PBL 387 73
BW
BW
BW
HP
BGND
RINGX
TIPX
VTBAT
VBAT
VTB
LP
NC
BW
BW
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
VTX
RSN
AGND
VR
DET
C1
C2
C3
VCC
PLD
PRT
PLC
REF
CRING
28-pin SOIC
22
21
20
19
18
17
16
15
Figure 7. Pin configuration 28L-SOIC, top view.
Pin Description
Pin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Symbol
BW
BW
BW
HP
BGND
RINGX
TIPX
VTBAT
VBAT
VTB
LP
NC
BW
BW
CRING
REF
PLC
Description
Batwing
(refer to Note, Pin Description)
Batwing
(refer to Note, Pin Description)
Batwing
(refer to Note, Pin Description)
High Pass
AC/DC separation capacitor C
HP
connects between this pin and TIPX.
Battery Ground.
Shall be tied together with AGND.
The RINGX pin connects to the ring lead of the two-wire interface via over voltage protection components
(and optional test access switch).
The TIPX pin connects to the tip lead of the two-wire interface via over voltage protection components
(and optional test access switch).
Talk Battery.
The dc loop current is supplied to TIPX and RINGX from this battery voltage. Negative with respect to BGND.
On-hook Ringing Battery supply voltage. Negative with respect to BGND.
Internal SLIC bias voltage. Connected to the talk battery supply. Refer to the application diagram in figure 8.
May be connected to any voltage between -32 and –10 V.
Low Pass
saturation guard filter capacitor C
LP
connects between this pin and VTBAT to filter out noise and improve PSRR.
No Connect.
Batwing
(refer to Note, Pin Description)
Batwing
(refer to Note, Pin Description)
The capacitor C
RING
connects between this pin and AGND. Required for the ring signal generation.
A 15 kΩ resistor connected between this pin and AGND sets an internal SLIC reference current.
The value must not be changed.
Programmable Line Current.
The constant current DC feed is programmed by a resistor connected from this pin to AGND.
8
EN/LZT 146 137 R1A © Ericsson Microelectronics, December 2001
ERICSSON [ ERICSSON ]
