V.22 bis Modem with AT Commands
CMX866
1.3
Signal List
CMX866
D1/D6
Pin No.
1
2
3
4
5
Signal
Name
XTALN
XTAL/CLOCK
N/C
N/C
RDRVN
Type
O/P
I/P
~
~
O/P
The output of the on-chip Xtal oscillator inverter.
The input to the oscillator inverter from the Xtal
circuit or external clock source.
Reserved for future use. Connect this pin to
DV
SS
.
Reserved for future use. Connect this pin to
DV
SS
.
Relay drive output, low resistance pull down to
DV
SS
when active and medium resistance pull
up to DV
DD
when inactive.
The negative supply rail for the digital on-chip
blocks.
Schmitt trigger input to the Ring signal detector.
Connect to DV
SS
if Ring Detector not used.
Open drain output and Schmitt trigger input
forming part of the Ring signal detector.
Connect to DV
DD
if Ring Detector not used.
Schmitt trigger input to an active-low reset pin.
Connect to DV
DD
if no external reset signal
used
The output of the Rx Input Amplifier.
An alternative, switched inverting input to the
Rx Input Amplifier, used to increase the
amplifier gain for the detection of on-hook
signals. If this input is not required, leave the
pin disconnected.
The inverting input to the Rx Input Amplifier
The non-inverting input to the Rx Input
Amplifier. If this pin is to be connected to V
BIAS
then it should also be decoupled to AV
SS
locally.
The negative supply rail for the analogue on-
chip blocks.
Internally generated bias voltage of
approximately AV
DD
/2, except when the device
is in Powersave or 'Zero-Power' modes, when
V
BIAS
will discharge to AV
SS
. This pin should be
decoupled to AV
SS
by a capacitor mounted
close to the device pins.
The inverted output of the Tx Output Buffer.
The non-inverted output of the Tx Output Buffer.
Description
6
7
8
DV
SS
RD
RT
Power
I/P
BI
9
RESETN
I/P
10
11
RXAFB
RXBN
O/P
I/P
12
13
RXAN
RXA
I/P
I/P
14
15
AV
SS
V
BIAS
Power
O/P
16
17
TXAN
TXA
O/P
O/P
©
2004 CML Microsystems Plc
4
D/866/4
CMLMICRO [ CML MICROCIRCUITS ]
