ST49C107A Datasheet, PDF (1/8 Pages) Exar Corporation – Preprogrammed CPU Mother Board Frequency Generator

Preliminary
ST49C107A-04
Preprogrammed CPU Mother Board
...the analog plus company^TM
Frequency Generator
FEATURES
D Provides Reference Clock And Synthesized Clock
D 5 to 32 MHz Input Reference Frequency
D Pin-to-Pin Compatible to Avasem AV9107
D Programmable Analog Phase Locked Loop
June 1997-3
D Low Power Single 5V CMOS Technology
D Up to 16 Frequencies Stored Internally
D 8/14 pin DIP or SOIC Package
GENERAL DESCRIPTION
The ST49C107A-04 is a mask programmable monolithic
analog CMOS device designed to generate two
simultaneous clocks. The output frequency can vary from
2 to 130MHz, with up to 16 single selectable
preprogrammed frequencies stored in internal ROM.
The ST49C107A-04 is designed to replace existing CPU
mother board clocks generated from individual oscillators
in order to reduce board space and number of oscillators.
To provide high speed and low jitter clock, the parts utilize
a high speed analog CMOS phase locked loop using
14.318 MHz system clock as the reference clock (note
that reference clock can be changed to generate optional
frequencies from a standard programmed device). The
programmed clock outputs are selectable via four
address lines.
ORDERING INFORMATION
Part No.
ST49C107ACF14-04
Package
14 Lead 150 Mil JEDEC SOIC
Operating
Temperature Range
0°C to 70°C
BLOCK DIAGRAM
XTAL XTAL
Oscillator
Circuit
Programmable
Counter
B
Phase
Detector
Charge
Pump
Loop
Filter
Voltage
Controlled
Oscillator
Rom Table
Select
Logic
A0-A3
Programmable
Counter
A
Voltage
Reference
Circuit
Figure 1. Block Diagram
OE1 OE2
Output
Buffer
Programmable
Counter
C
1X-CLOCK
2X-CLOCK
B=5....128
A=5....128
C = 1, 2, 4
Rev. P2.00
E1996
EXAR Corporation, 48720 Kato Road, Fremont, CA 94538 z [phone] z FAX [phone]
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