PBL 386 30/2
15
NU
Pin Not Used. Must be connected to AGND.
16
17
C2
C1
C1 and C2 are digital inputs (internal pull-up) controlling the SLIC operating states.
Refer to section "Operating states" for details.
18
19
20
21
DET
NC
Detector output. Active low when indicating loop detection and ring trip.
No internal Connection
VCC
PLD
+5 V power supply.
Programmable Loop Detector threshold. The loop detection threshold is programmed by a resistor
connected from this pin to AGND.
22
23
POV
PLC
Programmable Overhead Voltage. If pin is left open: The overhead voltage is internally set to min 2.7 V in
off-hook and min 1.1 V in On-hook. If a resistor is connected between this pin and AGND: the overhead
voltage can be set to higher values.
Prog. Line Current, the current limit, reference C in figure 12, is programmed by a resistor connected from
this pin to AGND.
24
25
26
REF
NC
A Reference, 49.9 kΩ, resistor should be connected from this pin to AGND.
No internal Connection
RSN
Receive Summing Node. 200 times the AC-current flowing into this pin equals the metallic (transversal)
AC-current flowing from RINGX to TIPX. Programming networks for two-wire impedance and receive gain
connect to the receive summing node. A resistor should be connected from this pin to AGND.
27
28
AGND
VTX
Analog Ground, should be tied together with BGND.
Transmit vf output. The AC voltage difference between TIPX and RINGX, the AC metallic voltage, is
reproduced as an unbalanced GND referenced signal at VTX with a gain of one (or one half, see pin PTG).
The two-wire impedance programming network connects between VTX and RSN.
SLIC Operating States
State
C2
C1
SLIC operating state
Active detector
0
1
2
3
0
0
1
1
0
1
0
1
Open circuit
Ringing state
Active state
Not applicable
-
Ring trip detector (active low)
Loop detector (active low)
-
Table 1. SLIC operating states.
9
ERICSSON [ ERICSSON ]
