P2781 PULSECORE | Alldatasheet

Document overview

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Technical content

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. 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 reduces electromagnetic inte rference (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.

Applications

The P278xA is targeted towa rds MFP, xDSL, fax modem, set-top box, USB controller, DSC, and embedded systems. Block Diagram Crystal Oscillator Frequency Divider Feedback Divider Phase Detector Modulation Output Divider VCO XIN /CLKIN XOUT FS0 FS1 LF VDD VSS PLL ModOUT

rev 1.6 General Purpose EMI Reduction IC 2 of 11 Notice: The information in this document is subject to change without notice. Pin Configuration Pin Description (P278xA) Pin# Pin Name Type Description 1 XIN/CLKIN I 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. 2 XOUT O Crystal connection. If using an external reference, this pin must be left unconnected.

3 FS1 I

Digital logic input used to select input frequency range (see the Input Frequency Selection Table). This pin has an internal pull-up resistor.

4 LF I

External Loop Filter for the PLL. By changing the value of the CRC circuit, the percentage spread can be adjusted accord ingly. See the Loop Filter Selection Table for detail value. 5 VSS I Ground Connection. Connect to system ground. 6 ModOUT O Spread Spectrum Clock Output.

7 FS0 I

Digital logic input used to select input frequency range (see the Input Frequency Selection Table). This pin has an internal pull-up resistor. 8 VDD P Connect to +3.3 V Input Frequency Selection Table Output Frequency Scaling (MHz) FS1 FS0 Input (MHz) P2781A P2782A P2784A Modulation Rate (KHz) 0 0 3 to 9 3 to 9 6 to 18 12 to 36 Fin / 128 0 1 10 to 19 10 to 19 20 to 38 40 to 76 Fin / 256 1 0 20 to 38 20 to 38 40 to 76 80 to 152 Fin / 512 1 1 39 to 78 39 to 78 78 to 156 156 to 312 Fin / 1024 Standard pin Configuration offered in both 8 pin SOIC and TSSOP Packages FS1 LF FS0 VDD VSS 4 5 P278xA XIN / CLKIN ModOUT XOUT

rev 1.6 General Purpose EMI Reduction IC 3 of 11 Notice: The information in this document is subject to change without notice. Loop Filter Selection Table VDD 3.3V 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% BW = ±0.75% BW = ±1.00% BW = ±1.25% Input MHz FS1 FS0 C1 (pF) (pF) (ohm) (pF) (pF) (ohm) (pF) (pF) (ohm) (pF) (pF) (ohm) 3 0 0 270 330,000 220 270 330,000 300 270 100,000 390 560 100,000 510 4 0 0 270 100,000 270 270 100,000 390 270 100,000 560 560 100,000 680 5 0 0 270 100,000 390 270 100,000 560 270 100,000 750 560 100,000 910 6 0 0 270 100,000 510 270 100,000 750 270 10,000 1,000 680 6,800 1,200 7 0 0 270 100,000 620 270 100,000 1,000 270 5,600 1,200 330 3,300 1,200 8 0 0 270 100,000 820 270 100,000 1,200 270 12,000 2,200 680 6,800 2,200 9 0 0 270 100,000 1,000 270 100,000 1,500 270 5,600 2,200 270 2,700 2,200 10 0 1 270 100,000 330 270 100,000 510 270 100,000 750 560 100,000 910 11 0 1 270 100,000 390 270 100,000 560 270 100,000 866(1%) 560 100,000 1,100 12 0 1 270 100,000 510 270 100,000 750 270 10,000 1,000 680 6,800 1,200 13 0 1 270 100,000 560 270 100,000 820 270 12,000 1,200 470 4,700 1,200 14 0 1 270 100,000 620 270 100,000 1,000 270 5,600 1,200 330 3,300 1,200 15 0 1 270 100,000 750 270 100,000 1,100 270 3,900 1,200 330 3,300 1,500 16 0 1 270 100,000 820 270 100,000 1,200 270 12,000 2,200 680 6,800 2,200 17 0 1 270 100,000 910 270 100,000 1,300 270 10,000 2,200 390 3,900 2,200 18 0 1 270 100,000 1,000 270 100,000 1,500 270 5,600 2,200 270 2,700 2,200 19 0 1 270 100,000 1,200 270 100,000 1,600 270 3,300 2,200 270 2,700 2,700 20 0 0 270 100,000 330 270 100,000 560 270 100,000 750 560 100,000 910 21-22 1 0 270 100,000 390 270 100,000 620 270 100,000 866 (1%) 560 100,000 1,100 23-24 1 0 270 100,000 510 270 100,000 750 270 10,000 1,000 680 6,800 1,200 25-26 1 0 270 100,000 560 270 100,000 820 270 12,000 1,200 470 4,700 1,200 27-28 1 0 270 100,000 620 270 100,000 1,000 270 6,800 1,200 330 3,300 1,200 29-30 1 0 270 100,000 750 270 100,000 1,100 270 3,900 1,200 330 3,300 1,500 31-32 1 0 270 100,000 820 270 100,000 1,200 270 12,000 2,200 680 6,800 2,200 33-34 1 0 270 100,000 910 270 100,000 1,300 270 10,000 2,200 390 3,900 2,200 35-36 1 0 270 100,000 1,000 270 100,000 1,500 270 5,600 2,200 270 2,700 2,200 37-38 1 0 270 100,000 1,200 270 100,000 1,600 270 3,300 2,200 270 2,700 2,700 39-42 1 1 270 100,000 330 270 100,000 560 270 100,000 750 560 100,000 910 43-46 1 1 270 100,000 390 270 100,000 620 270 100,000 866 (1%) 560 100,000 1,100 47-50 1 1 270 100,000 510 270 100,000 750 270 10,000 1,000 680 6,800 1,200 51-54 1 1 270 100,000 560 270 100,000 820 270 12,000 1,200 470 4,700 1,200 55-58 1 1 270 100,000 620 270 100,000 1,000 270 6,800 1,200 330 3,300 1,200 59-62 1 1 270 100,000 750 270 100,000 1,100 270 3,900 1,200 330 3,300 1,500 63-66 1 1 270 100,000 820 270 100,000 1,200 270 12,000 2,200 680 6,800 2,200 67-70 1 1 270 100,000 910 270 100,000 1,300 270 8,200 2,200 390 3,900 2,200 71-74 1 1 270 100,000 1,000 270 100,000 1,600 270 5,600 2,200 270 2,700 2,200 75-78 1 1 270 100,000 1,200 270 100,000 1,800 270 3,300 2,200 270 2,700 2,700

1 The BW value is representative of typical conditions

rev 1.6 General Purpose EMI Reduction IC 4 of 11 Notice: The information in this document is subject to change without notice. Spread Spectrum Selection The P278xA performs Zero Cycle Slip when set at low percentag e spreading. This allows no occurrence of system timing error. The optimal setting should minimize system EMI to the fullest without affect ing 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, noteb ook PC, and LCD monitor applications. It is optimized for operation between 3 to 78MHz range. In the following applic ation schematic example, t he P2781A spread percentage selection is determined by the external LF value specified in the Loop Filter Selection Tabl e. 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. Note: Both logic input pins FS1 and FS0 have to be connected to either VDD or VSS. Do not leave them floating. VDD FS0 ModOUT VSSLF FS1 XOUT XIN/CLKIN P278xA +3.3V Modulated 16MHz Clock To target Chip

16 MHz

0.1µF C2 C1

0 Ohm

2.2 K

rev 1.6 General Purpose EMI Reduction IC 5 of 11 Notice: The information in this document is subject to change without notice. Absolute Maximum Ratings Symbol Parameter Rating Unit VDD, VIN Voltage on any pin with respect to Ground -0.5 to +4.6 V TSTG Storage temperature -65 to +125 °C TA Operating temperature -40 to +85 °C Ts Max. Soldering Temperature (10 sec) 260 °C TJ Junction Temperature 150 °C TDV Static Discharge Voltage (As per JEDEC STD22- A114-B) 2 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. (Test condition: All parameters are measured at room temperature (+25°C) unless otherwise stated) Symbol Parameter Min Typ Max Unit VIL Input low voltage VSS – 0.3 - 0.8 V VIH Input high voltage 2.0 - VDD +0.3 V IIL Input low current (internal input pull-up resistor on FS0 and FS1) - 60 - µA IIH Input high current (internal input pull-up resistor on FS0 and FS1) - 60 - µA IXOL XOUT output low current - 10 - mA IXOH XOUT output high current - 10 - mA VOL Output low voltage (VDD = 3.3V, I OL = 20mA) - - 0.4 V VOH Output high voltage (VDD = 3.3V, I OH = 20mA) 2.5 - - V IDD Static supply current - 3 - mA ICC Typical dynamic supply current (25pF scope probe loading) 5.2 at 3MHz - 21.2 at 82MHz mA VDD Operating volta ge 3.0 3.3 3.6 V

rev 1.6 General Purpose EMI Reduction IC 6 of 11 Notice: The information in this document is subject to change without notice. Symbol Parameter Min Typ Max Unit fIN Input frequency: P278xA 3 - 78 P2781A 3 - 78 P2782A 6 - 156 fOUT Output frequency: P2784A 12 - 312 MHz tLH P278xA Output rise time (measured at 0.8 V to 2.0 V, 25pF scope probe loading) - 1 - nS tHL P278xA Output fall time (measured at 2.0 V to 0.8 V, 25 pF scope probe loading) - 1 - nS tJC P2781A Jitter (cycle to cycle, ± 6sigma, 1000 sweeps, ± 0.5% spread, I/O frequency = 16MHz) - ±250 - pS tD P2781A Output duty cycle deviation (error from 50% duty cycle, 25pF scope probe loading) ±1 @ 3MHz - ±2 @ 82MHz % ∆F P278xA Frequency deviation tolerance from BW% stated in the Loop Filter Selection Table -20 0 +20 %

rev 1.6 General Purpose EMI Reduction IC 7 of 11 Notice: The information in this document is subject to change without notice.

Package Information

D E H D A2 A θ L C B e Dimensions Inches Millimeters Symbol Min Max Min Max A1 0.004 0.010 0.10 0.25 A 0.053 0.069 1.35 1.75 A2 0.049 0.059 1.25 1.50 B 0.012 0.020 0.31 0.51 C 0.007 0.010 0.18 0.25 D 0.193 BSC 4.90 BSC E 0.154 BSC 3.91 BSC e 0.050 BSC 1.27 BSC H 0.236 BSC 6.00 BSC L 0.016 0.050 0.41 1.27 θ 0° 8° 0° 8° Note: Controlling dimensions are millimeters SOIC - 0.074 grams unit weight

rev 1.6 General Purpose EMI Reduction IC 8 of 11 Notice: The information in this document is subject to change without notice. E H A D B C L θ e 8-Pin TSSOP Package Dimensions Inches Millimeters Symbol Min Max Min Max A 0.043 1.10 A1 0.002 0.006 0.05 0.15 A2 0.033 0.037 0.85 0.95 B 0.008 0.012 0.19 0.30 c 0.004 0.008 0.09 0.20 D 0.114 0.122 2.90 3.10 E 0.169 0.177 4.30 4.50 e 0.026 BSC 0.65 BSC H 0.252 BSC 6.40 BSC L 0.020 0.028 0.50 0.70 θ 0° 8° 0° 8° Note: Controlling dimensions are millimeters TSSOP - 0.0325 grams unit weight

rev 1.6 General Purpose EMI Reduction IC 9 of 11 Notice: The information in this document is subject to change without notice. Ordering Codes Ordering # Top Marking Package Type Temperature P278xAF-08ST P278xAF 8 PIN SOIC, TUBE, Pb Free Commercial P278xAF-08SR P278xAF 8 PIN SOIC, TAPE AND REEL,Pb Free Commercial P278xAF-08TT P278xAF 8 PIN TSSOP, TUBE, Pb Free Commercial P278xAF-08TR P278xAF 8 PIN TSSOP, TAPE AND REEL, Pb Free Commercial P278xAG-08ST P278xAG 8 PIN SOIC, TUBE, Green Commercial P278xAG-08SR P278xAG 8 PIN SOIC, TAPE AND REEL, Green Commercial P278xAG-08TT P278xAG 8 PIN TSSOP, TUBE, Green Commercial P278xAG-08TR P278xAG 8 PIN TSSOP, TAPE AND REEL, Green Commercial I278xAF-08ST I278xAF 8 PIN S OIC, TUBE, Pb Free Industrial I278xAF-08SR I278xAF 8 PIN SOIC, TAPE AND REEL,Pb Free Industrial I278xAF-08TT I278xAF 8 PIN TSSO P, TUBE, Pb Free Industrial I278xAF-08TR I278xAF 8 PI N TSSOP, TAPE AND REEL, Pb Free Industrial I278xAG-08ST I278xAG 8 PIN SOIC, TUBE, Green Industrial I278xAG-08SR I278xAG 8 PIN SOIC, TAPE AND REEL, Green Industrial I278xAG-08TT I278xAG 8 PIN T SSOP, TUBE, Green Industrial I278xAG-08TR I278xAG 8 PIN TSSOP, TAPE AND REEL, Green Industrial X278xAF-08ST X278xAF 8 PIN S OIC, TUBE, Pb Free Automotive X278xAF-08SR X278xAF 8 PIN SOIC, TAPE AND REEL, Pb Free Automotive X278xAF-08TT X278xAF 8 PIN TSSOP, TUBE, Pb Free Automotive X278xAF-08TR X278xAF 8 PIN TSSOP, TAPE AND REEL, Pb Free Automotive X278xAG-08ST X278xAG 8 PIN SOIC, TUBE, Green Automotive X278xAG-08SR X278xAG 8 PIN SOIC, TAPE AND REEL, Green Automotive X278xAG-08TT X278xAG 8 PIN TSSOP, TUBE, Green Automotive X278xAG-08TR X278xAG 8 PIN TSSOP, TAPE AND REEL, Green Automotive Note: x=1/2/4

rev 1.6 General Purpose EMI Reduction IC 10 of 11 Notice: The information in this document is subject to change without notice. Device Ordering Information P278xA F 08 XX Note: x=1/2/4 Licensed under US patent #5,488,627, #6,646,463 and #5,631,920 Package: ST – SOIC, TUBE SR - SOIC, T/R TT – TSSOP, TUBE TR - TSSOP, T/R DEVICE NUMBER Flow: P = Commercial Temperature Range (0°C to 70°C) I = Industrial Temperature Range (-40°C to 85°C) X = Automotive Temperature Range (-40°C to +125°C) Pin Count F = LEAD FREE or RoHS COMPLIANT PART G = GREEN PACKAGE, LEAD FREE, and RoHS

rev 1.6 General Purpose EMI Reduction IC 11 of 11 Notice: The information in this document is subject to change without notice. © Copyright 2006 PulseCore Semiconductor Corporation. All rights reserved. Our logo and name are trademarks or registered trademarks of PulseCore Semiconductor. All ot her 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 t hat 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 descri bed 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 in tended 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 app lication or use of any product described herein, and disclaims any express or implied warrant ies related to the sale and/or use of PulseCore products including liability or warranties related to fitness for a particular purpose, mercha ntability, or infringement of any intellec tual 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 exclusiv ely 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 intellect ual property rights of PulseCore or third partie s. 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 PulseC ore 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. PulseCore Semiconductor Corporation 1715 S. Bascom Avenue Suite 200, Campbell, CA 95008 Tel # - 408-879-9077 Fax # - 408-879-9018 www.pulsecoresemi.com Copyright © 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