Data Sheet
July 2001
Full-Feature SLIC, Ringing Relay, and Test Access Device
L9310 Line Interface and Line Access Circuit
Agere Systems Inc.
13
Pin Information
(continued)
Table 1. Pin Descriptions
(continued)
Pin
37
Symbol
ITR
Type
I
Name/Function
Transmit Gain.
A current output which is proportional to the differential current
flowing from tip to ring. Input to AX amplifier. Connect a resistor from this node to
VTX to set transmit gain to 300
. Hybrid reject of meter pulse is done by a resis-
tor from this node to PPMOUT. Gain shaping for termination impedance with a
COMBO I codec is also achieved with a network from this node to VTX.
Transmit ac Input (Inverting).
For higher-voltage meter pulse signals (5 Vrms),
connect a network to this node for meter pulse filtering. If lower-voltage meter
pulse is used and meter pulse rejection is done via PPMOUT, this node is not
used. This node has an internal connection to V
REF
; thus, it may be left floating if
unused.
Transmit ac Input (Noninverting).
Connect a 0.1
μ
F capacitor from this pin to
VTX for dc blocking.
Transmit ac Output Voltage.
The output is a voltage that is directly proportional
to the differential ac tip/ring current. This output is connected via a proper inter-
face network to the codec.
Receive ac Signal Input (Noninverting).
This high-impedance input controls
the ac differential voltage on tip and ring.
Receive ac Signal Input (Inverting).
This high-impedance input controls the ac
differential voltage on tip and ring.
Analog Ground.
Ground return for V
CC
current.
5 V Analog Power Supply.
5 V supply for analog circuitry.
38
TXN
I
39
TXI
I
40
VITR
O
41
RCVP
I
42
RCVN
I
43
44
AGND
V
CC
G
P