View RT922807_4120935.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

RT9228
Advanced PWM and Dual Fixed Linear Power Controller
General Description
The RT9228 is a 3-in-one power controller optimized for high-performance microprocessor and computer applications. The IC integrates a synchronous buck PWM controller, a linear regulator, and a linear controller as well as monitoring and protection functions into a 24-pin SOP package. The PWM controller regulates the microprocessor core voltage. The linear regulator provides power for the clock driver circuit and the linear controller regulates power for the GTL bus. The RT9228 features an Intel-compatible, TTL 5-bit programmable DAC that adjusts the core voltage from 2.1V to 3.5V in 0.1V increments and from 1.3V to 2.05V in 0.05V steps. The 5-bit DAC has a typical 1% tolerance. The linear regulator uses an internal drive device to provide 2.5V 2.5% output voltage. The linear controller drives an external N-Channel MOSFET or a low cost NPN bipolar transistor to provide 1.5V 2.5%. The RT9228 monitors all the output voltages. A Powergood signal is issued when the core voltage is within 10% of the DAC setting and the other levels are above their under-voltage levels. Additional build-in over-voltage protection for the core output uses the lower MOSFET to prevent output voltage above 115% of the DAC setting. The PWM over-current function monitors the output current using the voltage drop across the upper MOSFET's RDS(ON), which eliminates the need for a current sensing resistor.
Features
3-in-one Regulated Voltages for Microprocessor Core, Clock, and GTL Compatible with HIP6016 Power-good Output Voltage Monitor Switching Section 5-bit DAC Programmable from 1.3V to 3.5V 1% DAC Accuracy Fast Transient Response Full 0% to 100% Duty Cycle Driver Fixed 200kHz Switching Frequency Adaptive Non-Overlapping Gate Driver Over-Current Monitor Uses MOSFET RDS(ON) Over-Voltage Protection Uses Lower MOSFET Linear Section Fixed Linear Regulator Output Voltage MOSFET or NPN Driving Capability Ultra Fast Response Speed Under-Voltage Protection Internal Thermal Shutdown RoHS Compliant and 100% Lead (Pb)-Free
Applications
Full Motherboard Power Regulation for Computer Low-voltage Distributed Power Supplies
Pin Configurations
(TOP VIEW)
VCC VID4 VID3 VID2 VID1 VID0 PGOOD FAULT SS NC FB2 VIN2 2 3 4 5 6 7 8 9 10 11 12 24 23 22 21 20 19 18 17 16 15 14 13 UGATE1 PHASE1 LGATE1 PGND OCSET1 VSEN1 FB1 NC FB3 GATE3 GND VOUT2
Ordering Information
RT9228 Package Type S : SOP-24 Operating Temperature Range P : Pb Free with Commercial Standard G : Green (Halogen Free with Commercial Standard)
Note : RichTek Pb-free and Green products are : RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. 100%matte tin (Sn) plating. DS9228-06 March 2007
SOP-24
www.richtek.com 1
RT9228
Typical Application Circuit
12V F1 15A C1-4 4 x 1000uF L1 1uH
+
5V GND
R1 10
C5-6 2 x 1uF C20 1uF C7
1 VCC 3.3V 12
+
VIN2
OSET1 PGOOD
20 7
1000pF R2 1.21K POWERGOOD R3 10K VOUT1 1.3V to 3.5V
C8 1000uF VOUT3 1.5V Q3 RFD3055
+
15 16
GATE3 FB3 UGATE1 PHASE2 RT9228 VOUT2 LGATE1 FB2 VID0 VID1 VID2 VID3 VID4 SS GND 14 FAULT PGND VSEN1 FB1
24 23 22 21 19 18 8 9
Q1 PHB83N03LT
C9 1000uF VOUT2 2.5V
+
L2 3.5uH
+
13 11
Q2 PHB95N03LT
R4 4.99K
C13-19 7 x 1000uF
C10 270uF
6 5 4 3 2
C11 R5 0.68uF 732K
C12 0.039uF
Function Block Diagram
VSEN1 OCSET1 VCC
FB3 GATE3 VIN2 3.3V + +
0.3V
110% + + 90%
Power-On Reset (POR) + + -
3.3V
PGOOD VCC UGATE1 Over Voltage
VOUT2 FB2
1.26V
115% + + OC2
0.25A FAULT
Soft Start & Fault Logic
OC1
+ -
Inhibit Gate Control Logic VCC Oscillator Lower Drive
PHASE1
VCC 11uA 5V
DACOUT
+ Error Amplifier
TTL D/A Converter (DAC)
PWM Comparator + -
PWM
LGATE1 PGND GND
Compensation
www.richtek.com 2
VID0 VID1 VID2 VID3 VID4
SS
FB1
DS9228-06 March 2007
RT9228
Absolute Maximum Ratings
Supply Voltage ----------------------------------------------------------------------------------------------------- +15V PGOOD, FAULT and GATE Voltage --------------------------------------------------------------------------- GND-0.3V to VCC+0.3V Input, Output or I/O Voltage ------------------------------------------------------------------------------------- GND-0.3V to 7V Ambient Temperature Range ------------------------------------------------------------------------------------ 0C to +70C Junction Temperature Range ------------------------------------------------------------------------------------ 0C to +125C Storage Temperature Range ------------------------------------------------------------------------------------ -65C to +150C Lead Temperature (Soldering, 10 sec.) ----------------------------------------------------------------------- 260C Package Thermal Resistance SOP-24, JA -------------------------------------------------------------------------------------------------------- 75C/W
Recommended Operating Conditions
Supply Voltage ----------------------------------------------------------------------------------------------------- +12V 10% Ambient Temperature Range ------------------------------------------------------------------------------------ 0C to 70C Junction Temperature Range ------------------------------------------------------------------------------------ 0C to 125C CAUTION: Stresses beyond the ratings specified in "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
Electrical Characteristics
(VCC = 12V, PGND = 0V, TA = 25C, unless otherwise specified)
Parameter VCC Supply Current Nominal Supply Current Power-On Reset VCC Rising Threshold VCC Falling Threshold Rising VIN2 Under-voltage Threshold VIN2 Under-voltage Hysteresis Rising VOCSET1 Threshold Oscillator Free Running Frequency Ramp Amplitude
Symbol
Test Conditions
Min
Typ
Max
Units
ICC
UGATE1, GATE3, LGATE1, and VOUT2 Open
--
10
--
mA
VOCSET1 = 4.5V VOCSET1 = 4.5V
7.5 7 ----
--2.8 0.5 1.25
9.5 9 ----
V V V V V
180 VOSC --
200 1.9
225 --
kHz VP-P
To be continued
DS9228-06 March 2007
www.richtek.com 3
RT9228
Parameter Reference and DAC DAC (VID0-VID4) Input Low Voltage DAC (VID0-VID4) Input High Voltage DACOUT Voltage Accuracy DACOUT Voltage Accuracy Reference Voltage (Pin FB2 and FB3) Linear Regulator Regulation Under-voltage Level Under-voltage Hysteresis Over-current Protection Over-current Protection During Start-up Linear Controller Regulation Under-voltage Level Under-voltage Hysteresis Output Drive Current PWM Controller Error Amplifier DC Gain PWM Controller Gate Driver UGATE Source UGATE Sink LGATE Source LGATE Sink Protection VOUT1 Over-voltage Trip FAULT Souring Current OCSET1 Current Source Soft-start Current Power Good VOUT1 Upper Threshold VOUT1 Under Voltage VOUT1 Hysteresis (VSEN1/DACOUT) PGOOD Voltage Low
www.richtek.com 4
Symbol
Test Conditions
Min
Typ
Max
Units
-2.0 DACOUT = 2.05 ~ 3.50V DACOUT = 1.30 ~ 2.00V VREF 10mA < IVOUT2 < 150mA FB2 Rising -1 -1% 1.240
----1.265
0.8 -1 20mV 1.290
V V % V
-2.5 ---
-75 100 230 700
2.5 87 ----
% % mV mA mA
IOVP
180 --
VSEN3 = GATE3 0 < IGATE3 < 20mA FB3 Rising VIN2 - VOUT3 > 1.5V
-2.5 --20
-75 100 40
2.5 87 ---
% % mV mA
--
65
--
dB
RUGATE1
VCC = 12V VCC - VUGATE1 = 1V VCC = 12V VLGATE1 = 2V
-----
3 3 1 2
7 7 -6
A
RUGATE1 VUGATE1 = 1V ILGATE1
RLGATE1 VLGATE1 = 1V
VSEN1 Rising IOVP IOCSET ISS VFAULT = 8V VOCSET1 = 4.5V VSS = 1V
112 10 170 --
115 14 200 11
120 -230 --
% mA A A
VSEN1 Rising VSEN1 Rising Upper/Lower Threshold VPGOOD IPGOOD = -4mA
108 89 ---
--2 --
112 95 -0.5
% % % V
DS9228-06 March 2007
RT9228
Functional Pin Description
VCC (Pin 1) Provide a 12V bias supply for the IC to this pin. This pin also provides the gate bias charge for all the MOSFETs controlled by the IC. VID0, VID1, VID2, VID3, VID4 (Pin 6, 5, 4, 3, and 2) VIDO-4 are the input pins to the 5-bit DAC. The states of these five pins program the internal voltage reference, DACOUT. The level of DACOUT sets the core converter output voltage. It also sets the core PGOOD and OVP thresholds. Table 1 specifies the DACOUT voltage of 32 combinations of VID levels. PGOOD (Pin 7) PGOOD is an open collector output used to indicate the status of the output voltage. This pin is pulled low when the core output is not within 10% of the DACOUT reference voltage and the other outputs are below their under-voltage thresholds. The PGOOD output is open for '11111' VID codes that inhibit operation. See table 1. FAULT (Pin 8) This pin is low during normal operation, but it is pulled to about 8V (VCC = 12V) in the event of an over-voltage or over-current condition. SS (Pin 9) Connect a capacitor from this pin to ground. This capacitor, along with an internal 11A (VSS >1V) current source, sets the soft-start interval of the converter. FB2 (Pin 11) Connect this pin to VOUT2 to set the linear regulator output voltage. VIN2 (Pin 12) This pin supplies power to the internal regulator. Connect this pin to a suitable 3.3V source. VOUT2 (Pin 13) Output of the linear regulator. Supplies current up to 230mA. GND (Pin 14) Signal ground for the IC. All voltage levels are measured with respect to this pin. GATE3 (Pin 15) Connect this pin to the gate of an external MOSFET or the base of an NPN. This pin provides the drive for the linear controller's pass transistor. FB3 (Pin 16) Connect this pin to VOUT3 to set the linear controller output voltage. FB1 (Pin 18) The FB1 pin is the inverting input of the error amplifier. VSEN1 (Pin 19) This pin is connected to the PWM converter's output voltage. The PGOOD and OVP comparator circuits use this signal to report output voltage status and for over voltage protection. OCSET1 (Pin 20) Connect a resistor (ROCSET1) from this pin to the drain of the upper MOSFET. ROCSET1, an internal 200A current source (IOCSET1), and the upper MOSFET on-resistance (RDS(ON)) set the PWM converter over-current (OC) trip point according to the following equation : Additionally, this pin is used to monitor the 3.3V supply. If, following a startup cycle, the voltage drops below 2.55V (typically), the chip shuts down. A new soft-start cycle is initiated upon return of the 3.3V supply above the undervoltage threshold.
IPEAK
=
IOCSET1 x ROCSET1 RDS (ON)
An over-current trip cycles the soft-start function. Sustaining an over-current for 2 soft-start intervals shuts down the controller.
DS9228-06 March 2007
www.richtek.com 5
RT9228
PGND (Pin 21) This is the power ground of UGATE1 and LGATE1. Tie the PWM converter's lower MOSFET source to this pin. LGATE1 (Pin 22) Connect LGATE1 to the PWM converter's lower MOSFET gate. This pin provides the gate drive for the lower MOSFET. An over-current trip cycles the soft-start function. Sustaining an over-current for 2 soft-start intervals shuts down the controller. PHASE1 (Pin 23) Connect the PHASE1 pin to the PWM converter's upper MOSFET source. This pin is used to monitor the voltage drop across the upper MOSFET for over-current protection. UGATE1 (Pin 24) Connect UGATE pin to the PWM converter's upper MOSFET gate. This pin provides the gate drive for the upper MOSFET.
www.richtek.com 6
DS9228-06 March 2007
RT9228
Table 1. VOUT1 Voltage Program
Pin Name VID4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 VID3 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 VID2 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 VID1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 VID0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 Normal OUT1 Voltage DACOUT 1.30 1.35 1.40 1.45 1.50 1.55 1.60 1.65 1.70 1.75 1.80 1.85 1.90 1.95 2.00 2.05 INHIBIT 2.10 2.20 2.30 2.40 2.50 2.60 2.70 2.80 2.90 3.00 3.10 3.30 3.30 3.40 3.50
DS9228-06 March 2007
www.richtek.com 7
RT9228
Outline Dimension
A
H M
J
B
F
C I D
Symbol A B C D F H I J M
Dimensions In Millimeters Min 15.189 7.391 2.362 0.330 1.194 0.229 0.102 10.008 0.381 Max 15.596 7.595 2.642 0.508 1.346 0.330 0.305 10.643 1.270
Dimensions In Inches Min 0.598 0.291 0.093 0.013 0.047 0.009 0.004 0.394 0.015 Max 0.614 0.299 0.104 0.020 0.053 0.013 0.012 0.419 0.050
24-Lead SOP Plastic Package
Richtek Technology Corporation
Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611
Richtek Technology Corporation
Taipei Office (Marketing) 8F, No. 137, Lane 235, Paochiao Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)89191466 Fax: (8862)89191465 Email: marketing@richtek.com
www.richtek.com 8
DS9228-06 March 2007

▲Up To Search▲

Price & Availability of RT922807

	To Download RT922807 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .