T8531TLDB Agere Systems, Inc., T8531TLDB Datasheet - Page 43

• Manufacturer Part Number: T8531TLDB
• Description: CODEC, AMuLaw CODEC, Line Card Signal Processor for CODEC Chip Set, 64TQFP
• Manufacturer: Agere Systems, Inc.

February 2002
Agere Systems Inc.
Applications
Figure 12 shows the complete SLIC schematic for interfacing to the Agere L9215G short-loop, sine wave, ringing
SLIC. All ac parameters are programmed by the codec. Note this codec differentiates itself in that no external com-
ponents are required in the ac interface to provide a dc termination impedance or for stability. For illustration pur-
poses, 0.5 Vrms PPM injection was assumed in this example and no meter pulse rejection is used. Also, this
example illustrates the device using programmable overhead and current limit. The components associated with
V
REF
PROGRAMMABLE
can be replaced by a common voltage reference circuit (see Figure 14).
FUSIBLE OR PTC
FUSIBLE OR PTC
V
D/A VOLTAGE
BAT2
50
SOURCE
50
FROM
AGERE
L7591
0.1 F
C
383
RT
(continued)
R
k
RT
D
BAT1
CF1
RTFLT
DCOUT
PR
PT
OVH
V
V
V
V
PROG
REF
BAT1
BAT1
0.47 F
C
0.1 F
C
Figure 12. Line Card Solution Using the L9215G SLIC
F1
BAT1
BGND
CF2
C
0.1 F
0.1 F
C
F2
BAT2
rate of battery
reversal not
FB1 FB2
V
V
ramped
BAT2
BAT2
V
V
CC
CC
0.1 F
C
NSTAT BR B2 B1 B0
CC
L9215G
AGND ICM TRGDET
CONTROL
FROM/TO
ground key
not used
RING
C
0.47 F
IN
RING
PPM
used
not
VITR
R
R
VTX
CVN
ITR
CVP
TXI
IN
C
10 nF
PPM
0.5 Vrms
PPM
0.1 F
C
R
4750
C1
C
0.1 F
GX
TX
301 k
R
VREF3
V
Codec Chip Set
CC
VRTX
VTX
VRP
VRN
R
4.02 k
R
4.32 k
VREF1
VREF2
T8532
12-3534 (F).c
C
10 F
10 V
VREF
43