Data Sheet
April 2000
L8560 Low-Power SLIC with Ringing
36
Lucent Technologies Inc.
Applications
(continued)
Design Considerations
(continued)
Table 12. Parts List for Loop Start with Bused Ringing and Ground Start Applications
(continued)
Name
Value
Function
ac Characteristics
R
GX
C
B2
R
T3
R
RCV
R
GP
C
GP
R
GP2
R
GN
C
C1
C
C2
R
T6
R
X
R
HB1
Supervision
R
LCTH
R
TS1
R
TS2
C
RTS1
C
RTS2
R
TSN
R
TSP
Ground Start
C
ICM
R
GDET
R
ICM2
4.32 k
, 1%, 1/8 W
0.1
μ
F, 20%, 10 V
174 k
, 1%, 1/8 W
100 k
, 1%, 1/8 W
41.2 k
, 1%, 1/8 W
220 pF, 20%, 10 V
1.21 k
, 1%, 1/8 W
29.4 k
, 1%, 1/8 W
0.1
μ
F, 20%, 10 V
0.1
μ
F, 20%, 10 V
49.9 k
, 1%, 1/8 W
75.0 k
, 1%, 1/8 W
75.0 k
, 1%, 1/8 W
Sets internal transmit path gain of 9.6.
ac/dc separation capacitor.
With R
GP
and R
RCV
, sets ac termination impedance.
With R
GP
and R
T3
, sets receive gain.
With R
T3
and R
RCV
, sets ac termination impedance and receive gain.
Loop stability.
Loop stability.
Compensates for input bias offset at RCVN/RCVP.
dc blocking capacitor.
dc blocking capacitor.
With R
X
, sets transmit gain in codec.
With R
T6
, sets transmit gain in codec.
Sets hybrid balance.
8.25 k
, 1%, 1/8 W
402
, 5%, 2 W
274 k
, 1%, 1/8 W
0.022
μ
F, 20%, 5 V
0.27
μ
F, 20%, 100 V
2 M
, 1%, 1/8 W
2 M
, 1%, 1/8 W
Sets loop closure (off-hook) threshold.
Ringing source series resistor.
With C
RTS2
, forms first pole of a double pole, 2 Hz ring trip sense filter.
With R
TSN
and R
TSP
, forms second 2 Hz filter pole.
With R
TS2
, forms first 2 Hz filter pole.
With C
RTS1
and R
TSP
, forms second 2 Hz filter pole.
With C
RTS1
and R
TSN
,
forms second 2 Hz filter pole.
0.47
μ
F, 20%, 10 V
100 k
, 20%, 1/8 W
71.5 k
, 1%, 1/8 W
Provides 60 Hz filtering for ring ground detection.
Digital output pull-up resistor.
Sets ring ground detection threshold.