THBT15011_08 Datasheet, PDF (7/10 Pages) STMicroelectronics – Tripolar overvoltage protection for telecom line

THBT15011, THBT20011, THBT27011
2.1
Application circuits
Figure 9. Line card protection
RING
GENERATOR
Application information
- V_BAT
LINE A
T
E
S
T
R
E
L
A
Y
S
LINE B
PTC
THBTxxxD
PTC
RING
RELAY
LCP1521S
Figure 10. Protection for telephone set with ground key
Hook
LA
SLIC
220
nF
Speech
dialing
ringer
LB
THBTxxxD
Ground key
E
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