LUCL9312AP-D AGERE [Agere Systems], LUCL9312AP-D Datasheet - Page 34

• Manufacturer Part Number: LUCL9312AP-D
• Description: Line Interface and Line Access Circuit Forward Battery SLIC and Ringing Relay for TR-57 Applications
• Manufacturer: AGERE [Agere Systems]

Forward Battery SLIC and Ringing Relay for TR-57 Applications
ac Applications
First-Generation Codec ac Interface Net-
work: Resistive Termination
The following reference circuit shows the complete
SLIC schematic for interface to the Agere T7504 first-
generation codec for a resistive termination imped-
ance. For this example, the ac interface was designed
for a 600
with transmit gain and receive gain set to 0 dBm.
34
34
V
S
Z
T/R
Z
T
resistive termination and hybrid balance
+
–
I
V
T/R
R
R
T/R
P
P
RING
TIP
SWITCH
SWITCH
(continued)
BREAK
BREAK
18
18
CURRENT
SENSE
20
20
Figure 14. ac Equivalent Circuit
A
A
V
V
= 1
= –1
–0.300 V/mA
L9312
A
V
= 4
Also, this example illustrates the device with a single
battery operation, fixed current limit, and fixed loop clo-
sure threshold. This is a lower feature application
example.
Resistor R
match of input bias voltage at the RCVN/RCVP inputs.
If it is not used, there may be a slight offset at tip and
ring due to mismatch of input bias voltage at the
RCVN/RCVP inputs. It is very common to simply tie
RCVN directly to ground in this particular mode of oper-
ation. If used, to calculate R
RCVN to ac ground should equal the impedance from
RCVP to ac ground.
VITR
–
+
RCVN
V
RCVP
REF
GN
V
REF
is optional. It compensates for any mis-
R
R
GP
R
R
T3
RCV
T6
R
HB1
GN
, the impedance from
VFR
VF
VF
X
X
1/4 T7504 CODEC
IN
IP
Agere Systems Inc.
–
+
R
X
2.4 V
July 2001
12-3580 (F)
VGSX