4-Level FSK Modem Data Pump
FX919A
Package
P4/D2/D5
Pin No.
20
21
Name
TXOP
V
BIAS
Signal
Description
Type
O/P
O/P
The Tx signal output from the modem.
A bias line for the internal circuitry, held at
�½ V
DD
. This pin must be decoupled to V
SS
by a
capacitor mounted close to the device pins.
The input to the Rx input amplifier.
The output of the Rx input amplifier and the input
to the Rx RRC filter.
The positive supply rail. Levels and voltages are
dependent upon this supply. This pin should be
decoupled to V
SS
by a capacitor.
22
23
RXIN
RXFB
I/P
O/P
24
V
DD
Power
Notes:
I/P =
O/P =
BI
=
Input
Output
Bidirectional
Internal protection diodes are connected from each signal pin to V
DD
and V
SS
.
©
1996 Consumer Microcircuits Limited
5
D/919A/4
CMLMICRO [ CML MICROCIRCUITS ]
