ICS8431AM-21LFT

ICS8431AM-21LFT Datasheet

ICS8431-21

Part	Datasheet
ICS8431AM-21LFT	ICS8431AM-21LFT (pdf)

Related Parts	Information
ICS8431AM-21LF	ICS8431AM-21LF

PDF Datasheet Preview
350MHZ, Low Jitter, Crystal Oscillator-to-3.3V LVPECL Frequency Synthesizer PRODUCT DISCONTINUATION NOTICE - LAST TIME BUY EXPIRES ON JULY 26, 2014 ICS8431-21 The ICS8431-21 is a general purpose clock frequency synthesizer for IA64/32 application. The VCO operates at a frequency range of 250MHz to 700MHz providing an output frequency range of 62.5MHz to 350MHz. The output frequency can be programmed using the parallel interface, M0 through M8 to the configuration logic, and the output divider control pin, DIV_SEL. Spread spectrum clocking is programmed via the control inputs SSC_CTL0 and SSC_CTL1. Programmable features of the ICS8431-21 support four operational modes. The four modes are spread spectrum clocking SSC , non-spread spectrum clock and two test modes which are controlled by the SSC_CTL[1:0] pins. Unlike other synthesizers, the ICS8431-21 can immediately change spread-spectrum operation without having to reset the device. In SSC mode, the output clock is modulated in order to achieve a reduction in EMI. In one of the PLL bypass test modes, the PLL is disconnected as the source to the differential output allowing an external source to be connected to the TEST_I/O pin. This is useful for in-circuit testing and allows the differential output to be driven at a lower frequency throughout the system clock tree. In the other PLL bypass mode, the oscillator divider is used as the source to both the M and the Fout divide by This is useful for characterizing the oscillator and internal dividers. • Fully integrated PLL • Differential 3.3V LVPECL output • Crystal oscillator interface • Output frequency range 62.5MHz to 350MHz • Crystal input frequency range 14MHz to 25MHz • VCO range 250MHz to 700MHz • Programmable PLL loop divider for generating a variety of output frequencies • Spread Spectrum Clocking SSC fixed at 1/2% modulation for environments requiring ultra low EMI • PLL bypass modes supporting in-circuit testing and on-chip functional block characterization • Cycle-to-cycle jitter 30ps maximum • 3.3V supply voltage • 0°C to 85°C ambient operating temperature • Replaces ICS8431-01 and ICS8431-11 • Available in both standard RoHS 5 and lead-free RoHS 6 packages • Use Replacement Part 84314AY-02LF BLOCK DIAGRAM XTAL_IN XTAL_OUT OSC ÷ 16 PHASE DETECTOR VCO ÷4 M0:M8 Configuration Logic SSC Control Logic FOUT nFOUT TEST_I/O nP_LOAD SSC_CTL0 SSC_CTL1 DIV_SEL IDT / ICS 3.3V LVPECL FREQUENCY SYNTHESIZER PIN ASSIGNMENT M0 1 M1 2 M2 3 M3 4 M4 5 M5 6 M6 7 M7 8 M8 9 SSC_CTL0 10 SSC_CTL1 11 VEE 12 TEST_I/O 13 VCC 14 28 nP_LOAD 27 VCC 26 XTAL_IN 25 XTAL_OUT 24 nc 23 nc 22 VCCA 21 VEE 20 MR 19 DIV_SEL 18 VCCO 17 FOUT 16 nFOUT 15 VEE ICS8431-21 28-Lead SOIC 7.5mm x 18.05mm x 2.25mm package body M Package Top View ICS8431-21 350MHZ, LOW JITTER, CRYSTAL OSCILLATOR-TO-3.3V LVPECL FREQUENCY SYNTHESIZER FUNCTIONAL DESCRIPTION The ICS8431-21 features a fully integrated PLL and therefore requires no external components for setting the loop bandwidth. The output of the oscillator is divided by 16 prior to the phase detector. With a 16MHz crystal this provides a 1MHz reference frequency. The VCO of the PLL operates over a range of 250MHz to 700MHz. The output of the M divider is also applied to the phase detector. The phase detector and the M divider force the VCO output frequency to be M times the reference frequency by adjusting the VCO control voltage. Note that for some values of M either too high or too low , the PLL will not achieve lock. The output of the VCO is scaled by a divider prior to being sent to the LVPECL output buffer. The divider provides a 50% output duty cycle. TABLE ORDERING INFORMATION Part/Order Number Marking Package Shipping Packaging Temperature ICS8431AM-21 ICS8431AM-21 28 Lead SOIC Tube 0°C to 85°C ICS8431AM-21T ICS8431AM-21 28 Lead SOIC 1000 Tape & Reel 0°C to 85°C ICS8431AM-21LF ICS8431AM-21LF 28 Lead "Lead-Free" SOIC Tube 0°C to 85°C ICS8431AM-21LFT ICS8431AM-21LF 28 Lead "Lead-Free" SOIC 1000 Tape & Reel 0°C to 85°C NOTE Parts that are ordered with an "LF" suffix to the part number are the Pb-Free configuration and are RoHS compliant. While the information presented herein has been checked for both accuracy and reliability, Integrated Device Technology, Incorporated IDT assumes no responsibility for either its use or for infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use in normal commercial applications. Any other applications such as those requiring extended temperature ranges, high reliability or other extraordinary environmental requirements are not recommended without additional processing by IDT. IDT reserves the right to change any circuitry or specifications without notice. IDT does not authorize or warrant any IDT product for use in life support devices or critical medical instruments. IDT / ICS 3.3V LVPECL FREQUENCY SYNTHESIZER ICS8431-21 350MHZ, LOW JITTER, CRYSTAL OSCILLATOR-TO-3.3V LVPECL FREQUENCY SYNTHESIZER Table T10 Page 1 16 9 10 18 Description of Change Features Section - added replacement bullet and Lead-Free bullet Ordering Information Table - added Lead-Free part number. Added LVCMOS to XTAL Interface section. Recommendations for Unused Input Pins section. Ordering Information Table - added LF marking. Updated format throughout the datasheet. Not Recommended For New Designs PDN# CQ-13-01, Product Discontinuation Notice - Last Time Buy Expires July 26, 2014 Date 4/27/05 5/30/07 6/21/13 8/22/13 IDT / ICS 3.3V LVPECL FREQUENCY SYNTHESIZER ICS8431-21 350MHZ, LOW JITTER, CRYSTAL OSCILLATOR-TO-3.3V LVPECL FREQUENCY SYNTHESIZER We’ve Got Your Timing Solution. 6024 Silver Creek Valley Road San Jose, CA 95138 Sales 800-345-7015 inside USA +408-284-8200 outside USA Fax 408-284-2775 Tech Support +480-763-2056 DISCLAIMER Integrated Device Technology, Inc. IDT and its subsidiaries reserve the right to modify the products and/or specifications described herein at any time and at IDT’s sole discretion. All information in this document, including descriptions of product features and performance, is subject to change without notice. Performance specifications and the operating parameters of the described products are determined in the independent state and are not guaranteed to perform the same way when installed in customer products. The information contained herein is provided without representation or warranty of any kind, whether express or implied, including, but not limited to, the suitability of IDT’s products for any particular purpose, an implied warranty of merchantability, or non-infringement of the intellectual property rights of others. This document is presented only as a guide and does not convey any license under intellectual property rights of IDT or any third parties. IDT’s products are not intended for use in applications involving extreme environmental conditions or in life support systems or similar devices where the failure or malfunction of an IDT product can be reasonably expected to significantly affect the health or safety of users. Anyone using an IDT product in such a manner does so at their own risk, absent an express, written agreement by IDT. Integrated Device Technology, IDT and the IDT logo are registered trademarks of IDT. Other trademarks and service marks used herein, including protected names, logos and designs, are the property of IDT or their respective third party owners. Copyright All rights reserved.

PDF Datasheet Preview

350MHZ, Low Jitter, Crystal Oscillator-to-3.3V LVPECL Frequency Synthesizer

PRODUCT DISCONTINUATION NOTICE - LAST TIME BUY EXPIRES ON JULY 26, 2014

ICS8431-21

The ICS8431-21 is a general purpose clock frequency synthesizer for IA64/32 application. The VCO operates at a frequency range of 250MHz to 700MHz providing an output frequency range of 62.5MHz to 350MHz. The output frequency can be programmed using the parallel interface, M0 through M8 to the configuration logic, and the output divider control pin, DIV_SEL. Spread spectrum clocking is programmed via the control inputs SSC_CTL0 and SSC_CTL1.

Programmable features of the ICS8431-21 support four operational modes. The four modes are spread spectrum clocking SSC , non-spread spectrum clock and two test modes which are controlled by the SSC_CTL[1:0] pins. Unlike other synthesizers, the ICS8431-21 can immediately change spread-spectrum operation without having to reset the device.

In SSC mode, the output clock is modulated in order to achieve a reduction in EMI. In one of the PLL bypass test modes, the PLL is disconnected as the source to the differential output allowing an external source to be connected to the TEST_I/O pin. This is useful for in-circuit testing and allows the differential output to be driven at a lower frequency throughout the system clock tree. In the other PLL bypass mode, the oscillator divider is used as the source to both the M and the Fout divide by This is useful for characterizing the oscillator and internal dividers.
• Fully integrated PLL
• Differential 3.3V LVPECL output
• Crystal oscillator interface
• Output frequency range 62.5MHz to 350MHz
• Crystal input frequency range 14MHz to 25MHz
• VCO range 250MHz to 700MHz
• Programmable PLL loop divider for generating a variety
of output frequencies
• Spread Spectrum Clocking SSC fixed at 1/2% modulation for environments requiring ultra low EMI
• PLL bypass modes supporting in-circuit testing and on-chip functional block characterization
• Cycle-to-cycle jitter 30ps maximum
• 3.3V supply voltage
• 0°C to 85°C ambient operating temperature
• Replaces ICS8431-01 and ICS8431-11
• Available in both standard RoHS 5 and lead-free RoHS 6
packages
• Use Replacement Part 84314AY-02LF

BLOCK DIAGRAM

XTAL_IN XTAL_OUT

OSC ÷ 16

PHASE

DETECTOR

VCO ÷4

M0:M8

Configuration Logic

SSC Control Logic

FOUT nFOUT

TEST_I/O
nP_LOAD

SSC_CTL0 SSC_CTL1 DIV_SEL

IDT / ICS 3.3V LVPECL FREQUENCY SYNTHESIZER

PIN ASSIGNMENT

M0 1 M1 2 M2 3 M3 4 M4 5 M5 6 M6 7 M7 8 M8 9 SSC_CTL0 10 SSC_CTL1 11 VEE 12 TEST_I/O 13 VCC 14
28 nP_LOAD 27 VCC 26 XTAL_IN 25 XTAL_OUT 24 nc
23 nc 22 VCCA 21 VEE 20 MR 19 DIV_SEL 18 VCCO 17 FOUT
16 nFOUT 15 VEE

ICS8431-21
28-Lead SOIC 7.5mm x 18.05mm x 2.25mm package body

M Package Top View

ICS8431-21 350MHZ, LOW JITTER, CRYSTAL OSCILLATOR-TO-3.3V LVPECL FREQUENCY SYNTHESIZER

FUNCTIONAL DESCRIPTION

The ICS8431-21 features a fully integrated PLL and therefore requires no external components for setting the loop bandwidth. The output of the oscillator is divided by 16 prior to the phase detector. With a 16MHz crystal this provides a 1MHz reference frequency. The VCO of the PLL operates over a range of 250MHz to 700MHz. The output of the M divider is also applied to the phase detector.

The phase detector and the M divider force the VCO output frequency to be M times the reference frequency by adjusting the VCO control voltage. Note that for some values of M either too high or too low , the PLL will not achieve lock. The output of the VCO is scaled by a divider prior to being sent to the LVPECL output buffer. The divider provides a 50% output duty cycle.
TABLE ORDERING INFORMATION

Part/Order Number

Marking

Package

Shipping Packaging Temperature

ICS8431AM-21

ICS8431AM-21
28 Lead SOIC

Tube
0°C to 85°C

ICS8431AM-21T

ICS8431AM-21
28 Lead SOIC
1000 Tape & Reel
0°C to 85°C

ICS8431AM-21LF

ICS8431AM-21LF
28 Lead "Lead-Free" SOIC

Tube
0°C to 85°C

ICS8431AM-21LFT

ICS8431AM-21LF
28 Lead "Lead-Free" SOIC 1000 Tape & Reel
0°C to 85°C

NOTE Parts that are ordered with an "LF" suffix to the part number are the Pb-Free configuration and are RoHS compliant.

While the information presented herein has been checked for both accuracy and reliability, Integrated Device Technology, Incorporated IDT assumes no responsibility for either its use or for infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use in normal commercial applications. Any other applications such as those requiring extended temperature ranges, high reliability or other extraordinary environmental requirements are not recommended without additional processing by IDT. IDT reserves the right to change any circuitry or specifications without notice. IDT does not authorize or warrant any IDT product for use in life support devices or critical medical instruments.

IDT / ICS 3.3V LVPECL FREQUENCY SYNTHESIZER

ICS8431-21 350MHZ, LOW JITTER, CRYSTAL OSCILLATOR-TO-3.3V LVPECL FREQUENCY SYNTHESIZER

Table T10

Page 1 16 9 10 18
Description of Change Features Section - added replacement bullet and Lead-Free bullet Ordering Information Table - added Lead-Free part number. Added LVCMOS to XTAL Interface section. Recommendations for Unused Input Pins section. Ordering Information Table - added LF marking. Updated format throughout the datasheet. Not Recommended For New Designs PDN# CQ-13-01, Product Discontinuation Notice - Last Time Buy Expires July 26, 2014

Date 4/27/05
5/30/07
6/21/13 8/22/13

IDT / ICS 3.3V LVPECL FREQUENCY SYNTHESIZER

ICS8431-21 350MHZ, LOW JITTER, CRYSTAL OSCILLATOR-TO-3.3V LVPECL FREQUENCY SYNTHESIZER

We’ve Got Your Timing Solution.
6024 Silver Creek Valley Road San Jose, CA 95138

Sales 800-345-7015 inside USA +408-284-8200 outside USA Fax 408-284-2775

Tech Support +480-763-2056

DISCLAIMER Integrated Device Technology, Inc. IDT and its subsidiaries reserve the right to modify the products and/or specifications described herein at any time and at IDT’s sole discretion. All information in this document, including descriptions of product features and performance, is subject to change without notice. Performance specifications and the operating parameters of the described products are determined in the independent state and are not guaranteed to perform the same way when installed in customer products. The information contained herein is provided without representation or warranty of any kind, whether express or implied, including, but not limited to, the suitability of IDT’s products for any particular purpose, an implied warranty of merchantability, or non-infringement of the intellectual property rights of others. This document is presented only as a guide and does not convey any license under intellectual property rights of IDT or any third parties.

IDT’s products are not intended for use in applications involving extreme environmental conditions or in life support systems or similar devices where the failure or malfunction of an IDT product can be reasonably expected to significantly affect the health or safety of users. Anyone using an IDT product in such a manner does so at their own risk, absent an express, written agreement by IDT.

Integrated Device Technology, IDT and the IDT logo are registered trademarks of IDT. Other trademarks and service marks used herein, including protected names, logos and designs, are the property of IDT or their respective third party owners.

Copyright All rights reserved.

Notice: we do not provide any warranties that information, datasheets, application notes, circuit diagrams, or software stored on this website are up-to-date or error free. The archived ICS8431AM-21LFT Datasheet file may be downloaded here without warranties.

Datasheet ID: ICS8431AM-21LFT 637106