ASM3P2853A November 2006 rev 1.3 Peak EMI Reducing Solution Features shielding that are required to pass EMI regulations. The • Generates an EMI optimized clock signal at ASM3P2853A modulates the output of PLL in order to output. spread the bandwidth of a synthesized clock, thereby • Input frequency: 25MHz. decreasing the peak amplitudes of its harmonics. This • Frequency outputs: results in significantly lower system EMI compared to the • USB Clock (48MHz unmodulated) typical narrow band signal produced by oscillators and • 50MHz (modulated), ±1% centre spread most clock generators. Lowering EMI by increasing a • Modulation rate: 39KHz. signal’s bandwidth is called spread spectrum clock • Spread Spectrum ON/OFF control generation. • Supply voltage range 2.5V ± 5%. • Available in 8 Pin SOIC package. • Commercial and Industrial Temperature range. Applications ASM3P2853A is targeted towards EMI management for Product Description high speed digital applications such as PC peripheral The ASM3P2853A is a versatile spread spectrum devices, consumer electronics and embedded controller frequency systems. modulator. The ASM3P2853A reduces electromagnetic interference (EMI) at the clock source. The ASM3P2853A allows significant system cost savings by reducing the number of circuit board layers and Block Diagram VDD XIN XOUT Crystal Oscillator SSONB PWDNB PLL1 USB Clock (48MHz Unmodulated) PLL2 50MHz Modulated 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. ASM3P2853A November 2006 rev 1.3 Pin Configuration 8 50MHz 7 USB Clock 3 6 SSONB 4 5 PWDNB XIN 1 XOUT 2 VDD VSS ASM3P2853A Pin Description Pin# Pin Name Type 1 XIN I Description Connection to crystal or external reference frequency input. This pin has dual functions. It can be connected either to an external crystal or an external reference clock. Connection to crystal. If using an external reference clock, this pin must be left 2 XOUT O 3 VDD P Power supply for the analog and digital blocks 4 VSS P Ground to entire chip. 5 PWDNB I 6 SSONB I 7 8 USB Clock 50MHz unconnected. Power-down control pin. Pull low to enable the power-down mode. Connect to VDD, if not used. Digital logic input used to enable spread spectrum function (Active LOW). Spread spectrum is enabled when LOW, disabled when HIGH. O Clock output -1 (48MHz unmodulated) O Clock output -2 (50MHz modulated) Peak EMI Reducing Solution Notice: The information in this document is subject to change without notice. 2 of 8 ASM3P2853A November 2006 rev 1.3 Absolute Maximum Ratings Symbol VDD, VIN Parameter Rating Unit Voltage on any pin with respect to Ground -0.5 to +4.6 V 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 TSTG 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. Operating Conditions Parameter Symbol Supply Voltage Condition / Description VDD Ambient Operating 2.5V ± 5% TA Temperature Range Crystal Resonator Frequency Output Driver Load Capacitance Min Typ Max 2.375 2.5 2.625 -40 - +85 FXIN 25 CL - - Unit V °C MHz 15 pF Crystal Specifications Fundamental AT cut parallel resonant crystal Nominal frequency 25MHz Frequency tolerance ± 50ppm or better at 25°C Operating temperature range -25°C to +85°C Storage temperature -40°C to +85°C Load capacitance 18pF Shunt capacitance 7pF maximum ESR 25Ω Peak EMI Reducing Solution Notice: The information in this document is subject to change without notice. 3 of 8 ASM3P2853A November 2006 rev 1.3 DC Electrical Characteristics Parameter Symbol Conditions / Description Min Typ Max Unit IDD VDD=2.5V, FXIN=25MHz, CL=15pF 7 13 20 mA - 12 - uA Overall Supply Current, Dynamic Supply Current, Static IDDL VDD = 2.5V, XIN = 0, PWDNB =0 All input pins High-Level Input Voltage Low-Level Input Voltage High-Level Input Current Low-Level Input Current (pull-up) VIH VDD=2.5V 1.7 - - V VIL VDD=2.5V - - 0.7 V IIH - - 25 µA IIL - - -25 µA Clock Outputs High-Level Output Source Current Low-Level Output Sink Current High-Level Output Source Current Low-Level Output Sink Current Output Impedance IxOH VDD= 2.5V ,V(XIN) = 0, VO=2V - -15 - mA IxOL VDD= V(XIN) =2.5V, VO=0.4V - 15 - mA IOH VO=2V - 8 - mA IOL VO=0.4V - 8 - mA - 42 - Ω ZO Peak EMI Reducing Solution Notice: The information in this document is subject to change without notice. 4 of 8 ASM3P2853A November 2006 rev 1.3 AC Electrical Characteristics Parameter Symbol Rise Time* tr Fall Time* tf Conditions/ Description Min Typ Max Unit - 2 - nS - 1.5 - nS tjc - 250 - pS tp - 175 - pS 45 50 55 % Measured from 20% to 80% of the signal level Measured from 80% to 20% of the Jitter (Cycle to Cycle) Jitter (Period) signal level Ratio of pulse width (as measured from Clock Duty Cycle td rising edge to next falling edge at VDD/2) to one clock period * CL = 15 pF, Input clock frequency = 25MHz Typical Application Schematic using ASM3P2853A Device 25MHz fundamental Crystal 1 XIN 2 XOUT 3 VDD 4 50MHz 8 Modulated 50MHz output 27pF USB Clock 7 SSONB 6 VSS PWDNB ASM3P2853A 5 Un-modulated 48MHz output 27pF +2.5V 0.1uF Peak EMI Reducing Solution Notice: The information in this document is subject to change without notice. 5 of 8 ASM3P2853A November 2006 rev 1.3 Package Information 8-Pin SOIC package H E D A2 A C A1 D θ e L B Dimensions Symbol Inches Min Max Millimeters 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° Coplanarity < = 4 mil Peak EMI Reducing Solution Notice: The information in this document is subject to change without notice. 6 of 8 ASM3P2853A November 2006 rev 1.3 Ordering Codes Part number Marking Package Configuration Temperature Range ASM3P2853AF-08ST 3P2853AF 8-pin SOIC ,TUBE, Pb Free Commercial ASM3P2853AF-08SR 3P2853AF 8-pin SOIC, TAPE & REEL, Pb Free Commercial ASM3P2853AG-08ST 3P2853AG 8-pin SOIC ,TUBE, Green Commercial ASM3P2853AG-08SR 3P2853AG 8-pin SOIC, TAPE & REEL, Green Commercial ASM3I2853AF-08ST 3I2853AF 8-pin SOIC ,TUBE, Pb Free Industrial ASM3I2853AF-08SR 3I2853AF 8-pin SOIC, TAPE & REEL, Pb Free Industrial ASM3I2853AG-08ST 3I2853AG 8-pin SOIC ,TUBE, Green Industrial ASM3I2853AG-08SR 3I2853AG 8-pin SOIC, TAPE & REEL, Green Industrial Device Ordering Information A S M 3 P 2 8 5 3 A F - 0 8 S R R = Tape & Reel, T = Tube or Tray O = SOT S = SOIC T = TSSOP A = SSOP V = TVSOP B = BGA Q = QFN U = MSOP E = TQFP L = LQFP U = MSOP P = PDIP D = QSOP X = SC-70 DEVICE PIN COUNT F = LEAD FREE AND RoHS COMPLIANT PART G = GREEN PACKAGE, LEAD FREE, and RoHS PART NUMBER X= Automotive I= Industrial P or n/c = Commercial (-40C to +125C) (-40C to +85C) (0C to +70C) 1 = Reserved 2 = Non PLL based 3 = EMI Reduction 4 = DDR support products 5 = STD Zero Delay Buffer 6 = Power Management 7 = Power Management 8 = Power Management 9 = Hi Performance 0 = Reserved PulseCore Semiconductor Mixed Signal Product Licensed under US patent #5,488,627, #6,646,463 and #5,631,920. Peak EMI Reducing Solution Notice: The information in this document is subject to change without notice. 7 of 8 ASM3P2853A November 2006 rev 1.3 PulseCore Semiconductor Corporation 1715 S. Bascom Ave Suite 200 Campbell, CA 95008 Tel: 408-879-9077 Fax: 408-879-9018 www.pulsecoresemi.com Copyright © PulseCore Semiconductor All Rights Reserved Preliminary Information Part Number: ASM3P2853A Document Version: v1.3 Note: This product utilizes US Patent # 6,646,463 Impedance Emulator Patent issued to PulseCore Semiconductor, dated 11-11-2003 © 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. Peak EMI Reducing Solution Notice: The information in this document is subject to change without notice. 8 of 8