19
Application Circuit
1 HPT
2 RD
3 DT
4 DR
5 TIPX
6 RINGX
7 BGND
8 VCC
9 RINGRLY
10 VBAT
11 RSG
HPR 22
VTX 21
VEE 20
RSN 19
AGND 18
RDC 17
C1 16
C2 15
DET 14
EO 13
E1 12
TIP
RING
VBAT
R3
RRT
R2
-5V
RD
RF1
RF2
CRC
CTC
RINGING
(VBAT + 90VRMS)
VBAT
CHP (NOTE 32)
-5V
RTX
RT
RB
RDC1
CDC
RDC2
RFB
CODEC/FILTER
U2
U1
RRX
-
+
CRT
R1
R4
NOTE 31
-5V
RSG
U1 SLIC (Subscriber Line Interface Circuit)
HC5513
U2 Combination CODEC/Filter e.g.
CD22354A or Programmable CODEC/
Filter, e.g. SLAC
CDC 1.5F, 20%, 10V
CHP 10nF, 20%, 100V (Note 2)
CRT 0.39F, 20%, 100V
CTC, CRC 2200pF, 20%, 100V
Relay Relay, 2C Contacts, 5V or 12V Coil
D1 - D5 IN4007 Diode
Surgector SGT27S10
PTC Polyswitch TR600-150
D6 Diode, 1N4454
RF1, RF2 Line Resistor, 20, 1% Match, 2 W
Carbon column resistor or thick film on
ceramic
R1, R3 200k, 5%, 1/4W
R2 910k, 5%, 1/4W
R4 1.2M, 5%, 1/4W
RB 18.7k,1%, 1/4W
RD 39k, 5%, 1/4W
RDC1, RDC2 41.2k, 5%, 1/4W
RFB 20.0k, 1%, 1/4W
RRX 280k, 1%, 1/4W
RT 562k, 1%, 1/4W
RTX 20k, 1%, 1/4W
RRT 150, 5%, 2W
RSG VBAT = -28V, RSG = ∞
VBAT = -48V, RSG = 21.4k, 1/4W 5%
NOTES:
31. It is recommended that the anodes of D3 and D4 be shorted to ground through a battery referenced surgector (SGT27S10).
32. To meet the specified 25dB 2-wire return loss at 200Hz, CHP needs to be 20nF, 20%, 100V.
FIGURE 21. APPLICATION CIRCUIT
+5V
RELAY
D6
OR
12V
PTC
Surgector
A
K
G
D3
D1
D2
D4
D5
HC5513