General Description

The CGS3311, CGS3312, CGS3313, CGS3314, CGS3315, CGS3316, CGS3317, CGS3318 and CGS3319 devices are designed for Clock Generation and Support (CGS) applications up to 110 MHz. The CGS331x series of devices are crystal controlled CMOS oscillators requiring a minimum of external components. The 331x devices provide selectable output divide ratio (and selectable crystal drive level). The circuit is designed to operate over a wide frequency range using fundamental model or overtone crystals.

Features

■ Fairchild’s CGS family of devices for high frequency

clock source applications

■ Crystal frequency operation range:

fundamental: 10 MHz to 100 MHz typical

3rd or 5th overtone: 10 MHz to 85 MHz

■ Programmable oscillator drive

■ Selectable fast output edge rates

■ Output symmetry circuit to adjust 50 duty cycle point

between CMOS and TTL levels

■ Output current drive of 48 mA for IOL/IOH

■ FACT CMOS output levels

■ Output has high speed short circuit protection

■ Basic oscillator type: Pierce

■ Hysteresis inputs to improve noise margin