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Jan 2003

FS8108 Low Power Phase-Locked Loop IC

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tained in this datasheet is subject to change without prior notice. Princeton Technology Corp. assumes no responsibility

for the use of any circuits shown in this datasheet.

Description

The FS8108 is a serial data input, phase-locked loop IC with programmable input and ref-

erence frequency dividers. When combined with a VCO, the FS8108 becomes the core of

a very low power frequency synthesizer well-suited for mobile communication applica-

tions such as paging systems. The FS8108 includes an 18-bit programmable input fre-

quency divider and also implements a separate pin for stand-by control.

Features

High maximum input operating frequency — 185 MHz at V

Up to 22 MHz internal crystal oscillator reference frequency at V

Extremely low current consumption (I

18-bit programmable input frequency divider (including a

÷ 64/65 prescaler) with

divide ratio range from 4032 to 262143

13-bit programmable reference frequency divider (including a

÷ 8 prescaler) with

divide ratio range from 40 to 65528

Optional lock detector output

Charge pump output for passive low-pass filter

Quick-lock signal output for faster locking

Separate pin for stand-by control

TSSOP 16L package (0.65mm pitch)

Applications

Pager

Wireless communication system