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October 2006 rev 1.6 General Purpose EMI Reduction IC
Features
* * * * * * * * * * * * Provides up to 15dB of EMI suppression FCC approved method of EMI attenuation Generates a 1X, 2X, and 4X low EMI spread spectrum clock of the input frequency Input frequency range from 3 to 78MHz External loop filter for spread % adjustment Spreading ranges from 0.25% to 5.0% Ultra low cycle-to-cycle jitter Zero-cycle slip 3.3V operating voltage range Ultra-low power CMOS design P278xA is available in 8 pin SOIC and TSSOP Packages Available for industrial and automotive temperature ranges.
P2781/82/84
reduces electromagnetic interference (EMI) at the clock source, which provides system wide reduction of EMI of all clock dependent signals. The P278xA allows significant system cost savings by reducing the number of circuit board layers and shielding that are traditionally required to pass EMI regulations. The P278xA uses the most efficient and optimized modulation profile approved by the FCC. The P278xA modulates the output of a single PLL in order to "spread" the bandwidth of a synthesized clock and, more importantly, decreases the peak amplitudes of its harmonics. This result in significantly lower system EMI compared to the typical narrow band signal produced by oscillators and most frequency generators. Lowering EMI by increasing a signal's bandwidth is called spread spectrum clock generation.
Product Description
The P278xA is a versatile spread spectrum frequency modulator designed specifically for digital camera and other digital video and imaging applications. The P278xA
Applications
The P278xA is targeted towards MFP, xDSL, fax modem, set-top box, USB controller, DSC, and embedded systems.
Block Diagram
FS0 FS1 LF VDD
PLL Modulation XIN /CLKIN XOUT Crystal Oscillator Frequency Divider Feedback Divider Phase Detector VCO
Output Divider
ModOUT
VSS
PulseCore Semiconductor Corporation 1715 S. Bascom Ave Suite 200, Campbell, CA 95008 * Tel: 408-879-9077 * Fax: 408-879-9018 www.pulsecoresemi.com
Notice: The information in this document is subject to change without notice.
October 2006 rev 1.6
Pin Configuration
XIN / CLKIN XOUT FS1 LF 1 2 8 7 VDD FS0 ModOUT VSS
P2781/82/84
P278xA
3 4 6 5
Standard pin Configuration offered in both 8 pin SOIC and TSSOP Packages
Pin Description (P278xA) Pin#
1 2 3 4 5 6 7 8
Pin Name
XIN/CLKIN XOUT FS1 LF VSS ModOUT FS0 VDD
Type
I O I I I O I P
Description
Connect to crystal or clock input. This pin has dual functions. It can be connected either to an external crystal or an external reference clock. Crystal connection. If using an external reference, this pin must be left unconnected. Digital logic input used to select input frequency range (see the Input Frequency Selection Table). This pin has an internal pull-up resistor. External Loop Filter for the PLL. By changing the value of the CRC circuit, the percentage spread can be adjusted accordingly. See the Loop Filter Selection Table for detail value. Ground Connection. Connect to system ground. Spread Spectrum Clock Output. Digital logic input used to select input frequency range (see the Input Frequency Selection Table). This pin has an internal pull-up resistor. Connect to +3.3 V
Input Frequency Selection Table FS1
0 0 1 1
FS0
0 1 0 1
Input (MHz)
3 to 9 10 to 19 20 to 38 39 to 78
Output Frequency Scaling (MHz) P2781A
3 to 9 10 to 19 20 to 38 39 to 78
P2782A
6 to 18 20 to 38 40 to 76 78 to 156
P2784A
12 to 36 40 to 76 80 to 152 156 to 312
Modulation Rate (KHz)
Fin / 128 Fin / 256 Fin / 512 Fin / 1024
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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October 2006 rev 1.6
Loop Filter Selection Table VDD 3.3V
P2781/82/84
Contact PulseCore for loop values that are not listed in the table and for component selection values for industrial and automotive temperatures.
BW = 0.50% Input MHz 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21-22 23-24 25-26 27-28 29-30 31-32 33-34 35-36 37-38 39-42 43-46 47-50 51-54 55-58 59-62 63-66 67-70 71-74 75-78 FS1 FS0 0 0 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 1 1 1 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 C1 (pF) 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 C2 (pF) 330,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000
1
BW = 0.75% C1 (pF) 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 C2 (pF) 330,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000 100,000
1
BW = 1.00% C1 (pF) 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 C2 (pF)
1
BW = 1.25% C1 (pF) 560 560 560 680 330 680 270 560 560 680 470 330 330 680 390 270 270 560 560 680 470 330 330 680 390 270 270 560 560 680 470 330 330 680 390 270 270 C2 (pF) 100,000 100,000 100,000 6,800 3,300 6,800 2,700 100,000 100,000 6,800 4,700 3,300 3,300 6,800 3,900 2,700 2,700 100,000 100,000 6,800 4,700 3,300 3,300 6,800 3,900 2,700 2,700 100,000 100,000 6,800 4,700 3,300 3,300 6,800 3,900 2,700 2,700
1
R1 (ohm) 220 270 390 510 620 820 1,000 330 390 510 560 620 750 820 910 1,000 1,200 330 390 510 560 620 750 820 910 1,000 1,200 330 390 510 560 620 750 820 910 1,000 1,200
R1 (ohm) 300 390 560 750 1,000 1,200 1,500 510 560 750 820 1,000 1,100 1,200 1,300 1,500 1,600 560 620 750 820 1,000 1,100 1,200 1,300 1,500 1,600 560 620 750 820 1,000 1,100 1,200 1,300 1,600 1,800
R1 (ohm)
R1 (ohm) 510 680 910 1,200 1,200 2,200 2,200 910 1,100 1,200 1,200 1,200 1,500 2,200 2,200 2,200 2,700 910 1,100 1,200 1,200 1,200 1,500 2,200 2,200 2,200 2,700 910 1,100 1,200 1,200 1,200 1,500 2,200 2,200 2,200 2,700
100,000 390 100,000 560 100,000 750 10,000 1,000 5,600 1,200 12,000 2,200 5,600 2,200 100,000 750 100,000 866(1%) 10,000 1,000 12,000 1,200 5,600 1,200 3,900 1,200 12,000 2,200 10,000 2,200 5,600 2,200 3,300 2,200 100,000 750 100,000 866 (1%) 10,000 1,000 12,000 1,200 6,800 1,200 3,900 1,200 12,000 2,200 10,000 2,200 5,600 2,200 3,300 2,200 100,000 750 100,000 866 (1%) 10,000 1,000 12,000 1,200 6,800 1,200 3,900 1,200 12,000 2,200 8,200 2,200 5,600 2,200 3,300 2,200
1 The BW value is representative of typical conditions
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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October 2006 rev 1.6
Spread Spectrum Selection
P2781/82/84
The P278xA performs Zero Cycle Slip when set at low percentage spreading. This allows no occurrence of system timing error. The optimal setting should minimize system EMI to the fullest without affecting system performance. The spreading is described as a percentage deviation of the center frequency. (Note: the center frequency is the frequency of the external reference input on CLKIN, Pin 1.) The P2781A is designed for PC peripheral, networking, notebook PC, and LCD monitor applications. It is optimized for operation between 3 to 78MHz range. In the following application schematic example, the P2781A spread percentage selection is determined by the external LF value specified in the Loop Filter Selection Table. The Input Frequency Selection Table specifies the input frequency range. The external LF allows the user to fine tune the spread percentage to optimize the EMI reduction benefits of the spread spectrum.
+3.3V 16 MHz 1 XIN/CLKIN VDD 8 2 XOUT 3 FS1 R1 C1 4 LF 0 Ohm FS0 7 ModOUT 6 VSS 5 P278xA 2.2 K 0.1F Modulated 16MHz Clock To target Chip
C2
Note: Both logic input pins FS1 and FS0 have to be connected to either VDD or VSS. Do not leave them floating.
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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October 2006 rev 1.6
Absolute Maximum Ratings Symbol
VDD, VIN TSTG TA Ts TJ TDV Storage temperature Operating temperature Max. Soldering Temperature (10 sec) Junction Temperature Static Discharge Voltage (As per JEDEC STD22- A114-B)
P2781/82/84
Parameter
Voltage on any pin with respect to Ground
Rating
-0.5 to +4.6 -65 to +125 -40 to +85 260 150 2
Unit
V C C C C KV
Note: These are stress ratings only and are not implied for functional use. Exposure to absolute maximum ratings for prolonged periods of time may affect device reliability.
DC Electrical Characteristics
(Test condition: All parameters are measured at room temperature (+25C) unless otherwise stated)
Symbol
VIL VIH IIL IIH IXOL IXOH VOL VOH IDD ICC VDD Input low voltage
Parameter
Input high voltage Input low current (internal input pull-up resistor on FS0 and FS1) Input high current (internal input pull-up resistor on FS0 and FS1) XOUT output low current XOUT output high current Output low voltage (VDD = 3.3V, IOL = 20mA) Output high voltage (VDD = 3.3V, IOH = 20mA) Static supply current Typical dynamic supply current (25pF scope probe loading) Operating voltage
Min
VSS - 0.3 2.0 2.5 5.2 at 3MHz 3.0
Typ
60 60 10 10 3 3.3
Max
0.8 VDD +0.3 0.4 21.2 at 82MHz 3.6
Unit
V V A A mA mA V V mA mA V
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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October 2006 rev 1.6
AC Electrical Characteristics Symbol
fIN
P2781/82/84
Parameter
Input frequency: P278xA P2781A
Min
3 3 6 12 1 @ 3MHz -20
Typ
1 1 250 0
Max
78 78 156 312 2 @ 82MHz +20
Unit
MHz
fOUT
Output frequency:
P2782A P2784A
tLH tHL tJC tD F
P278xA P278xA P2781A P2781A P278xA
Output rise time (measured at 0.8 V to 2.0 V, 25pF scope probe loading) Output fall time (measured at 2.0 V to 0.8 V, 25 pF scope probe loading) Jitter (cycle to cycle, 6sigma, 1000 sweeps, 0.5% spread, I/O frequency = 16MHz) Output duty cycle deviation (error from 50% duty cycle, 25pF scope probe loading) Frequency deviation tolerance from BW% stated in the Loop Filter Selection Table
nS nS pS % %
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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October 2006 rev 1.6
Package Information 8-Pin SOIC Package
P2781/82/84
E
H
D
A2
A
e B A 1
C L
D
Dimensions
Symbol Min
A1 A A2 B C D E e H L
Inches Max
0.010 0.069 0.059 0.020 0.010 0.004 0.053 0.049 0.012 0.007
Millimeters Min
0.10 1.35 1.25 0.31 0.18 4.90 BSC 3.91 BSC 1.27 BSC 6.00 BSC 0.41 0 1.27 8
Max
0.25 1.75 1.50 0.51 0.25
0.193 BSC 0.154 BSC 0.050 BSC 0.236 BSC 0.016 0 0.050 8
Note: Controlling dimensions are millimeters SOIC - 0.074 grams unit weight
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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October 2006 rev 1.6
8-Pin TSSOP Package
P2781/82/84
H
E D A2 A e B A1 L C
Dimensions Symbol Min
A A1 A2 B c D E e H L 0.020 0 0.002 0.033 0.008 0.004 0.114 0.169 0.026 BSC 0.252 BSC 0.028 8 0.50 0
Inches Max
0.043 0.006 0.037 0.012 0.008 0.122 0.177 0.05 0.85 0.19 0.09 2.90 4.30
Millimeters Min Max
1.10 0.15 0.95 0.30 0.20 3.10 4.50 0.65 BSC 6.40 BSC 0.70 8
Note: Controlling dimensions are millimeters TSSOP - 0.0325 grams unit weight
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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October 2006 rev 1.6
Ordering Codes Ordering #
P278xAF-08ST P278xAF-08SR P278xAF-08TT P278xAF-08TR P278xAG-08ST P278xAG-08SR P278xAG-08TT P278xAG-08TR I278xAF-08ST I278xAF-08SR I278xAF-08TT I278xAF-08TR I278xAG-08ST I278xAG-08SR I278xAG-08TT I278xAG-08TR X278xAF-08ST X278xAF-08SR X278xAF-08TT X278xAF-08TR X278xAG-08ST X278xAG-08SR X278xAG-08TT X278xAG-08TR
Note: x=1/2/4
P2781/82/84
Top Marking
P278xAF P278xAF P278xAF P278xAF P278xAG P278xAG P278xAG P278xAG I278xAF I278xAF I278xAF I278xAF I278xAG I278xAG I278xAG I278xAG X278xAF X278xAF X278xAF X278xAF X278xAG X278xAG X278xAG X278xAG
Package Type
8 PIN SOIC, TUBE, Pb Free 8 PIN SOIC, TAPE AND REEL,Pb Free 8 PIN TSSOP, TUBE, Pb Free 8 PIN TSSOP, TAPE AND REEL, Pb Free 8 PIN SOIC, TUBE, Green 8 PIN SOIC, TAPE AND REEL, Green 8 PIN TSSOP, TUBE, Green 8 PIN TSSOP, TAPE AND REEL, Green 8 PIN SOIC, TUBE, Pb Free 8 PIN SOIC, TAPE AND REEL,Pb Free 8 PIN TSSOP, TUBE, Pb Free 8 PIN TSSOP, TAPE AND REEL, Pb Free 8 PIN SOIC, TUBE, Green 8 PIN SOIC, TAPE AND REEL, Green 8 PIN TSSOP, TUBE, Green 8 PIN TSSOP, TAPE AND REEL, Green 8 PIN SOIC, TUBE, Pb Free 8 PIN SOIC, TAPE AND REEL, Pb Free 8 PIN TSSOP, TUBE, Pb Free 8 PIN TSSOP, TAPE AND REEL, Pb Free 8 PIN SOIC, TUBE, Green 8 PIN SOIC, TAPE AND REEL, Green 8 PIN TSSOP, TUBE, Green 8 PIN TSSOP, TAPE AND REEL, Green
Temperature
Commercial Commercial Commercial Commercial Commercial Commercial Commercial Commercial Industrial Industrial Industrial Industrial Industrial Industrial Industrial Industrial Automotive Automotive Automotive Automotive Automotive Automotive Automotive Automotive
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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October 2006 rev 1.6
Device Ordering Information
P2781/82/84
P278xA
F
08 XX
Package: ST - SOIC, TUBE SR - SOIC, T/R TT - TSSOP, TUBE TR - TSSOP, T/R
Pin Count
F = LEAD FREE or RoHS COMPLIANT PART G = GREEN PACKAGE, LEAD FREE, and RoHS
DEVICE NUMBER
Note: x=1/2/4
Flow: P = Commercial Temperature Range (0C to 70C) I = Industrial Temperature Range (-40C to 85C) X = Automotive Temperature Range (-40C to +125C)
Licensed under US patent #5,488,627, #6,646,463 and #5,631,920
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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October 2006 rev 1.6
P2781/82/84
PulseCore Semiconductor Corporation 1715 S. Bascom Avenue Suite 200, Campbell, CA 95008 Tel # - 408-879-9077 Fax # - 408-879-9018 www.pulsecoresemi.com
Copyright (c) PulseCore Semiconductor All Rights Reserved Part Number: P2781/82/84 Document Version: 1.6
Note: This product utilizes US Patent # 6,646,463 Impedance Emulator Patent issued to PulseCore Semiconductor, dated 11-11-2003
(c) Copyright 2006 PulseCore Semiconductor Corporation. All rights reserved. Our logo and name are trademarks or registered trademarks of PulseCore Semiconductor. All other brand and product names may be the trademarks of their respective companies. PulseCore reserves the right to make changes to this document and its products at any time without notice. PulseCore assumes no responsibility for any errors that may appear in this document. The data contained herein represents PulseCore's best data and/or estimates at the time of issuance. PulseCore reserves the right to change or correct this data at any time, without notice. If the product described herein is under development, significant changes to these specifications are possible. The information in this product data sheet is intended to be general descriptive information for potential customers and users, and is not intended to operate as, or provide, any guarantee or warrantee to any user or customer. PulseCore does not assume any responsibility or liability arising out of the application or use of any product described herein, and disclaims any express or implied warranties related to the sale and/or use of PulseCore products including liability or warranties related to fitness for a particular purpose, merchantability, or infringement of any intellectual property rights, except as express agreed to in PulseCore's Terms and Conditions of Sale (which are available from PulseCore). All sales of PulseCore products are made exclusively according to PulseCore's Terms and Conditions of Sale. The purchase of products from PulseCore does not convey a license under any patent rights, copyrights; mask works rights, trademarks, or any other intellectual property rights of PulseCore or third parties. PulseCore does not authorize its products for use as critical components in life-supporting systems where a malfunction or failure may reasonably be expected to result in significant injury to the user, and the inclusion of PulseCore products in such life-supporting systems implies that the manufacturer assumes all risk of such use and agrees to indemnify PulseCore against all claims arising from such use.
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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