L9217A Datasheet, PDF (17/30 Pages) Agere Systems – Low-Cost Line Interface with Reverse Battery and PPM

Data Sheet
November 2001
L9217A/G Low-Cost Line Interface
with Reverse Battery and PPM
Applications (continued)
A basic loop start reference circuit, using bused ringing with the L9217 SLIC and the T8536 third-generation codec,
is shown in Figure 12.
TIP
EMR
LCAS
RING
RTS1
510 Ω
VRING
RPROG
35.7 kΩ
RLCTH
22.1 kΩ
VCC _CCC
0.1 µF
14
IPROG VCC
7
LCTH
VBAT CBAT
0.1 µF
PPMIN
RFLT*
CPPM
0.01 µF
9
OPEN 21
28
VBAT
PPMIN PPMOUT
TG
ROVH
61.9 kΩ
8
DCOUT
27 _{OVH (for 3.5 Vrms PPM)}
VTX
TXI
RPT
50 Ω
18
PT
L7591
L9217
SLIC
VITR
RCVP
RCVN
RPR
50 Ω
RTSP
2.94 MΩ
CRTS1
0.015 µF
RTSN
3.4 MΩ
10 _PR
20 _RTSP
19
RTSN
CF2
CF1
11
12
CF1
0.47 µF
NSTAT
B0
B1
B2
AGND BGND
16 17
CHY
4.7 nF
RPPM
6.19 kΩ
26
RGP1
25
8.06 kΩ
CB
24
0.1 µF
RCIN
23
20 MΩ
5 ^{CB1 0.1 µF}
6
22
15
14
13
VBAT
CF2
0.1 µF
* Placeholder for potential resistor to form filter against PPM generator noise if necessary.
1/4 T8536 ^DX1
CODEC ^DX2
VFXI
DR1
VFROP
DR2
PCM
HIGHWAY
VFRON
SLIC0a
SLIC3a
SLIC2a
SLIC4a
FS
BCLK
VDD
CONTROL
AND
CLOCK
CVDD
0.1 µF
DGND
2798 (F)
Figure 12. Basic Loop Start Application Circuit Using T8536-Type Codec
Agere Systems Inc.
17