ICS9120-46 Datasheet, PDF (2/5 Pages) Integrated Circuit Systems – Modem and Audio Clock Generator

ICS9120-46
Pin Configuration
8-Pin SOIC
Functionality
The ICS9120-46 incorporates a crystal oscillator circuit designed
to provide 50% duty cycle over a range of operating conditions,
including the addition of external crystal load capacitors to pins
X1 and X2.
For the crystal oscillator, the crystal load capacitance must be
connected externally by adding a capacitor from each of the X1
and X2 pins to ground. A parallel resonant 14.7456 MHz crystal is
recommended.
Duty cycle is also maintained when using an external clock source
(connected to X1, X2 left unconnected) as long as the external
clock has good duty cycle.
Functionality
X1 (MHz)
PD#
-
0
14.7456 1
CLK1
(MHz)
Low
49.92
CLK2
(MHz)
Low
40.32
REF
(MHa)
Low
14.7456
Pin Descriptions for ICS9120-46
PIN
NUM BER
1
2
3
4
5
6
7
8
PIN
NAM E
X1
VDD
GND
CLK1
PD#
CLK2
REF
X2
TYPE
Input
P o w er
P o w er
O u tpu t
O u tpu t
O u tpu t
O u tpu t
O u tpu t
DESCRIPTION
Crystal or external clock source. Has feedback bias for crystal.
Nominally 14.7456<N>MHz input applied. (No internal load cap;
m ust connect external load cap to ground for crystal oscillator.)
+Power supply input.
Ground return for Pin 2.
49.92 MH z target output clock
(with nominal 14.7456 MHz input).
Power-down input. A ll outputs shut off and driven to low output state
when this pin is at logic low level. Has pull-up.
40.32 MH z target output clock.
14.7456 M Hz reference clock buffered output
(with nominal 14.7456 MHz input).
Crystal output drive (leave this pin unconnected when using an
external clock). (No internal load cap; must connect external load cap
to ground for crystal oscillator).
2