pbl386102qnt ETC-unknow, pbl386102qnt Datasheet - Page 14

• Manufacturer Part Number: pbl386102qnt
• Description: Subscriber Line Interface Circuit
• Manufacturer: ETC-unknow

PBL 386 10/2
Loop Current Detector
The loop current detector indicates that the
telephone is off hook and that DC current is
flowing in the loop by putting the output pin
DET, to a logic low level when selected.
The loop current detector threshold value,
I
es state, is programmable with the R
resistor. R
and ground and is calculated according to:
14
Figure 12. Single-channel subscriber line interface with PBL 386 10/2 and combination CODEC/filter
LTh
R
+12 V /+5V
, where the loop current detector chang-
LD
RESISTORS: (Values according to IEC-63 E96
series)
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
RING
TIP
SG
LD
LC
REF
T
TX
B
RX
FB
1
2
3
4
RT
RF
F1
=
, R
VB2
500
VB
I
LTh
F2
LD
KR
connects between pin PLD
E
RG
D
= 23.7 k
= 49.9 k
= 18.7 k
= 15 k
= 105 k
= 32.4k
= 57.6k
= 105k
Depending on CODEC / filter
= 604 k
= 604 k
= 249 k
= 280 k
= 332
= 332
= Line resistor, 40
B
R
RF
R
R
R
RT
1%
1%
1%
1%
1%
1%
1%
1%
1%
1%
1%
1%
5% 2 W
5% 2 W
F2
F1
D
BB
1
1
1
1
1
1
1
1
1
1
1
1
/
/
/
/
/
/
/
/
/
/
/
/
10
10
10
10
10
10
10
10
10
10
10
10
1%
W
W
W
W
W
W
W
W
W
W
W
W
D
C
OVP
B2
GG
R
R
1
2
LD
VB
and is not influenced by the ac signal at the
two wire side.
Ground Key Detector
The ground key detector indicates when
the ground key is pressed (active) by putting
the output pin DET to a logic high level
when selected. The ground key detector
circuit senses the difference between TIPX
and RINGX currents. The detector is trig-
gered when the difference exceeds the
current threshold.
CAPACITORS:(Values according to IEC-63 E6
series)
C
C
C
C
C
C
C
C
C
C
C
*100V if VEE pin connected to VBAT, VBAT2
The current detector is internally filtered
B
B2
VCC
VEE
TC
RC
HP
LP
GG
1
2
C
C
B2
B
C
1
C
C
RC
TC
R
3
= 100 nF
= 150 nF
= 100 nF
= 100 nF
= optional
= optional
= 68 nF
= 330 nF
= 220 nF
= 330 nF
= 330 nF
R
4
C
C
HP
LP
R
SG
C
2
100 V 20%
100 V 20%
100 V 20%
100 V 20%
100 V 20%
10 V 20%
10 V* 20%
63 V 10%
63 V 10%
PBL 386 10/2
RRLY
NC
HP
RINGX
BGND
TIPX
VBAT
VBAT2
AOV
PSG
DR
TS
LP
DT
AGND
RSN
DET
VCC
REF
VEE
VTX
PLD
PLC
NC
NC
C1
C2
C3
VCC
VEE
Ring Trip Detector
Ring trip detection is accomplished by con-
necting an external network to a compara-
tor in the SLIC with inputs DT and DR. The
ringing source can be balanced or unbal-
anced e g superimposed on the battery
voltage or ground. The unbalanced ringing
source may be applied to either the ring
lead or the tip lead with return via the other
wire. A ring relay driven by the SLIC ring
relay driver connects the ringing source to
tip and ring.
ity change at the comparator input when
DIODES:
D
D
D
OVP:
Secondary protection (eg Power Innovations TISP
PBL1 or PBL2). The ground terminals of the
secondary protection should be connected to the
common ground on the Printed Board Assembly
with a track as short and wide as possible,
preferably a groundplane.
The ring trip function is based on a polar-
B
B2
BB
R
R
R
LD
LC
REF
R
T
VBAT<VEE<-5 V
= 1N4448
= 1N4448
= 1N4448 (optional)
R
R
RX
TX
SYSTEM CONTROL
+5 V
INTERFACE
R
B
C
C
VEE
VCC
R
-
+
out
CODEC/
FB
Filter
VCC
VEE
out