initial Draft
Draft Date
July 05,2007
Remark
Preliminary
Emerging Memory & Logic Solutions Inc.
4F Korea Construction Financial Cooperative B/D, 301-1 Yeon-Dong, Jeju-Si, Jeju-Do, Rep.of Korea Zip Code : 690-717 Tel : +82-64-740-1700 Fax : +82-64-740-1749~1750 / Homepage : www.emlsi.com 1 The attached datasheets are provided by EMLSI reserve the right to change the specifications and products. EMLSI will answer to your questions about device. If you have any questions, please contact the EMLSI office.
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
32Mb Async/Page/Burst CellularRAM
FEATURES
- Sigle device supports asynchrous, page and burst operation - Vcc, VccQ voltages: 1.7V~1.95V VCC 1.7V~1.95V VCCQ - Random access time: 70ns - Burst mode READ and WRITE access: 4, 8, 16, or 32 words, or continuous burst Burst wrap or sequential Max clock rate: 104 MHz (tCLK = 9.62ns) , 133MHz(tCLK = 7.5ns) Burst initial latency: 38.5ns (4 clocks) @ 104 MHz , 37.5ns(5 clocks) @ 133 MHz tACLK: 7ns @ 104 MHz , 5.5ns @ 133 MHz - Page mode READ access: Sixteen-word page size Interpage READ access : 70ns Intrapage READ access : 20ns - Low power consumption: Asynchronous READ: <25mA Intra page READ: <15mA Initial access, burst READ: (37.5ns [5 clocks] @ 133 MHz) <40mA Continuous burst READ: <35mA Deep power down: < 10uA(max.) - Low-power features On-chip temperature compensated self refresh (TCSR) Partial array refresh (PAR) Deep Power-down(DPD) mode
OPTIONS
- Configuration: 32Mb (2 megabit x 16) - Vcc core / VccQ I/O voltage supply: 1.8V - Timing: 70ns access - Frequency: 83 MHz, 104 MHz, 133 MHz - Standby current at 85C Low Low Power : 100A(max) Low Power : 120A(max) Standard : 140A(max) - Operating temperature range: Wireless -30C to +85C
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Table of Contents
Features ................................................................................................................................................................................. Options ............................................................................................................................................................................... General Description ................................................................................................................................................................ Functional Description ............................................................................................................................................................ Power-Up Initialization ....................................................................................................................................................... Bus Operating Modes ............................................................................................................................................................. Asynchronous Mode .......................................................................................................................................................... Page Mode READ Operation ............................................................................................................................................ Burst Mode Operation ........................................................................................................................................................ Mixed-Mode Operation ....................................................................................................................................................... WAIT Operation ................................................................................................................................................................. LB# / UB# Operation........................................................................................................................................................... Low-Power Operation......... .................................................................................................................................................... Standby Mode Operation ................................................................................................................................................... Temperature Compensated Refresh................................................................................................................................... Partial Array Refresh .......................................................................................................................................................... Deep Power-Down Operation............................................................................................................................................. Registers................................................................................................................................................................................. Access Using CRE ............................................................................................................................................................. Software Access ................................................................................................................................................................ Bus Configuration Register................................................................................................................................................. Burst Length (BCR[2:0]) Default = Continuous Burst ..................................................................................................... Burst Wrap (BCR[3]) Default = No Wrap ........................................................................................................................ Drive Strength (BCR[5:4]) Default = Outputs Use Half-Drive Strength ........................................................................... WAIT Configuration (BCR[8]) Default = WAIT Transitions One Clock Before Data Valid / Invalid................................... WAIT Polarity (BCR[10]) Default = WAIT Active HIGH................................................................................................... Latency Counter (BCR[13:11]) Default = Three Clock Latency .................................................................................... Initial Access Latency (BCR[14]) Default = Variable....................................................................................................... Operating Mode (BCR[15]) Default = Asynchronous Operation..................................................................................... Refresh Configuration Register........................................................................................................................................... Partial Array Refresh (RCR[2:0]) Default = Full Array Refresh ..................................................................................... Deep Power-Down (RCR[4]) Default = DPD Disabled ................................................................................................... Page Mode Operation (RCR[7]) Default = Disabled ...................................................................................................... Device Identification Register.............................................................................................................................................. Electrical Characteristics......................................................................................................................................................... Timing Requirements.............................................................................................................................................................. Timing Diagrams..................................................................................................................................................................... 2 2 6 9 9 10 10 11 12 15 15 15 16 16 16 16 16 17 17 21 22 23 23 24 24 24 25 25 26 27 28 28 28 28 29 31 35
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
List of Figures
Figure 1: Figure 2: Figure 3: Figure 4: Figure 5: Figure 6: Figure 7: Figure 8: Figure 9: Figure 10: Figure 11: Figure 12: Figure 13: Figure 14: Figure 15: Figure 16: Figure 17: Figure 18: Figure 19: Figure 20: Figure 21: Figure 22: Figure 23: Figure 24: Figure 25: Figure 26: Figure 27: Figure 28: Figure 29: Figure 30: Figure 31: Figure 32: Figure 33: Figure 34: Figure 35: Figure 36: Figure 37: Figure 38: Figure 39: Figure 40: Figure 41: Figure 42: Figure 43: Figure 44: Figure 45: Figure 46: Figure 47: Figure 48: Figure 49: Figure 50: Figure 51: Figure 52: Functional Block Diagram - 2 meg x 16 ............................................................................................................... Power-Up Initialization Timing ............................................................................................................................. READ Operation (ADV# LOW) ............................................................................................................................ WRITE Operation (ADV# LOW) ........................................................................................................................... Page Mode READ Operation (ADV# LOW) ......................................................................................................... Burst Mode READ (4-word burst)......................................................................................................................... Burst Mode WRITE (4-word burst)........................................................................................................................ Refresh Collision During Variable-Latency READ Operation ............................................................................... Wired or WAIT Configuration ............................................................................................................................. Configuration Register WRITE, Asynchronous Mode, Followed by READ ARRAY Operation ............................ Configuration Register WRITE, Synchronous Mode, Followed by READ ARRAY Operation .............................. Register READ, Asynchronous Mode, Followed by READ ARRAY Operation .................................................... Register READ, Synchronous Mode, Followed by READ ARRAY Operation ...................................................... Load Configuration Register ................................................................................................................................ Read Configuration Register ............................................................................................................................... Bus Configuration Register Definition .................................................................................................................. WAIT Configuration During Burst Operation ........................................................................................................ Latency Counter (Variable Initial Latency, No Refresh Collision) ......................................................................... Latency Counter (Fixed Latency) ........................................................................................................................ Refresh Configuration Register Mapping ............................................................................................................. AC Input/Output Reference Waveform ................................................................................................................ AC Output Load Circuit ........................................................................................................................................ Initialization Period .............................................................................................................................................. DPD Entry and Exit Timing Parameters ............................................................................................................... Asynchronous READ ........................................................................................................................................... Asynchronous READ Using ADV# ....................................................................................................................... PAGE MODE READ ........................................................................................................................................... Single-Access Burst READ Operation - Variable Latency .................................................................................... 4-Word Burst READ Operation - Variable Latency ............................................................................................... Single-Access Burst READ Operation - Fixed Latency ........................................................................................ 4-Word Burst READ Operation - Fixed Latency ................................................................................................... READ Burst Suspend .......................................................................................................................................... Burst READ at End-of-Row (Wrap off) ................................................................................................ Burst READ Row Boundary Crossing .................................................................................................................. CE# - Controlled Asychronous WRITE ................................................................................................................ LB#/UB# - Controlled Asychronous WRITE ......................................................................................................... WE# - Controlled Asychronous WRITE ............................................................................................................... Asynchronous WRITE Using ADV# ..................................................................................................................... Burst WRITE Operation - Variable Latency Mode ................................................................................................ Burst WRITE Operation - Fixed Latency Mode .................................................................................................... Burst WRITE at End-of-Row (Wrap off) ............................................................................................................... Burst WRITE Row Boundary Crossing ................................................................................................................ Burst WRITE Followed by Burst READ ................................................................................................................ Burst READ Interrupted by Burst READ or WRITE .............................................................................................. Burst WRITE Interrupted by Burst WRITE or READ - Variable Latency Mode ..................................................... Burst WRITE Interrupted by Burst WRITE or READ - Fixed Latency Mode ......................................................... Asynchronous WRITE Followed by Burst READ ................................................................................................. Asynchronous WRITE (ADV# LOW) Followed by Burst READ ........................................................................... Burst READ Followed by Asynchronous WRITE (WE# - Controlled) ................................................................... Burst READ Followed by Asynchronous WRITE Using ADV# ............................................................................. Asynchronous WRITE Followed by Asynchronous READ - ADV# LOW ............................................................. Asynchronous WRITE Followed by Asynchronous READ ................................................................................... 6 9 10 11 11 12 13 14 15 17 18 19 20 21 21 22 24 25 26 27 30 30 35 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
List of Tables
Table 1: Table 2: Table 3: Table 4: Table 5: Table 6: Table 7: Table 8: Table 9: Table 10: Table 11: Table 12: Table 13: Table 14: Table 15: Table 16: Table 17: PIN Descriptions ...................................................................................................................................................... Bus Operations ......................................................................................................................................................... Sequence and Burst Length ..................................................................................................................................... Drive Strength .......................................................................................................................................................... Variable Latency Configuration Codes...................................................................................................................... Fixed Latency Configuration Codes.......................................................................................................................... Address Patterns for PAR(RCR[4] =1)...................................................................................................................... Device Identification Register Mapping .................................................................................................................... Absolute Maximum Ratings ..................................................................................................................................... Electrical Characteristics and Operating Conditions ................................................................................................. Deep Power-Down Specifications ............................................................................................................................ Capacitance ............................................................................................................................................................. Asynchronous READ Cycle Timing Requirements ................................................................................................... Burst READ Cycle Timing Requirements ................................................................................................................. Asynchronous WRITE Cycle Timing Requirements ................................................................................................. Burst WRITE Cycle Timing Requirements ............................................................................................................... Initialization and DPD Timing Parameters ................................................................................................................ 7 8 23 24 25 26 28 28 29 29 30 30 31 32 33 34 35
5
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
General Description
CellularRAM products are high-speed, CMOS pseudo-static random access memory developed for low-power, portable applications. The 32Mb CellularRAM device has a DRAM core organized as 2 Meg x 16 bits. These devices include an industry-standard burst mode Flash interface that dramatically increase read/write bandwidth compared with other low-power SRAM or Pseudo SRAM offering. To operate seamlessly on a burst Flash bus, CellularRAM products incorporate a transparent self refresh mechanism. The hidden refresh requires no additional support from the system memory controller and has no significant impact on device READ/WRITE performance. Two user-accessible control registers define device operation. The bus configuration register (BCR) defines how the CellularRAM device interacts with the system memory bus and is nearly identical to its counterpart on burst mode Flash devices. The refresh configuration register (RCR) is used to control how refresh is performed on the DRAM array. These registers are automatically loaded with default settings during power-up and can be updated anytime during normal operation. Special attention has been focused on standby current consumption during self refresh. 32Mb CellularRAM products include three mechanisms to minimize standby current. Partial array refresh (PAR) enables the system to limit refresh to only that part of the DRAM array that contains essential data. Temperature compensated refresh (TCR) uses an onchip sensor to adjust the refresh rate to match the device temperature-the refresh rate decreases at lower temperatures to minimize current consumption during standby. Deep power-down (DPD) enables the system to halt the refresh operation altogether when no vital information is stored in the device. The system configurable refresh mechanisms are accessed through the RCR. This 32Mb CellularRAM devices is compliant with the industry-standard CellularRAM 1.5 feature set established by the CellularRAM Workgroup. It includes support for both variable and fixed latency, with three output-device drive-strength settings, additional wrap options, and a device ID register (DIDR).
Figure 1 : Functional Block Diagram - 2 meg x 16
A[20:0]
Address Decode Logic
Refresh Configuration Register (RCR)
2,048K x 16 DRAM MEMORY ARRAY
Input Output MUX and Buffers
DQ[7:0] DQ[15:8]
Device ID Register (DIDR)
Bus Configuration Register (BCR) CLK CE# WE# OE# ADV# CRE LB# UB# WAIT
Control Logic Internal External
Note: Functional block diagrams illustrate simplified device operation. See pin descriptions(Table 1); Bus operations table(Table 2); and timing diagrams for detailed information.
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Table 1 : PIN Descriptions Symbol Type Descriptions Address inputs: Inputs for addresses during READ and WRITE operations. Addresses are internally latched during READ and WRITE cycles. The address lines are also used to define the value to be loaded into the BCR or the RCR. Clock: Synchronizes the memory to the system operating frequency during synchronous operations. When configured for synchronous operation, the address is latched on the first rising CLK edge when ADV# is active. CLK is static LOW during asynchronous access READ and WRITE operations and during PAGE READ ACCESS operations. Address valid: Indiates that a valid address is present on the address inputs. Addresses can be latched on the rising edge of ADV# during asynchronous READ and WRITE operations. ADV# can be held LOW during asynchronous READ and WRITE operations. Control register enable: When CRE is HIGH, WRITE operations load the RCR or BCR, and READ operations access the RCR, BCR, or DIDR. Chip enable: Activates the device when LOW. When CE# is HIGH, the device is disabled and goes into standby or deep power-down mode. Output enable: Enables the output buffers when LOW. When OE# is HIGH, the output buffers are disabled. Write enable: Determines if a given cycle is a WRITE cycle. If WE# is LOW, the cycle is a WRITE to either a configuration register or to the memory array. Lower byte enable. DQ[7:0] Upper byte enable. DQ[15:8]
A[20:0]
Input
CLK (Note1)
Input
ADV# (Note1)
Input
CRE
Input
CE#
Input
OE#
Input
WE# LB# UB# DQ[15:0]
Input Input Input
Input/Output Data inputs/outputs. Wait: Provides data-valid feedback during burst READ and WRITE operations. The signal is gated by CE#. WAIT is used to arbitrate collisions between refresh and READ/WRITE operations. WAIT is also asserted at the end of a row unless wrapping within the burst length. WAIT is asserted and should be ignored during asynchronous and page mode operations. WAIT is High-Z when CE# is HIGH. Reserved for future use. Device power supply: (1.70V~1.95V) Power supply for device core operation. I/O power supply: (1.70V~1.95V) Power supply for input/output buffers. Vss must be connected to ground. VssQ must be connected to ground.
WAIT (Note1)
Output
RFU Vcc VccQ Vss VssQ
Supply Supply Supply Supply
Note: 1. When using asynchronous mode or page mode exclusively, CLK and ADV# inputs can be tied to Vss. WAIT will be asserted but should be ignored during asynchronous and page mode operations.
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Table 2: Bus Operations Asynchfonous Mode BCR[15]=1 Read Write Standby No operation Configuration register write Configuration register read DPD Burst Mode BCR[15]=0 Async read Async write Standby No operation Initial burst read Initial burst write Burst continue Burst suspend Configuration register write Configuration register read DPD Power Active Active Standby Idle Active CLK1 ADV# CE# L L L L L L L X X L L L H L L OE# L X X X H WE# H L X X L CRE L L L L H UB#/ LB# L L X X X WAIT2 Low-z Low-z High-z Low-z Low-z DQ[15:0]3 Data out Data in High-z X High-z Config. Reg.out High-z 7 Note 4 4 5, 6 4, 6
Active Deep Power-down Power Active Active Standby Idle Active Active Active Active Active
L
L
L
L
H
H
L
Low-z
L
X
H
X
X
X
X UB#/ LB# L L X X L X L X X
High-z
CLK1 ADV# CE# L L L L L L X X L L H X X L L L H L L L L L L
OE# L X X X X H X H H
WE# H L X X H L X X L
CRE L L L L L L X X H
WAIT2 Low-z Low-z High-z Low-z Low-z Low-z Low-z Low-z Low-z
DQ[15:0]3 Data out Data in High-z X X X Data out or Data in High-z High-z Config. Reg.out High-z
Note 4, 8 4 5, 6 4, 6 4, 9 4, 9 4, 9 4, 9 9, 10
Active Deep Power-down
L
L
L
H
H
L
Low-z
9, 10
L
X
H
X
X
X
X
High-z
7
Note: 1. CLK must be LOW during async read and async write modes; and to achieve standby power during standby and DPD modes. CLK must be static (HIGH or LOW) during burst suspend. 2. The WAIT polarity is configured through the bus configuration register (BCR[10]). 3. When LB# and UB# are in select mode (LOW), DQ[15:0] are affected. When only LB# is in select mode, DQ[7:0] are affected. When only UB# is in the select mode, DQ[15:8] are affected. 4. The device will consume active power in this mode whenever addresses are changed. 5. When the device is in standby mode, address inputs and data inputs/outputs are internally isolated from any external influence. 6. VIN = VccQ or 0V; all device pins must be static (unswitched) in order to achieve standby current. 7. DPD is initiated when CE# transitions from LOW to HIGH after writing RCR[4] to 0. DPD is maintained until CE# transitions from HIGH to LOW. 8. When the BCR is configured for sync mode, sync READ and WRITE, and async WRITE are supported by EMLSI. 9. Burst mode operation is initialized through the bus configuration register (BCR[15]). 10. Initial cycle. Following cycles are the same as BURST CONTINUE. CE# must stay LOW for the equivalent of a single-word burst (as indicated by WAIT).
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Functional Description
In general, CellularRAM devices are high-density alternatives to SRAM and Pseudo SRAM products, popular in low-power, portable applications. The 32Mb device contains a 33,554,432-bit DRAM core, organized as 2,097,152 addresses by 16 bits.The device implements the same high-speed bus interface found on burst mode Flash products. The CellularRAM bus interface supports both asynchronous and burst mode transfers. Page mode accesses are also included as a bandwidth-enhancing extension to the asynchronous read protocol.
Power-Up Initialization
32Mb CellularRAM products include an on-chip voltage sensor used to launch the power-up initialization process. Initialization will configure the BCR and the RCR with their default settings. (See Figure 16 and 20) Vcc and VccQ must be applied simultaneously. When they reach a stable level at or above 1.7V, the device will require 150s to complete its self-initialization process. During the initialization period, CE# should remain HIGH. When initialization is complete, the device is ready for normal operation. Figure 2: Power-Up Initialization Timing
Vcc=1.7V Vcc VccQ
tPU
150s
Device Initialization
Device ready for normal operation
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Bus Operating Modes
32Mb CellularRAM products incorporate a burst mode interface found on Flash products targeting low-power, wireless applications. This bus interface supports asynchronous, page mode, and burst mode read and write transfers. The specific interface supported is defined by the value loaded into the BCR. Page mode is controlled by the refresh configuration register (RCR[7]).
Asynchronous Mode
CellularRAM products power up in the asynchronous operating mode.This mode uses the industry- standard SRAM control bus (CE#, OE#, WE#, and LB#/UB#). READ operations (Figure 3) are initiated by bringing CE#, OE#, and LB#/UB# LOW while keeping WE# HIGH. Valid data will be driven out of the I/Os after the specified access time has elapsed. WRITE operations (Figure 4) occur when CE#, WE#, and LB#/UB# are driven LOW. During asychronous WRITE operations, the OE# level is a "Don't care", and WE# will override OE#. The data to be written is latched on the rising edge of CE#, WE#, or LB#/UB# (whichever occurs first). Asychronous operations (page mode disabled) can either use the ADV# input to latch the address, or ADV# can be driven LOW during the entire READ/ WRITE operation. During asychronous operation, the CLK input must be held static LOW. WAIT will be driven while the device is enabled and its state should be ignored. WE# LOW time must be limited to tCEM Figure 3: READ Operation (ADV# LOW)
CE#
OE#
WE# Address Address Valid
DATA
Data Valid
LB#/UB# tRC = READ Cycle Time Don't Care
Note: ADV# must remain Low for PAGE MODE operation.
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 4: WRITE Operation (ADV# LOW)
CE#
OE# < tCEM WE# Address Address Valid
DATA
Data Valid
LB#/UB# tWC = WRITE Cycle Time Don't Care
Page Mode Read Operation
Page mode is a performance-enhancing extension to the legacy asynchronous READ operation. In page-mode-capable products, an initial asynchronous read access is performed, then adjacent addresses can be read quickly by simply changing the low-order address. Addresses A[3:0] are used to determine the members of the 16-address CellularRAM page. Any change in addresses A[4] or higher will initiate a new tAA access time. Figure 5 shows the timing for a page mode access. Page mode takes advantage of the fact that adjacent addresses can be read in a shorter period of time than random addresses. WRITE operations do not include comparable page mode functionality. During asynchronous page mode operation, the CLK input must be held LOW. CE# must be driven HIGH upon completion of a page mode access. WAIT will be driven while the device is enabled and its state should be ignored. Page mode is enabled by setting RCR[7] to HIGH. ADV# must be driven LOW during all page mode READ accesses. Due to refresh considerations, CE# must not be LOW longer than tCEM. Figure 5: Page Mode READ Operation (ADV# LOW)
tCEM CE#
OE#
WE#
Address
Add0 tAA
Add1 Add2 Add3 tAPA D0 tAPA D1 tAPA D2 D3
DATA
LB#/UB# Don't Care
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Burst Mode Operation
Burst mode operations enable high-speed synchronous READ and WRITE operations. Burst operations consist of a multi-clock sequence that must be performed in an ordered fashion. After CE# goes LOW, the address to access is latched on the rising edge of the next clock that ADV# is LOW. During this first clock rising edge, WE# indicates whether the operation is going to be a READ (WE# = HIGH, Figure 6) or a WRITE (WE# = LOW, Figure 7). Figure 6: Burst Mode READ (4-word burst)
CLK
A[20:0]
Address Valid
ADV#
Latency Code 2 (3 clocks)
CE#
OE#
WE#
WAIT
DQ[15:0]
D0
D1
D2
D3
LB#/UB#
READ Burst Identified (WE# = HIGH)
Don't Care
Undefined
Note: Non-default BCR settings for burst mode READ (4-word burst): Fixed or variable latency; Latency code 2 (3 clocks); WAIT active LOW; WAIT asserted during delay. Diagram in the figure 6 is representative of variable latency with no refresh collision or fixed-latency access.
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 7: Burst Mode WRITE (4-word burst)
CLK
A[20:0]
Address Valid
ADV#
Latency Code 2(3 clocks)
CE#
OE#
WE#
WAIT
DQ[15:0]
D0
D1
D2
D3
LB#/UB#
WRITE Burst Identified (WE# = LOW)
Don't Care
Note: Non-default BCR settings for burst mode WRITE (4-word burst): Fixed or variable latency; latency code 2 (3 clocks); WAIT active LOW; WAIT asserted during delay.
The size of a burst can be specified in the BCR either as a fixed length or continuous. Fixed-length bursts consist of four, eight, sixteen, or thirty-two words. Continuous bursts have the ability to start at a specified address and burst to the end of the 128-word row. The latency count stored in the BCR defines the number of clock cycles that elapse before the initial data value is transferred between the processor and CellularRAM device. The initial latency for READ operations can be configured as fixed or variable (WRITE operations always use fixed latency). Variable latency allows the CellarRAM to be configured for minimum latency at high clock frequencies, but the controller must monitor WAIT to detect any conflict with refresh cycles. Fixed latency outputs the first data word after the worst-case access delay, including allowance for refresh collisions. The initial latency time and clock speed determine the latency count setting. Fixed latency is used when the controller cannot monitor WAIT. Fixed latency also provides improved performance at lower clock frequencies. The WAIT output asserts when a burst is initiated, and de-asserts to indicate when data is to be transferred into (or out of ) the memory. WAIT will again be asserted at the boundary of the 128-word row, unless wrapping within the burst length. To access other devices on the same bus without the timing penalty of the initial latency for a new burst, burst mode can be suspended. Bursts are suspended by stopping CLK. CLK can be stopped HIGH or LOW. If another device will use the data bus while the burst is suspended, OE# should be taken HIGH to disable the CellularRAM outputs; otherwise, OE# can remain LOW. Note that the WAIT output will continue to be active, and as a result no other devices should directly share the WAIT connection to the controller. To continue the burst sequence, OE# is taken LOW, then CLK is restarted after valid data is available on the bus. The CE# LOW time is limited by refresh considerations. CE# must not stay LOW longer than tCEM. If a burst suspension will cause CE# to remain LOW for longer than tCEM, CE# should be taken HIGH and the burst restarted with a new CE# LOW / ADV# LOW cycle.
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Mixed-Mode Operation
The device supports a combination of synchronous READ and asynchronous READ and WRITE operations when the BCR is configured for synchronous operation. (Some vendors also support asychronous READ.) The asynchronous READ and WRITE operations require that the clock (CLK) remain LOW during the entire sequence. The ADV# signal can be used to latch the target address, or it can remain LOW during the entire WRITE operation. CE# can remain LOW when transitioning between mixed-mode operations with fixed latency enabled; however, the CE# LOW time must not exceed tCEM. Mixed-mode operation facilitates a seamless interface to legacy burst mode Flash memory controllers. See Figure 47 for the "Asychronous WRITE Followed by Burst READ"timing diagram.
WAIT Operation
The WAIT output on a CellularRAM device is typically connected to a shared, system-level WAIT signal. (See Figure 9.) The shared WAIT signal is used by the processor to coordinate transactions with multiple memories on the synchronous bus. Figure 9: Wired or WAIT Configuration
CellularRAM
WAIT READY WAIT Processor Other Device WAIT Other Device
External Pull-Up/ Pull-Down Resistor
When a READ or WRITE operation has been initiated, WAIT goes active to indicate that the CellularRAM device requires additional time before data can be transferred. For READ operations, WAIT will remain active until valid data is output from the device. For WRITE operations, WAIT will indicate to the memory controller when data will be accepted into the CellularRAM device. When WAIT transitions to an inactive state, the data burst will progress on successive clock edges. During a burst cycle, CE# must remain asserted until the first data is valid. Bringing CE# HIGH during WAIT cycles may cause data corruption. When using variable initial access latency (BCR[14] = 0), the WAIT output performs an arbitration role for READ operations launched while an on-chip refresh is in progress. If a collision occurs, WAIT is asserted for additional clock cycles until the refresh has completed. (See Figure 8) When the refresh operation has completed, the READ operation will continue normally. WAIT will be asserted but should be ignored during asynchronous READ and WRITE, and page READ operations. By using fixed initial latency (BCR[14] = 1), this CellularRAM device can be used in burst mode without monitoring the WAIT signal. However, WAIT can still be used to determine when valid data is available at the start of the burst and at the end of row. If WAIT is not monitored, the controller must stop burst accesses at row boundaries on its own.
LB#/UB# Operation
The LB# enable and UB# enable signals support byte-wide data WRITEs. During WRITE operations, any disabled bytes will not be transferred to the RAM array and the internal value will remain unchanged. During an asynchronous WRITE cycle, the data to be written is latched on the rising edge of CE#, WE#, LB#, or UB#, whichever occurs first. LB# and UB# must be LOW during READ cycles. When both the LB# and UB# are disabled (HIGH) during an operation, the device will disable the data bus from receiving or transmitting data. Although the device will seem to be deselected, it remains in an active mode as long as CE# remains LOW.
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 8: Refresh Collision During Variable-Latency READ Operation
VIH CLK VIL VIH A[20:0] VIL VIH ADV# VIL VIH VIL VIH OE# VIL VIH VIL VIH LB#/UB# VIL VOH WAIT VOL VOH DQ[15:0] VOL
High-Z
Valid Address
CE#
WE#
D0
D1
D2
D3
Additional WAIT states inserted to allow refresh completion
Don't Care
Undefined
Note: Non-default BCR settings for refresh collision during variable-latency READ operation: Latency code 2 (3 clocks); WAIT active LOW; WAIT asserted during delay.
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Low-Power Operation
Standby Mode Operation
During standby, the device current consumption is reduced to the level necessary to perform the DRAM refresh operation. Standby operation occurs when CE# is HIGH. The device will enter a reduced power state upon completion of a READ or WRITE operation, or when the address and control inputs remain static for an extended period of time. This mode will continue until a change occurs to the address or control inputs.
Temperature Compensated Refresh
Temperature compensated refresh (TCR) allows for adequate refresh at different temperatures. This CellularRAM device includes an on-chip temperature sensor that automatically adjusts the refresh rate according to the operating temperature. The device continually adjusts the refresh rate to match that temperature.
Partial Array Refresh
Partial array refresh (PAR) restricts refresh operation to a portion of the total memory array. This feature enables the device to reduce standby current by refreshing only that part of the memory array required by the host system. The refresh options are full array, onehalf array, one-quarter array, one-eighth array, or none of the array. The mapping of these partitions can start at either the beginning or the end of the address map. (See Table 11) READ and WRITE operations to address ranges receiving refresh will not be affected. Data stored in addresses not receiving refresh will become corrupted. When re-enabling additional portions of the array, the new portions are available immediately upon writing to the RCR.
Deep Power-Down Operation
Deep power-down (DPD) operation disables all refresh-related activity. This mode is used if the system does not require the storage provided by the CellularRAM device. Any stored data will become corrupted when DPD is enabled. When refresh activity has been reenabled, the CellularRAM device will require 150s to perform an initialization procedure before normal operations can resume. During this 150s period, the current consumption will be higher than the specified standby levels, but considerably lower than the active current specification. DPD can be enabled by writing to the RCR using CRE or the software access sequence; DPD starts when CE# goes HIGH. DPD is disabled the next time CE# goes LOW and stays LOW for at least 10s.
16
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Registers
Two user-accessible configuration registers define the device operation. The bus configuration register (BCR) defines how the CellularRAM interacts with the system memory bus and is nearly identical to its counterpart on burst mode Flash devices. The refresh configuration register (RCR) is used to control how refresh is performed on the DRAM array. These registers are automatically loaded with default settings during power-up, and can be updated any time the devices are operating in a standby state. A DIDR provides information on the device manufacturer, CellularRAM generation, and the specific device configuration. The DIDR is read-only.
Access Using CRE
The registers can be accessed using either a synchronous or an asynchronous operation when the control register enable (CRE) input is HIGH. (See Figure 10 through 13) When CRE is LOW, a READ or WRITE operation will access the memory array. The configuration register values are written via addresses A[20:0]. In an asynchronous WRITE, the values are latched into the configuration register on the rising edge of ADV#, CE#, or WE#, whichever occurs first; LB# and UB# are "Don't Care". The BCR is accessed when A[19:18] are 10b; the RCR is accessed when A[19:18] are 00b. The DIDR is read when A[19:18] are 01b. For reads, address inputs other than A[19:18] are "Don't Care", and register bits 15:0 are output on DQ[15:0]. Immediately after performing a configuration register READ or WRITE operation, reading the memory array is highly recommended. Figure 10: Configuration Register WRITE, Asynchronous Mode, Followed by READ ARRAY Operation
A[20:0] (except A[19:18])
OPCODE tAVS
Select control register
Address tAVH Address
A[19:18]1
CRE
tAVS tAVH
ADV# tVP CE# Initiate control register access tCW OE# tWP WE#
Write address bus value to control register
tCPH
LB#/UB#
DQ[15:0]
Data Valid
Don't Care
Note: 1. A[19:18] = 00b to load RCR, and 10b to load BCR.
17
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 11: Configuration Register WRITE, Synchronous Mode, Followed by READ ARRAY Operation
CLK
Latch control register value
A[20:0] (except A[19:18])
OPCODE tSP tHD
Latch control register address
Address
A[19:18]
2
Address tSP tHD
CRE tSP ADV# tCBPH Note 3
tHD
tCSP CE#
OE# tSP tHD WE#
LB#/UB# tCEW WAIT
High-Z High-Z
DQ[15:0]
Data Valid Don't Care
Note: 1. Non-default BCR settings for synchronous mode configuration register WRITE followed by READ ARRAY operation: Latency code 2 (3 clocks), WAIT active LOW, WAIT asserted during delay. 2. A[19:18] = 00b to load RCR, and 10b to load BCR. 3. CE# must remain LOW to complete a burst-of-one WRITE. WAIT must be monitored; additional WAIT cycles caused by refresh collisions require a corresponding number of additional CE# LOW cycles.
18
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 12: Register READ, Asynchronous Mode, Followed by READ ARRAY Operation
A[20:0] (except A[19:18]) tAVS
Select Register
Address tAVH Address tAA tAVH
A[19:18]1
CRE
tAVS tAA
ADV# tVP CE# tAADV tCPH
Initiate register access tCO tHZ
OE# tOE WE# tOLZ tLZ LB#/UB# tLZ DQ[15:0] CR Valid Data Valid tBHZ tBA tOHZ
Don't Care
Undefined
Note: A[19:18] = 00b to read RCR, 10b to read BCR, and 01b to read DIDR.
19
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 13: Register READ, Synchronous Mode, Followed by READ ARRAY Operation (WE# HIGH)
CLK
Latch control register value
A[20:0] (except A[19:18]) tSP A[19:18]2 tSP CRE tHD tSP ADV# tHD tCSP CE# tABA
Note 3 Latch control register address
Address
Address tHD
tCBPH
tHZ
OE# tOHZ WE# tSP LB#/UB# tCW WAIT
High-Z
tBOE
tHD
tACLK tOLZ tKOH
High-Z
DQ[15:0]
CR Valid
Data Valid
Don't Care
Undefined
Note: 1. Non-default BCR settings for synchronous mode register READ followed by READ ARRAY operation: Latency code 2 (3 clocks); WAIT active LOW; WAIT asserted during delay. 2. A[19:18] = 00b to read RCR, 10b to read BCR, and 01b to read DIDR. 3. CE# must remain LOW to complete a burst-of-one READ. WAIT must be monitored; additional WAIT cycles caused by refresh collisions require a corresponding number of additional CE# LOW cycles.
20
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Software Access
Software access of the registers uses a sequence of asynchronous READ and asynchronous WRITE operations. The contents of the configuration registers can be modified and all registers can be read using the software sequence. The configuration registers are loaded using a four-step sequence consisting of two asynchronous READ operations followed by two asynchronous WRITE operations.(See Figure 14.) The read sequence is virtually identical except that an asynchronous READ is performed during the fourth operation. (See Figure 15.) The address used during all READ and WRITE operations is the highest address of the CellularRAM device being accessed (1FFFFFh); the contents of this address are not changed by using this sequence. The data value presented during the third operation (WRITE) in the sequence defines whether the BCR, RCR, or the DIDR is to be accessed. If the data is 0000h, the sequence will access the RCR; if the data is 0001h, the sequence will access the BCR; if the data is 0002h, the sequence will access the DIDR. During the fourth operation, DQ[15:0] transfer data in to or out of bits 15:0 of the registers. The use of the software sequence does not affect the ability to perform the standard (CRE-controlled) method of loading the configuration registers. However, the software nature of this access mechanism eliminates the need for CRE. If the software mechanism is used, CRE can simply be tied to Vss. The port line often used for CRE control purposes is no longer required. Figure 14: Load Configuration Register
READ Address ADDRESS Max READ ADDRESS Max WRITE ADDRESS Max WRITE ADDRESS Max
CE#
OE#
WE#
LB#/UB#
DATA
XXXXh
XXXXh RCR : 0000h BCR : 0001h
CR Value In
Don't Care
Figure 15: Read Configuration Register
READ Address ADDRESS Max READ ADDRESS Max WRITE ADDRESS Max READ ADDRESS Max
CE#
OE#
WE#
LB#/UB#
DATA
XXXXh
XXXXh RCR : 0000h BCR : 0001h DIDR : 0002h
CR Value In
Don't Care
21
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Bus Configuration Register
The BCR defines how the CellularRAM device interacts with the system memory bus. Page mode operation is enabled by a bit contained in the RCR. Figure 16 describes the control bit BCR. At power-up, the BCR is set to 9D1Fh. The BCR is accessed with CRE HIGH and A[19:18] = 10b, or through the register access software sequence with DQ = 0001h on the third cycle. Figure 16: Bus Configuration Register Definition
A[20] A[19:18] A[17:16] A15 A14 A13 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0
20 Reserved
19-18 Register Select
17-16 Reserved
15
14
13
12 Latency Counter
11
10
9
8
7
6
5
4
3
2
1
0
Operating Initial Mode Latency
WAIT WAIT Drive Burst Burst Reserved Reserved Reserved Polarity Configuration(WC) Strength Wrap(BW)* Length(BL)*
All must be set to "0" Must be set to "0"
Must be set to "0"
Must be set to "0" Must be set to "0"
BCR[14] 0 1
Initial Access Latency Variable (default) Fixed
BCR[3] 0 1
Burst Wrap (Note 1)
Burst wraps within the burst length Burst no wrap (default)
BCR[5] BCR[4] Drive Strength BCR[13] BCR[12] BCR[11] 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 Latency Counter Code 8 Code 1 - Reserved Code 2 Code 3 (default) Code 4 Code 5 Code 6 Code 7 - Reserved BCR[10] 0 1 BCR[15] 0 1 Operating Mode
Synchronous burst access mode Asynchronous access mode (default)
0 0 1 1
0 1 0 1
Full 1/2 (default) 1/4 Reserved
BCR[8] 0 1 WAIT Polarity Active LOW Active HIGH (default)
WAIT Configuration
Asserted during delay Asserted one data before delay(default)
BCR[2] BCR[1] BCR[0] Burst Length (Note 1) 0 0 0 1 1 0 1 1 0 1 Others 1 0 1 0 1
4 words 8 words 16 words 32 words Continuous burst (default) Reserved
BCR[19] BCR[18] Register Select 0 1 0 0 0 1 Select RCR Select BCR Select DIDR
Note: 1. Burst wrap and length apply to both READ and WRITE operations.
22
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Burst Length (BCR[2:0]) Default = Continuous Burst
Burst lengths define the number of words the device outputs during burst READ and WRITE operations. The device supports a burst length of 4, 8, 16, or 32 words. The device can also be set in continuous burst mode where data is accessed sequentially up to the end of row.
Burst Wrap (BCR[3]) Default = No Wrap
The burst-wrap option determines if a 4, 8, 16, or 32 word READ or WRITE burst wraps within the burst length, or steps through sequential addresses. If the wrap option is not enabled, the device accesses data from sequential addresses up to the end of the row.
Table 3: Sequence and Burst Length BURST Wrap Starting Address 4 Word Burst Length Linear
0-1-2-3 1-2-3-0 2-3-0-1 3-0-1-2
8 Word Burst Length Linear
0-1-2-3-4-5-6-7 1-2-3-4-5-6-7-0 2-3-4-5-6-7-0-1 3-4-5-6-7-0-1-2 4-5-6-7-0-1-2-3 5-6-7-0-1-2-3-4 6-7-0-1-2-3-4-5 7-0-1-2-3-4-5-6
16 Word Burst Length Linear
0-1-2-3-4-5-6-7-8-9-10-11-12-13-14-15 1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-0 2-3-4-5-6-7-8-9-10-11-12-13-14-15-0-1 3-4-5-6-7-8-9-10-11-12-13-14-15-0-1-2 4-5-6-7-8-9-10-11-12-13-14-15-0-1-2-3 5-6-7-8-9-10-11-12-13-14-15-0-1-2-3-4 6-7-8-9-10-11-12-13-14-15-0-1-2-3-4-5 7-8-9-10-11-12-13-14-15-0-1-2-3-4-5-6 ... 14-15-0-1-2-3-4-5-6-7-8-9-10-11-12-13 15-0-1-2-3-4-5-6-7-8-9-10-11-12-13-14
32 Word Burst Length Linear
0-1-2 ... 29-30-31 1-2-3 ... 30-31-0 2-3-4 ... 31-0-1 3-4-5 ... 0-1-2 4-5-6 ... 1-2-3 5-6-7 ... 2-3-4 6-7-8 ... 3-4-5 7-8-9 ... 4-5-6 ... 14-15-16-...-11-12-13 15-16-17...-12-13-14 ... 30-31-0-...-27-28-29 31-0-1-... -28-29-30
Continuous Burst Linear
0-1-2-3-4-5-6-... 1-2-3-4-5-6-7-... 2-3-4-5-6-7-8-... 3-4-5-6-7-8-9-... 4-5-6-7-8-9-10-... 5-6-7-8-9-10-11-... 6-7-8-9-10-11-12-... 7-8-9-10-11-12-13-... ... 14-15-16-17-18-19-20-... 15-16-17-18-19-20-21-... ... 30-31-32-33-34-... 31-32-33-34-35-... 0-1-2-3-4-5-6-... 1-2-3-4-5-6-7-... 2-3-4-5-6-7-8-... 3-4-5-6-7-8-9-... 4-5-6-7-8-9-10-... 5-6-7-8-9-10-11-... 6-7-8-9-10-11-12-... 7-8-9-10-11-12-13-... ... 14-15-16-17-18-19-20-... 15-16-17-18-19-20-21-... ... 30-31-32-33-34-35-36-... 31-32-33-34-35-36-37-...
BCR[3] Wrap Decimal
0 1 2 3 4 5 6
0
Yes
7 ... 14 15 ... 30 31 0 1 2 3 4 5 6 0-1-2-3 1-2-3-4 2-3-4-5 3-4-5-6
0-1-2-3-4-5-6-7 1-2-3-4-5-6-7-8 2-3-4-5-6-7-8-9 3-4-5-6-7-8-9-10 4-5-6-7-8-9-10-11 5-6-7-8-9-10-11-12 6-7-8-9-10-11-12-13
0-1-2-3-4-5-6-7-8-9-10-11-12-13-14-15 1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16 2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17 3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18 4-5-6-7-8-9-10-11-12-13-14-15-16-17-18-19 5-6-7-8-9-10-11-12-13-14-15-16-17-18-19-20 6-7-8-9-10-11-12-13-14-15-16-17-18-19-20-21 ... 14-15-16-17-18-...-23-24-25-26-27-28-29 15-16-17-18-19-...-24-25-26-27-28-29-30
0-1-2-...-29-30-31 1-2-3-...-30-31-32 2-3-4-...-31-32-33 3-4-5-...-32-33-34 4-5-6-...-33-34-35 5-6-7-...-34-35-36 6-7-8-...-35-36-37 7-8-9-...-36-37-38 ... 14-15-16-...43-44-45 15-16-17-...-44-45-46 ... 30-31-32-...-59-60-61 31-32-33-...-60-61-62
1
No
7 ... 14 15 ... 30 31
7-8-9-10-11-12-13-14 7-8-9-10-11-12-13-14-15-16-17-18-19-20-21-22
23
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Drive Strength (BCR[5:4]) Default = Outputs Use Half-Drive Strength
The output driver strength can be altered to full, one-half, or one-quarter strength to adjust for different data bus loading scenarios. The reduced-strength options are intended for stacked chip (Flash + CelllularRAM) environments when there is a dedicated memory bus. The reduced-drive-strength option minimizes the noise generated on the data bus during READ operations. Full output drive strength should be selected when using a discrete CellularRAM device in a more heavily loaded data bus environment. Outputs are configured at half-drive strength during testing. See Table 4 for additional information. Table 4: Drive Strength BCR[5] 0 0 1 1 BCR[4] 0 1 0 1 Drive Strength Full 1/2 (default) 1/4 Impedance Typ ( 25~30 50 100 Reserved ) Use Recommendation CL = 30pF to 50pF CL = 15pF to 30pF 104 MHz at light load CL = 15pF or lower
WAIT Configuration (BCR[8]) Default = WAIT Transitions One Clock Before Data Valid/Invalid
The WAIT configuration bit is used to determine when WAIT transitions between the asserted and the de-asserted state with respect to valid data presented on the data bus. The memory controller will use the WAIT signal to coordinate data transfer during synchronous READ and WRITE operations. When BCR[8] = 0, data will be valid or invalid on the clock edge immediately after WAIT transitions to the de-asserted or asserted state, respectively. When A8 = 1, the WAIT signal transitions one clock period prior to the data bus going valid or invalid. (See Figure 17.)
WAIT Polarity (BCR[10]) Default = WAIT Active HIGH
The WAIT polarity bit indicates whether an asserted WAIT output should be HIGH or LOW. This bit will determine whether the WAIT signal requires a pull-up or pull-down resistor to maintain the de-asserted state. Figure 17: WAIT Configuration During Burst Operation
CLK BCR[8] = 0 WAIT Data valid in current cycle BCR[8] = 1 WAIT Data valid in next cycle
DQ[15:0]
D0
D1
D2
D3
End of row
Don't Care
Note: Non-default BCR setting: WAIT active LOW.
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Latency Counter (BCR[13:11]) Default = Three Clock Latency
The latency counter bits determine how many clocks occur between the beginning of a READ or WRITE operation and the first data value transferred. For allowable latency codes, see Tables 5 and 6, respectively, and Figures 18 and 19, respectively.
Initial Access Latency (BCR[14]) Default = Variable
Variable initial access latency outputs data after the number of clocks set by the latency counter. However, WAIT must be monitored to detect delays caused by collisions with refresh operations. Fixed initial access latency outputs the first data at a consistent time that allows for worst-case refresh collisions. The latency counter must be configured to match the initial latency and the clock frequency. It is not necessary to monitor WAIT with fixed initial latency. The burst begins after the number of clock cycles configured by the latency counter. (See Table 6 and Figure 19) Table 5: Variable Latency Configuration Codes BCR[13:11] 010 011 100 Others Latency Configuration Code 2 (3 clocks) 3 (4 clocks)-default 4 (5 clocks) Reserved Latency 1 Normal 2 3 4 Refresh Collision 4 6 8 Max Input CLK Frequency (MHz) 133 66(15ns) 104 66(15ns) 83 52(19.2ns) 83(12ns) -
104(9.62ns) 104(9.62ns) 133(7.5ns) -
Note: 1. Latency is the number of clock cycles from the initiation of a burst operation until data appears. Data is transferred on the next clock cycle.
Figure18: Latency Counter (Variable Initial Latency, No Refresh Collision)
VIH
CLK
VIL VIH
A[20:0]
VIL VIH
Valid Address
ADV#
VIL
DQ[15:0]
VOH VOL
Code 2
Valid Output (default)
Valid Output Valid Output
Valid Output Valid Output
Valid Output Valid Output Don't Care
Valid Output Valid Output Undefined
DQ[15:0]
VOH VOL
Code 3
25
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Table 6: Fixed Latency Configuration Codes BCR[13:11] 010 011 100 101 110 000 others Latency Configuration Code 2 (3 clocks) 3 (4 clocks)-default 4 (5 clocks) 5 (6 clocks) 6 (7 clocks) 8 (9 clocks) Reserved Max Input CLK Frequency (MHz) Latency Count (N) 2 3 4 5 6 8 -133 33(30ns) 52(19.2ns) 66(15ns) 75(13.3ns) 104(9.62ns) 133(7.5ns) 104 33(30ns) 52(19.2ns) 66(15ns) 75(13.3ns) 104(9.62ns) 83 33(30ns) 52(19.2ns) 66(15ns) 75(13.3ns) 83(12ns) -
Figure 19: Latency Counter (Fixed Latency)
N-1 Cycles CLK
VIH VIL VIH
Cycle N
tAA Valid Address tAADV
A[20:0]
VIL VIH
ADV#
VIL VIH
tCO tACLK Valid Output tSP tHD Valid Output Valid Output Valid Output Valid Output
CE#
VIL VOH
DQ[15:0] (READ) V OL DQ[15:0] (WRITE) V OL
VOH
Valid Input
Valid Input
Valid Input
Valid Input
Valid Input Undefined
Burst Identified (ADV# = LOW)
Don't Care
Operating Mode (BCR[15]) Default = Asynchronous Operation
The operating mode bit selects either synchronous burst operation or the default asynchronous mode of operation.
26
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Refresh Configuration Register
The refresh configuration register (RCR) defines how the CellularRAM device performs its transparent self refresh. Altering the refresh parameters can dramatically reduce current consumption during standby mode. Page mode control is also embedded into the RCR. Figure 20 describes the control bits used in the RCR. At power-up, the RCR is set to 0010h. The RCR is accessed with CRE HIGH and A[19:18] = 00b; or through the register access software sequence with DQ = 0000h on the third cycle. Figure 20: Refresh Configuration Register Mapping
Address Bus A[20] A[19:18] A[17:8] A7 A6 A5 A4 A3 A2 A1 A0
20 Reserved
19-18 Register Select
17-8 Reserved
7 Page
6 Reserved
5
4
3 Reserved
2
1 PAR
0
DPD
All must be set to "0"
All must be set to "0"
Setting is ignored (Default 00b)
Must be set to "0"
RCR[19] 0 1 0
RCR[18] 0 0 1
Register Select Select RCR Select BCR Select DIDR
RCR[2] 0 0 0 0 1
RCR[1] 0 0 1 1 0 0 1 1
RCR[0] 0 1 0 1 0 1 0 1
Refresh Coverage Full array (default) Bottom 1/2 array Bottom 1/4 array Bottom 1/8 array None of array Top 1/2 array Top 1/4 array Top 1/8 array
RCR[7] 0 1
Page Mode Enable/Disable Page Mode Disable (default) Page Mode Enable
1 1 1
RCR[4] 0 1
Deep Power-Down DPD Enable DPD Disable (default)
27
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Partial Array Refresh (RCR[2:0] Default = Full Array Refresh
The PAR bits restrict refresh operation to a portion of the total memory array. This feature allows the device to reduce standby current by refreshing only that part of the memory array required by the host system. The refresh options are full array, one-half array, onequarter array, one-eighth array, or none of the array. The mapping of these partitions can start at either the beginning or the end of the address map. Table 7: Address Patterns for PAR (RCR[4] = 1) RCR[2] 0 0 0 0 1 1 1 1 RCR[1] 0 0 1 1 0 0 1 1 RCR[0] 0 1 0 1 0 1 0 1 Active Section Full Die One-half die One-quarter of die One-eighth of die None of die One-half of die One-quarter of die One-eighth of die Address Space 000000h-1FFFFFh 000000h-0FFFFFh 000000h-07FFFFh 000000h-03FFFFh 0 100000h-1FFFFFh 180000h-1FFFFFh 1C0000h-1FFFFFh Size 2 Meg x 16 1 Meg x 16 512 K x 16 256 K x 16 0 Meg x 16 1 Meg x 16 512 K x 16 256 K x 16 Density 32Mb 16Mb 8Mb 4Mb 0Mb 16Mb 8Mb 4Mb
Deep Power-Down (RCR[4]) Default = DPD Disabled
The deep power-down bit enables and disables all refresh-related activity. This mode is used if the system does not require the storage provided by the CellularRAM device. Any stored data will become corrupted when DPD is enabled. When refresh activity has been re-enabled, the CellularRAM device will require 150s to perform an initialization procedure before normal operations can resume. Deep power-down is enabled by setting RCR[4] = 0 and taking CE# HIGH. DPD can be enabled using CRE or the software sequence to access the RCR. Taking CE# LOW for at least 10s disables DPD and sets RCR[4] = 1; it is not necessary to write to the RCR to disable DPD. BCR and RCR values (other than RCR[4]) are preserved during DPD.
Page Mode Operation (RCR[7]) Default = Disabled
The page mode operation bit determines whether page mode is enabled for asynchronous READ operations. In the power-up default state, page mode is disabled.
Device Identification Register
The DIDR provides information on the device manufacturer, CellularRAM generation, and the specific device configuration. Table 8 describes the bit fields in the DIDR. This register is read-only. The DIDR is accessed with CRE HIGH and A[19:18] = 01b, or through the register access software sequence with DQ = 0002h on the third cycle. Table 8: Device Identification Register Mapping Bit Field
Field name
DIDR[15]
Row Length Length Bit Setting 0b
DIDR[14:11]
Device version Version 2nd Bit Setting 0001b
DIDR[10:8]
Device density Density 32Mb Bit Setting 001b
DIDR[7:5]
CellularRAM generation Generation CR 1.5 Bit Setting 010b
DIDR[4:0]
Vendor ID Vendor EMLSI Bit Setting 01010b
Options
128 words
28
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Electrical Characteristics
Table 9: Absolute Maximum Ratings Parameter
Voltage to any pin except Vcc, VccQ relative to Vss Voltage on Vcc supply relative to Vss Voltage on VccQ supply relative to Vss Storage temperature (plastic) Operating temperature (case) Wireless Soldering temperature and time 10s (solder ball only)
Rating
-0.50V to VccQ + 0.3V -0.2V to +2.45V -0.2V to +2.45V -55C to +150C -30C to +85C +260C
Stresses greater than those listed may cause permanent damage to the device. This is a stress rating only, and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability.
Table 10: Electrical Characteristics and Operating Conditions Wireless Temperature (-30C < TC < +85C) Description
Supply voltage I/O supply voltage Input high voltage Input low voltage Output high voltage Output low voltage Input leakage current Output leakage current IOH = -0.2mA IOL = +0.2mA VIN = 0 to VccQ OE# = VIH or chip disabled
Conditions
Vcc VccQ VIH VIL VOH VOL ILI ILO
Symbol
Min
1.7 1.7 VccQ - 0.4 -0.20 0.80 VccQ
Max
1.95 1.95 VccQ + 0.2 0.4
Unit
V V V V V
Note
1 2 3 3
0.20 VccQ 1 1
V
A A Unit
mA mA mA mA mA mA mA mA mA mA mA 4 4 4
Operating current
Asynchronous random READ/WRITE Asynchronous PAGE READ Initial access burst READ/WRITE
Conditions
ICC1 ICC1P
Symbol
70ns 70ns 133MHz ICC2 104MHz 83MHz 133MHz
Typ
Max
25 15 40 35 30 35 30 25 40 35 30 140 120 100
Note
4 4
VIN = VccQ or 0V chip enabled, IOUT = 0 Continuous burst READ ICC3R
104MHz 83MHz 133MHz
Continuous burst WRITE
ICC3W
104MHz 83MHz Standard
A A A
5, 6
Standby current
VIN = VccQ or 0V, CE# = VccQ
ISB
Low Power LowLowPower
Note: 1. Input signals may overshoot to VccQ + 1.0V for periods less than 2ns during transitions. 2. Input signals may undershoot to Vss - 1.0V for periods less than 2ns during transitions. 3. BCR[5:4] = 01b (default setting of one-half drive strength). 4. This parameter is specified with the outputs disabled to avoid external loading effects. The user must add the current required to drive output capacitance expected in the actual system. 5. ISB (max) values measured with PAR set to FULL ARRAY and at +85C. In order to achieve low standby current, all inputs must be driven to either VccQ or Vss. ISB might be slightly higher for up to 500ms after power-up, or when entering standby mode. 6. ISB (typ) is the average ISB at 25C and Vcc = VccQ = 1.8V. This parameter is verified during characterization, and is not 100% tested.
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Table 11: Deep Power-Down Specifications Description
Deep Power-Down
Conditions
VIN = VccQ or 0V; Vcc, VccQ = 1.95V; +85C
Symbol
IZZ
Typ
-
Max
10
Unit A
Note: Typical (TYP) IZZ value is tested at Vcc=1.8V, TA=25C and not guaranteed.
Table 12: Capacitance Description
Input Capacitance Input/Output Capacitance(DQ) Tc = +25C; f = 1 MHz; VIN = 0V
Conditions
Symbol
CIN CIO
Min
2.0 3.5
Max
6 6
Unit
pF pF
Note
1 1
Note: These parameters are verified in device characterization and are not 100% tested.
Figure 21: AC Input/Output Reference Waveform
VccQ Input1 VssQ VccQ/22 Test Points VccQ/23 Output
Note: 1. AC test inputs are driven at VccQ for a logic 1 and VssQ for a logic 0. Input rise and fall times (10% to 90%) <1.6ns. 2. Input timing begins at VccQ/2. 3. Output timing ends at VccQ/2.
Figure 22: AC Output Load Circuit
Test Points 50-Ohm
DUT
VccQ/2 30pF
Note: All tests are performed with the outputs configured for default setting of half drive strength (BCR[5:4] = 01b).
30
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
TIMING REQUIREMENTS
Table 13: Asynchronous READ Cycle Timing Requirements All tests performed with outputs configured for default setting of half drive strength, (BCR[5:4] = 01b). Parameter
Address access time ADV# access time Page access time Address hold from ADV# HIGH Address setup to ADV# HIGH LB#/UB# access time LB#/UB# disable to DQ High-Z output LB#/UB# enable to Low-Z output Maximum CE# pulse width CE# LOW to WAIT valid Chip select access time CE# LOW to ADV# HIGH Chip disable to DQ and WAIT High-Z output Chip enable to Low-Z output Output enable to valid output Output hold from address change Output disable to DQ High-Z output Output enable to Low-Z output Page READ cycle time READ cycle time ADV# pulse width LOW
Symbol
tAA tAADV tAPA tAVH tAVS tBA tBHZ tBLZ tCEM tCEW tCO tCVS tHZ tLZ tOE tOH tOHZ tOLZ tPC tRC tVP
70ns Min
2 5 10 1 7 10 5 3 20 70 5
Max
70 70 20 70 8 4 7.5 70 8 20 8 -
Unit
ns ns ns ns ns ns ns ns
Note
4
1 2 3
s
ns ns ns ns ns ns ns ns ns ns ns ns
1 2
1 2 4
Note: 1. The High-Z timings measure a 100mV transition from either VOH or VOL toward VccQ/2. 2. The Low-Z timings measure a 100mV transition away from the High-Z (VccQ/2) level toward either VOH or VOL. 3. Page mode enabled only. 4. Contact EMLSI for specific timing.
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Table 14: Burst READ Cycle Timing Requirements All tests performed with outputs configured for default setting of half drive strength, (BCR[5:4] = 01b). Parameter
Address access time (fixed latency) ADV# access time (fixed latency) Burst to READ access time (variable latency) CLK to output delay Address hold from ADV# HIGH(fixed latency) Burst OE# LOW to output delay CE# HIGH between subsequent burst or mixed mode operations Maximum CE# pulse width CE# or ADV# LOW to WAIT valid CLK period Chip select access time (fixed latency) CE# setup time to active CLK edge Hold time from active CLK edge Chip disable to DQ and WAIT High-Z output CLK rise or fall time CLK to WAIT valid Output HOLD from CLK CLK HIGH or LOW time Output disable to DQ High-Z output Output enable to Low-Z output Setup time to active CLK edge
Symbol
tAA tAADV tABA tACLK tAVH tBOE tCBPH tCEM tCEW tCLK tCO tCSP tHD tHZ tKHKL tKHTL tKOH tKP tOHZ tOLZ tSP 2 5 1
133MHz
Min Max 70 70 35.5 5.5 20 4 7.5 70 7 1.2 5.5 7 -
104MHz
Min 2 5 1 9.62 3 2 2 3 3 3 Max 70 70 35.9 7 20 4 7.5 70 8 1.6 7 8 -
83MHZ
Min 2 6 1 12 4 2 2 4 3 3 Max 70 70 45 9 20 4 7.5 70 8 1.8 9 8 -
Unit Note
ns ns ns ns ns ns ns 1 1
s
ns ns ns ns ns ns ns ns ns ns ns ns ns
7.5 2.5 1.5 2 3 3 2
3
2 3
Note: 1. A refresh opportunity must be provided every tCEM. A refresh opportunity is satisfied by either of the following two conditions: a) clocked CE# HIGH, or b) CE# HIGH for longer than 15ns. 2. The High-Z timings measure a 100mV transition from either VOH or VOL toward VccQ/2. 3. The Low-Z timings measure a 100mV transition away from the High-Z (VccQ/2) level toward either VOH or VOL.
32
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Table 15: Asynchronous WRITE Cycle Timing Requirements Parameter
Address and ADV# LOW setup time Address HOLD from ADV# going HIGH Address setup to ADV# going HIGH Address valid to end of WRITE LB#/UB# select to end of WRITE CE# LOW to WAIT valid CE# HIGH between subsequent async operations CE# LOW to ADV# HIGH Chip enable to end of WRITE Data HOLD from WRITE time Data WRITE setup time Chip disable to WAIT High-Z output Chip enable to Low-Z output End WRITE to Low-Z output ADV# pulse width ADV# setup to end of WRITE WRITE cycle time WRITE to DQ High-Z output WRITE pulse width WRITE pulse width HIGH WRITE recovery time
Symbol
tAS tAVH tAVS tAW tBW tCEW tCPH tCVS tCW tDH tDW tHZ tLZ tOW tVP tVS tWC tWHZ tWP tWPH tWR
70ns Min
0 2 5 70 70 1 5 7 70 0 20 10 5 5 70 70 45 10 0
Max
7.5 8 8 -
Unit
ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns
Note
1 2 2
1 3
Note: 1. The High-Z timings measure a 100mV transition from either VOH or VOL toward VccQ/2. 2. The Low-Z timings measure a 100mV transition away from the High-Z (VccQ/2) level toward either VOH or VOL. 3. WE# Low time must be limited to tCEM (4s).
33
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Table 16: Burst WRITE Cycle Timing Requirements Parameter
Address and ADV# LOW setup time Address HOLD from ADV# HIGH(fixed latency) CE# HIGH between subsequent burst or mixed mode operations Maximum CE# pulse width CE# LOW to WAIT valid Clock period CE# setup to CLK active edge Hold time from active CLK edge Chip disable to WAIT High-Z output CLK rise or fall time Clock to WAIT valid CLK HIGH or LOW time Setup time to activate CLK edge
Symbol
tAS tAVH tCBPH tCEM tCEW tCLK tCSP tHD tHZ tKHKL tKHTL tKP tSP 0 2 5 1
133MHz
Min Max 4 7.5 7 1.2 5.5 -
104MHz
Min 0 2 5 1 9.62 3 2 3 3 Max 4 7.5 8 1.6 7 1 12 4 2 3 3
83MHZ
Min 0 2 6 Max 4 7.5 8 1.8 9 -
Unit Notes
ns ns ns 2 2 1
s
ns ns ns ns ns ns ns ns ns
7.5 2.5 1.5 3 2
3
Note: 1. tAS required if tCSP > 20ns. 2. A refresh opportunity must be provided every tCEM. A refresh opportunity is satisfied by either of the following two conditions: a) clocked CE# HIGH, or b) CE# HIGH for longer than 15ns. 3. The High-Z timings measure a 100mV transition from either VOH or VOL toward VccQ/2.
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
TIMING DIAGRAMS
Figure 23: Initialization Period
Vcc(MIN) Vcc, VccQ = 1.7V tPU Device ready for normal operation
Figure 24: DPD Entry and Exit Timing Parameters
tDPD CE#
tDPDX
tPU
Write RCR[4] = 0
DPD Enabled
DPD EXIT
Device Initialization
Device ready for normal operation
Table 17: Initialization and DPD Timing Parameters Symbol
tDPD tDPDX tPU
Min
150 10
Max
Unit s s s
150
35
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 25: Asynchronous READ
tRC
VIH
A[20:0]
VIL VIH
Valid Address
tAA
ADV#
VIL VIH
tCO
tHZ
CE#
VIL VIH
tBA
tBHZ
LB#/UB#
VIL VIH
tOE
tOHZ
OE#
VIL VIH VIL VOH
WE#
tOLZ tBLZ tLZ High-Z tCEW High-Z
DQ[15:0]
VOL VOH
Valid Output
tHZ High-Z
WAIT
VOL
Don't Care
Undefined
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 26: Asynchronous READ Using ADV#
A[20:0]
VIH VIL
Valid Address
tVPH tAVS tAA tAVH tAADV tVP tCVS tCO tBA tBHZ tHZ
ADV#
VIH VIL
CE#
VIH VIL
LB#/UB#
VIH VIL VIH
tOE
tOHZ
OE#
VIL VIH VIL VOH
WE#
tOLZ tBLZ tLZ High-Z tCEW High-Z
DQ[15:0]
VOL VOH
Valid Output
tHZ High-Z
WAIT
VOL
Don't Care
Undefined
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Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 27: PAGE MODE READ
tRC
VIH
A[20:4]
VIL VIH VIL
Valid Address
Valid Address Valid Address Valid Address
A[3:0]
Valid Address
tAA
tPC
ADV#
VIH VIL VIH VIL VIH VIL VIH VIL VIH VIL
tCEM tCO tHZ tBA tBHZ tOE tOHZ
CE#
LB#/UB#
OE#
WE#
tOLZ tBLZ tAPA tOH
Valid Output Valid Output Valid Output Valid Output
VOH
tLZ High-Z tCEW High-Z
DQ[15:0]
VOL VOH
tHZ High-Z
WAIT
VOL
Don't Care
Undefined
38
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 28: Single-Access Burst READ Operation - Variable Latency
tCLK
VIH
tKP
tKP
CLK
VIL
tKHKL tSP tHD
VIH
A[20:0]
VIL VIH VIL
Valid Address
tSP tHD tHD tCEM tCSP tABA tHZ
ADV#
CE#
VIH VIL
OE#
VIH VIL VIH
tBOE tSP tHD tOLZ
tOHZ
WE#
VIL VIH
tSP tKHTL
tHD
LB#/UB#
VIL VOH
tCEW High-Z
WAIT
VOL VOH
High-Z tACLK High-Z tKOH High-Z
DQ[15:0]
Valid Output
VOL
READ Burst Identified (WE# = HIGH)
Note: 1. Non-default BCR settings: Latency code two (three clocks); WAIT active LOW; WAIT asserted during delay.
Don't Care
Undefined
39
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 29: 4-Word Burst READ Operation - Variable Latency
tKHKL
VIH
tCLK
tKP
tKP
CLK
VIL VIH
tSP
tHD
A[20:0]
VIL VIH
Valid Address
tSP tHD tCEM tCSP tABA tHD tCBPH tHZ tBOE tSP tHD tOLZ tOHZ
ADV#
VIL VIH
CE#
VIL VIH
OE#
VIL VIH
WE#
VIL VIH
tSP tKHTL
tHD
LB#/UB#
VIL VOH
tCEW High-Z
WAIT
High-Z tACLK tKOH
Valid Output Valid Output Valid Output Valid Output
VOL VOH
DQ[15:0]
VOL
High-Z
High-Z
READ Burst Identified (WE# = HIGH)
Note: 1. Non-default BCR settings: Latency code two (three clocks); WAIT active LOW; WAIT asserted during delay.
Don't Care
Undefined
40
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 30: Single-Access Burst READ Operation - Fixed Latency
tCLK
VIH
tKP
tKP
CLK
VIL VIH
tSP Valid Address tAVH tSP tHD tAADV tCEM tCSP tCO tAA
tKHKL
A[20:0]
VIL
ADV#
VIH VIL
tHD tHZ
CE#
VIH VIL
OE#
VIH VIL VIH VIL VIH VIL VOH
tBOE tSP tHD tOLZ
tOHZ
WE#
tSP tKHTL
tHD
LB#/UB#
tCEW High-Z
WAIT DQ[15:0]
High-Z tACLK tKOH High-Z
VOL VOH VOL
High-Z
Valid Output
READ Burst Identified (WE# = HIGH)
Don't Care
Undefined
Note: 1. Non-default BCR settings: Fixed latency; latency code four (five clocks); WAIT active LOW; WAIT asserted during delay.
41
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 31. 4-Word Burst READ Operation - Fixed Latency
tCLK tKHKL tKP tKP
CLK
VIH VIL
tSP
tHD
A[20:0]
VIH Valid Address VIL
ADV#
VIH VIL
tSP tCSP
tAVH tHD
tAA
tAADV tCEM tCO tBOE tSP tHD tOLZ
tHD
tCBPH tHZ
CE#
VIH VIL
OE#
VIH VIL
tOHZ
WE#
VIH VIL
LB#/UB#
VIH VIL
tSP tKHTL
tHD
WAIT
VOH VOL High-Z
tCEW
High-Z
tACLK
High-Z Valid Output
DQ[15:0]
VOH VOL
tKOH
Valid Output Valid Output Valid Output
READ Burst Identified (WE# = HIGH)
Don't Care
Undefined
Note: 1. Non-default BCR settings: Fixed latency; latency code two (three clocks); WAIT active LOW; WAIT asserted during delay.
42
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 32. READ Burst Suspend
tCLK
VIH Note 2
CLK A[20:0]
VIL VIH VIL
tSP
tHD
Valid Address
Valid Address
ADV#
VIH VIL
tSP
tHD tCEM tCBPH tHz tOHZ tOHZ
CE#
VIH VIL
tCSP
Note 3
OE#
VIH VIL
tSP
tHD
WE#
VIH VIL
LB#/UB#
VIH VIL
tSP
tOLZ
tBOE
tHD
WAIT
VOH VOL High-Z High-Z
tKOH
High-Z Valid Output Valid Output Valid Output Valid Output
tBOE tOLZ
Valid Output Valid Output
DQ[15:0]
VOH VOL
tACLK Don't Care Undefined
Note: 1. Non-default BCR settings for READ burst suspend: Fixed or variable latency; latency code two (three clocks); WAIT active LOW; WAIT asserted during delay. 2. CLK can be stopped LOW or HIGH, but must be static, with no LOW-to-HIGH transitions during burst suspend. 3. OE# can stay LOW during burst suspend. If OE# is LOW, DQ[15:0] will continue to output valid data.
43
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 33. Burst READ at End-of-Row (Wrap Off)
VIH
CLK
VIL VIH
tCLK
A[20:0]
VIL VIH
ADV#
VIL VIH
UB#/LB#
VIL VIH
tHD Note 2
tCSP
CE#
VIL VIH
OE#
VIL VIH
WE# DQ[15:0]
VIL VOH VOL VOH VOL Valid Output Valid Output
End of row
tKHTL
tHZ
tHZ High-Z
WAIT
tKOH Don't Care Undefined
Note: 1. Non-default BCR settings for burst READ at end of row : fixed or variable latency, WAIT active LOW; WAIT asserted during delay. 2. For burst READs, CE# must go HIGH before the second CLK after the WAIT period begins ( befor the second CLK after WAIT asserts with BCR[8]=0, or before the third CLK after WAIT asserts with BCR[8]=1 ).
44
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 34. Burst READ Row boundary crossing
CLK
VIH VIL
tCLK
A[20:0] ADV#
VIH VIL VIH VIL VIH
UB#/LB#
VIL VIH VIL
CE#
OE#
VIH VIL VIH VIL
WE#
tSP
VOH
tHD
End of row
Valid output Valid output Valid out
DQ[15:0]
Valid output VOL VOH
tKTHL Note 2 tKOH
tKTHL
WAIT V OL
tKOH
Don't Care Note: 1. Non-default BCR settings for burst READ at end of row : fixed or variable latency, WAIT active LOW, WAIT asserted during delay. (shown as solid line) 2. WAIT will be assert for LC or LC + 1 cycles for variables latency, or LC cycles for fixed latency.
45
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 35. CE#-Controlled Asynchronous WRITE
tWC
A[20:0]
VIH VIL Valid Address
tAS
tAW tWR tCW tCPH
ADV#
VIH VIL VIH VIL
CE#
LB#/UB#
VIH VIL
tBW
OE#
VIH VIL
tWPH
tWP
WE# DQ[15:0] IN DQ[15:0] OUT WAIT
VIH VIL VIH
tDW
High-Z
Valid Input
tDH
VIL VOH VOL VOH VOL
tLZ
tWHZ
tCEW
High-Z
tHZ
High-Z
Don't Care
46
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 36. LB#/UB#-Controlled Asynchronous WRITE
tWC
A[20:0]
VIH Valid Address VIL
tAW tAS tCW
tWR
ADV#
VIH VIL
CE#
VIH VIL
LB#/UB#
VIH VIL
tBW
OE#
VIH VIL
tWPH
tWP
WE# DQ[15:0] IN DQ[15:0] OUT WAIT
VIH VIL VIH
tDW
High-Z
Valid Input
tDH
VIL VOH VOL VOH VOL
tLZ
tWHZ
tCEW
High-Z
tHZ
High-Z
Don't Care
47
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 37. WE#-Controlled Asynchronous WRITE
tWC
A[20:0]
VIH Valid Address VIL
tAW
tWR
ADV#
VIH VIL
CE#
VIH VIL
tCW
LB#/UB#
VIH VIL VIH VIL
tBW
tAS tWPH tWP
OE#
WE# DQ[15:0] IN DQ[15:0] OUT WAIT
VIH VIL VIH VIL VOH VOL VOH VOL
tDW
High-Z
Valid Input
tDH
tLZ
tWHZ tOW tHZ
High-Z
tCEW
High-Z
Don't Care
48
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 38. Asynchronous WRITE Using ADV#
A[20:0]
VIH Valid Address VIL
tAVS tVPH tVP tAS tAS tCVS
tAVH tVS tAW tCW
ADV#
VIH VIL VIH
CE#
VIL VIH VIL VIH
tBW
LB#/UB#
OE# WE# DQ[15:0] IN DQ[15:0] OUT WAIT
VIL VIH VIL VIH
tWP
tWPH
tDW
High-Z
Valid Input
tDH
VIL VOH VOL VOH VOL
tLZ
tWHZ tOW tHZ
High-Z
tCEW
High-Z
Don't Care
49
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 39. Burst WRITE Operation - Variable Latency Mode
tCLK tKHKL tKP tKP
CLK
VIH VIL
tSP
tHD
A[20:0]
VIH Valid Address VIL
tAS3 tSP tAS
3
ADV#
VIH VIL
tHD tHD tCEM tCBPH
CE#
VIH VIL
tCSP
OE#
VIH VIL
tSP
tHD
WE#
VIH VIL
tSP
LB#/UB#
VIH VIL VOH VOL ViH D1 ViL
tHD tHZ
High-Z
tCEW
High-Z
Note 2
tKHTL
WAIT
tSP
tHD
D2 D3 D0
DQ[15:0]
WRITE Burst Identified (WE# = Low)
Don't Care
Note: 1. Non-default BCR settings for burst WRITE operation in variable latency mode: Latency code two (three clocks); WAIT active LOW; WAIT asserted during delay; burst length four; burst wrap enabled. 2. WAIT asserts for LC cycles for both fixed and variable latency. LC = Latency Code (BCR[13:11]). 3. tAS required if tCSP > 20ns.
50
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 40. Burst WRITE Operation - Fixed Latency Mode
tCLK tKHKL tKP tKP
CLK
VIH VIL
tSP
Valid Address
A[20:0]
VIH VIL
tAS3 tSP tAS3 tCSP tHD
tAVH
ADV#
VIH VIL
tHD tCEM
tCBPH
CE#
VIH VIL
OE#
VIH VIL
tSP
tHD
WE#
VIH VIL
tSP
LB#/UB# WAIT
VIH VIL VOH VOL
tHD tHZ
High-Z
tCEW
High-Z
Note 2
tKHTL
tSP
D1
tHD
D2 D3 D0
DQ[15:0]
VIH VIL
WRITE Burst Identified (WE# = Low)
Don't Care
Note: 1. Non-default BCR settings for burst WRITE operation in fixed latency mode: Fixed latency; latency code two (three clocks); WAIT active LOW; WAIT asserted during delay; burst length four; burst wrap enabled. 2. WAIT asserts for LC cycles for both fixed and variable latency. LC = Latency Code (BCR[13:11]). 3. tAS required if tCSP > 20ns.
51
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 41. Burst WRITE at End-of-Row (Wrap Off)
VIH
CLK
VIL VIH
tCLK
A[20:0]
VIL VIH
ADV#
VIL VIH
UB#/LB#
VIL VIH
tHD Note 2
tCSP
CE#
VIL VIH
OE#
VIL VIH
WE#
VIL VIH
tSP
tHD
Valid Intput
DQ[15:0]
VIL VOH
Valid Intput
End of row tKOH tKHTL
tHZ
tHZ High-Z
WAIT
VOL
Don't Care
Note: 1. Non-default BCR settings for burst WRITE at end of row: fixed or variable latency, WAIT active LOW, WAIT asserted during delay. (shown as solid line) 2. For burst WRITEs, CE# must go HIGH before the second CLK after the WAIT period begins(befor the second CLK after WAIT asserts with BCR[8]=0, or before the third CLK after WAIT asserts with BCR[8]=1).
52
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 42. Burst WRITE Row boundary crossing
CLK
VIH VIL VIH
tCLK
A[20:0]
VIL
VIH
ADV#
VIL VIH
UB#/LB# CE# OE#
VIL VIH VIL VIH VIL
WE#
VIH VIL VIH
tSP
tHD
Valid input
End of row
Valid input Valid output Valid output
DQ[15:0] WAIT
VIL VOH VOL
Valid input
tKTHL tKOH Note 2
tKTHL
tKOH
Don't Care
Note: 1. Non-default BCR settings for burst WRITE at end of row : Fixed or variable latency, WAIT active LOW, WAIT asserted during delay. (shown as solid line) 2. WAIT will be assert for LC or LC + 1 cycles for variables latency, or LC cycles for fixed latency.
53
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 43. Burst WRITE Followed by Burst READ
tCLK
CLK
VIH VIL
tSP tHD
Valid Address
tSP tHD
Valid Address
A[20:0]
VIH VIL
ADV#
VIH VIL
tSP tHD tHD tCBPH
tSP tHD
tCSP
CE#
VIH VIL Note 2
tCSP
tOHZ
OE#
VIH VIL
tSP tHD
tSP tHD
WE#
VIH VIL
LB#/UB# WAIT DQ[15:0] IN/OUT
VIH VIL VOH VOL VIH
tSP
tHD
tBOE
High-Z High-Z
tSP tHD
VOH
tACLK
D1 D2 D3 VOL
tKOH
Valid Output Valid Output Valid Output Valid Output
High-Z
VIL
D0
High-Z
Don't Care
Undefined
Note: 1. Non-default BCR settings for burst WRITE followed by burst READ: Fixed or variable latency; latency code two (three clocks); WAIT active LOW; WAIT asserted during delay. 2. A refresh opportunity must be provided every tCEM. A refresh opportunity is satisfied by either of the following two conditions: a) clocked CE# HIGH, or b) CE# HIGH for longer than 15ns. CE# can stay LOW between burst READ and burst WRITE operations, but CE# must not remain LOW longer than tCEM. See burst interrupt diagrams for cases where CE# stays LOW between bursts.
54
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 44. Burst READ Interrupted by Burst READ or WRITE READ Burst interrupted with new READ or WRITE. See Note 2.
tCLK
CLK
VIH VIL
tSP tHD
Valid Address
tSP tHD
Valid Address
A[20:0]
VIH VIL
ADV#
VIH VIL
tSP tHD tCSP
tSP tHD
CE#
VIH VIL
tCEM (Note 3) tSP tHD
tHD
tSP tHD
WE#
VIH VIL
tKHTL
High-Z
WAIT OE# LB#/UB#
VOH VOL VIH
tBOE
tCEW
tOHZ
tBOE
tOHZ
2nd Cycle READ VIL VIH
2nd Cycle READ VIL
tACLK
Valid Output
tKOH
High-Z
Valid Output Valid Output Valid Output Valid Output
DQ[15:0] OUT
VOH
2nd Cycle READ VOL
tACLK
OE# VIH
2nd Cycle Write VIL VIH
LB#/UB#
2nd Cycle Write V IL
tSP tHD
High-Z
DQ[15:0] IN
VIH
2nd Cycle Write VIL
D0
D1
D2
D3
Don't Care
Undefined
Note: 1. Non-default BCR settings for burst READ interrupted by burst READ or WRITE: Fixed or variable latency code two (three clocks); WAIT active LOW; WAIT asserted during delay. All bursts shown for variable latency; no refresh collision. 2. Burst interrupt shown on first allowable clock (i.e., after the first data received by the controller). 3. CE# can stay LOW between burst operations, but CE# must not remain LOW longer than tCEM.
55
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 45. Burst WRITE Interrupted by Burst WRITE or READ - Variable Latency Mode
tCLK
WRITE Burst interrupted with new WRITE or READ. See Note 2.
CLK
VIH VIL
tSP tHD
Valid Address
tSP tHD
Valid Address
A[20:0]
VIH VIL
ADV#
VIH VIL
tSP tHD tCSP
tSP tHD
CE#
VIH VIL
tCEM (Note 3) tSP tHD
tHD
tSP tHD
WE#
VIH VIL
tKHTL
High-Z High-Z
WAIT
VOH VOL
tCEW
OE# VIH
2nd Cycle WRITE
VIL VIH VIL
tSP tHD
LB#/UB#
2nd Cycle WRITE
tSP tHD
High-Z
tSP tHD D0 tBOE D1 D2 D3 tOHZ
DQ[15:0] IN VIH
2nd Cycle WRITE
VIL
D0
VIH VIL VIH VIL VOH VOL VOH
OE#
2nd Cycle READ
tSP
tHD
LB#/UB#
2nd Cycle READ
tACLK
High-Z
VOL
Valid Output
tKOH
Valid Output Valid Output Valid Output
DQ[15:0] OUT
2nd Cycle READ
Don't Care
Undefined
Note: 1. Non-default BCR settings for burst WRITE interrupted by burst WRITE or READ in variable latency mode: Variable latency; latency code two (three clocks); WAIT active LOW; WAIT asserted during delay. All bursts shown for variable latency; no refresh collision. 2. Burst interrupt shown on first allowable clock (i.e., after first data word written). 3. CE# can stay LOW between burst operations, but CE# must not remain LOW longer than tCEM.
56
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 46. Burst WRITE Interrupted by Burst WRITE or READ - Fixed Latency Mode
tCLK
WRITE Burst interrupted with new WRITE or READ. See Note 2.
CLK
VIH VIL
tSP tHD
Valid Address
tSP tHD
Valid Address
A[20:0]
VIH VIL
ADV#
VIH VIL
tSP tHD tCSP
tAVH
tSP tHD
CE#
VIH VIL
tCEM (Note 3) tSP tHD
tHD
tSP tHD
WE#
VIH VIL
tKHTL
High-Z High-Z
WAIT OE#
2nd Cycle WRITE
VOH VOL VIH VIL VIH VIL VIH
tCEW
tSP tHD
LB#/UB#
2nd Cycle WRITE
tSP tHD
High-Z
tSP tHD D0 tBOE D1 D2 D3 tOHZ
DQ[15:0] IN
2nd Cycle WRITE
VIL
D0
VIH VIL VIH VIL VOH VOL VOH
OE#
2nd Cycle READ
tSP
tHD
LB#/UB#
2nd Cycle READ
tACLK
High-Z
VOL
Valid Output
tKOH
Valid Output Valid Output Valid Output
DQ[15:0] OUT
2nd Cycle READ
Don't Care
Undefined
Note: 1. Non-default BCR settings for burst WRITE interrupted by burst WRITE or READ in fixed latency mode: Fixed latency; latency code two (three clocks); WAIT active LOW; WAIT asserted during delay. 2. Burst interrupt shown on first allowable clock (i.e., after first data word written). 3. CE# can stay LOW between burst operations, but CE# must not remain LOW longer than tCEM.
57
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 47. Asynchronous WRITE Followed by Burst READ
tCLK
CLK A[20:0]
VIH VIL VIH Valid Address VIL Valid Address Valid Address
tWC
tWC
tSP
tHD
tAVS tVP tVPH tCVS tCW
tAVH
tAW
tWR
ADV#
VIH VIL VIH
tSP
tHD
tVS
tCBPH
Note 2
tCSP
CE#
VIL VIH VIL VIH
tAS
tOHZ
OE#
tAS
tWP
tWC tWPH tBW
tSP tHD
WE#
VIL VIH VIL VOH
tSP tBOE
tHD
LB#/UB#
tCEW tDH
High-Z
WAIT DQ[15:0] IN/OUT
High-Z
VOL VIH
tDW
VOH
tACLK
High-Z
VOL
Valid Output
tKOH
Valid Output Valid Output Valid Output
Data
Data
VIL
Don't Care
Undefined
Note: 1. Non-default BCR settings for asynchronous WRITE followed by burst READ: Fixed or variable latency; latency code two (three clocks); WAIT active LOW; WAIT asserted during delay. 2. When transitioning between asynchronous and variable-latency burst operations, CE# must go HIGH. CE# can stay LOW when transitioning to fixed-latency burst READs. A refresh opportunity must be provided every tCEM. A refresh opportunity is satisfied by either of the following two conditions: a) clocked CE# HIGH, or b) CE# HIGH for longer than 15ns.
58
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 48. Asynchronous WRITE (ADV# LOW) Followed By Burst READ
tCLK
CLK A[20:0]
VIH VIL VIH Valid Address VIL Valid Address Valid Address
tWC
tWC
tSP
tHD
tAW
tWR
ADV#
VIH VIL VIH
tSP tCBPH tCSP
tHD
tCW
CE#
VIL VIH VIL VIH VIL VIH
Note 2
tOHZ
OE#
tWP
tWC tWPH tBW
tSP tHD
WE#
tSP tCEW tBOE
tHD
LB#/UB#
VIL VOH
WAIT DQ[15:0] IN/OUT
VOL VIH VIL
High-Z
tDH
High-Z
tDW
Data
VOH VOL
tACLK
High-Z
tKOH
Valid Output Valid Output Valid Output Valid Output
Data
Don't Care
Undefined
Note: 1. Non-default BCR settings for asynchronous WRITE, with ADV# LOW, followed by burst READ: Fixed or variable latency; latency code two (three clocks); WAIT active LOW; WAIT asserted during delay. 2. When transitioning between asynchronous and variable-latency burst operations, CE# must go HIGH. CE# can stay LOW when transitioning to fixed-latency burst READs. A refresh opportunity must be provided every tCEM. A refresh opportunity is satisfied by either of the following two conditions: a) clocked CE# HIGH, or b) CE# HIGH for longer than 15ns.
59
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 49. Burst READ Followed by Asynchronous WRITE (WE#-Controlled)
tCLK
CLK
VIH VIL
tSP
tHD
A[20:0]
VIH Valid Address VIL
tWC
Valid Address
ADV#
VIH VIL
tSP
tHD tHD tHZ tBOE tOHZ tCBPH
Note 2
tAW
tWR
CE#
VIH VIL
tCSP
tCW
OE#
VIH VIL
tSP
tHD
tOLZ
tAS
tWP
tWPH
WE#
VIH VIL
LB#/UB#
VIH VIL VOH VOL VOH
tSP tKHTL
tBW
tCEW
High-Z
tCEW
High-Z
tHZ
WAIT
tACLK
High-Z
tKOH
tDW
tDH
DQ[15:0]
Valid Output
Valid Input
VOL
READ Burst Identified (WE# = HIGH)
Don't Care
Undefined
Note: 1. Non-default BCR settings for burst READ followed by asynchronous WE#-controlled WRITE: Fixed or variable latency; latency code two (three clocks); WAIT active LOW; WAIT asserted during delay. 2. When transitioning between asynchronous and variable-latency burst operations, CE# must go HIGH. CE# can stay LOW when transitioning from fixed-latency burst READs; asynchronous operation begins at the falling edge of ADV#. A refresh opportunity must be provided every tCEM. A refresh opportunity is satisfied by either of the following two conditions: a) clocked CE# HIGH, or b) CE# HIGH for longer than 15ns.
60
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 50. Burst READ Followed by Asynchronous WRITE Using ADV#
tCLK
CLK
VIH VIL VIH Valid Address VIL Valid Address
tSP
tHD
A[20:0]
tAVS tSP tHD tVP
tAVH
tVS
ADV#
VIH VIL
tAW tCSP tHD tHZ tBOE tSP tHD tOLZ tOHZ tCBPH
Note 2
tAS
CE#
VIH VIL VIH VIL
tCW
OE#
tAS
tWP
tWPH
WE#
VIH VIL VIH VIL
tSP
tHD
tBW
LB#/UB#
WAIT
VOH VOL
tCEW
High-Z
tKHTL
High-Z
tCEW
tHZ
DQ[15:0]
VOH VOL
tACLK
High-Z
tKOH
tDW
Valid Input
tDH
Valid Output
READ Burst Identified (WE# = HIGH)
Don't Care
Undefined
Note: 1. Non-default BCR settings for burst READ followed by asynchronous WRITE using ADV#: Fixed or variable latency; latency code two (three clocks); WAIT active LOW; WAIT asserted during delay. 2. When transitioning between asynchronous and variable-latency burst operations, CE# must go HIGH. CE# can stay LOW when transitioning from fixed-latency burst READs; asynchronous operation begins at the falling edge of ADV#. A refresh opportunity must be provided every tCEM. A refresh opportunity is satisfied by either of the following two conditions: a) clocked CE# HIGH, or b) CE# HIGH for longer than 15ns.
61
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 51. Asynchronous WRITE Followed by Asynchronous READ - ADV# LOW
A[20:0]
VIH Valid Address VIL Valid Address Valid Address
tAW
tWR
tAA
ADV#
VIH VIL
CE#
VIH VIL
tCW
tCPH
Note 1
tLZ
tHZ
OE#
VIH VIL
tOE tAS tWP tWC tWPH tBW tHZ tBLZ
tOHZ
WE#
VIH VIL
tBHZ
LB#/UB# WAIT DQ[15:0] IN/OUT
VIH VIL VOH VOL VIH VIL
tHZ
tDH
High-Z
Data
tDW
VOH
Data
tOLZ
High-Z
VOL
Valid Output
Don't Care
Undefined
Note: 1. When configured for synchronous mode (BCR[15] = 0), CE# must remain HIGH for at least 5ns (tCPH) to schedule the appropriate refresh interval. Otherwise, tCPH is only required after CE#-controlled WRITEs.
62
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
Figure 52. Asynchronous WRITE Followed by Asynchronous READ
A[20:0]
VIH Valid Address VIL VIH Valid Address Valid Address
tAVS
tAVH
tAW
tWR
tAA
ADV#
VIL VIH VIL
tVP
tVS
tCPH
tLZ
tHZ
CE#
tCW
tAS
Note 1
OE#
VIH VIL VIH
tOE tOLZ
tOHZ
tAS tWP
tWC tWPH
WE#
VIL VIH VIL VOH
tCVS
tBW
tBLZ
tBHZ
LB#/UB#
WAIT DQ[15:0] IN/OUT
VOL VIH
tDH
High-Z
tDW
VOH
Data
Data
VOL
VIL
High-Z
Valid Output
Don't Care
Undefined
Note: 1. When configured for synchronous mode (BCR[15] = 0), CE# must remain HIGH for at least 5ns (tCPH) to schedule the appropriate refresh interval. Otherwise, tCPH is only required after CE#-controlled WRITEs.
63
Preliminary
EMC326SP16AJ
2Mx16 CellularRAM
MEMORY FUNCTION GUIDE
EM X XX X X X XX X X X - XX XX
1. EMLSI Memory 2. Device Type 3. Density 4. Function 5. Technology 6. Operating Voltage
1. Memory Component 2. Device Type 6 ---------------------- Low Power SRAM 7 ---------------------- STRAM C ---------------------- CellularRAM 3. Density 4 ----------------------- 4M 8 ----------------------- 8M 16 --------------------- 16M 32 --------------------- 32M 64 --------------------- 64M 28 --------------------- 128M 4. Function 2 ----Multiplexed async. 3-----Demultiplexed async. with page mode 4-----Demultiplexed async. with direct DPD 5-----Multiplexed sync. 6-----Optional mux/demuxed sync. 5. Technology S ----------------------- Single Transistor & Trench Cell 6. Operating Voltage V ----------------------- 3.3V U ----------------------- 3.0V S ----------------------- 2.5V R ----------------------- 2.0V P ----------------------- 1.8V L ----------------------- 1.5V 7. Organization 8 ---------------------- x8 bit 16 ---------------------- x16 bit 32 ---------------------- x32 bit
12. Power 11. Speed 10. PKG 9. Option 8. Version 7. Organization
8. Version Blank ----------------- Mother die A ----------------------- 2'nd generation B ----------------------- 3'rd generation C ----------------------- 4'th generation D ----------------------- 5'th generation 9. Option Blank ---- No optional mode H ----------- Demultiplexed with DPD J ------------ Demultiplexed with DPD & RBC K ------------ Multiplexed with RBC L ------------ Multiplexed with DPD & RBC 10. Package Blank ---------------------- Wafer S ---------------------- 32 sTSOP1 T ---------------------- 32 TSOP1 U ---------------------- 44 TSOP2 P ---------------------- 48 FPBGA Z ---------------------- 52 FPBGA Y ---------------------- 54 FPBGA V ---------------------- 90 FPBGA 11. Speed (@async.) 45 ---------------------- 45ns 55 ---------------------- 55ns 70 ---------------------- 70ns 85 ---------------------- 85ns 90 ---------------------- 90ns 10 --------------------- 100ns 12 --------------------- 120ns 12. Power LL ---------------------- Low Low Power LF ---------------------- Low Low Power (Pb-Free&Green) L ---------------------- Low Power 64


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