PBL386151 Ericsson, PBL386151 Datasheet - Page 16

• Manufacturer Part Number: PBL386151
• Description: Subscriber Line Interface Circuit
• Manufacturer: Ericsson

PBL 386 15/1
Control Inputs
The PBL 386 15/1 SLIC has three digital
control inputs, C1, C2 and C3.
A decoder in the SLIC interprets the control
input condition and sets up the command-
ed operating state.
C1 to C3 are internal pull-up inputs.
Open Circuit State
In the Open Circuit State the TIPX and
RINGX line drive amplifiers as well as other
circuit blocks are powered down. This caus-
es the SLIC to present a high impedance to
the line. Power dissipation is at a minimum
and no detectors are active.
Ringing State
In the ringing state the SLIC will behave as
in the active state with the exception that
the ring relay driver and the ring trip detec-
tor are activated. The ring trip detector will
indicate off hook with a logic low level at the
detector output.
Active State
TIPX is the terminal closest to ground and
sources loop current while RINGX is the
more negative terminal and sinks loop cur-
rent. The loop current or the ground key
detector is activated. The loop current de-
tector indicates off hook with a logic low
level and the ground key detector indicates
active ground key with a logic high level
present at the detector output.
16
Active Polarity Reversal State
TIPX and RINGX polarity is reversed com-
pared to the Active State: RINGX is the
terminal closest to ground and sources
loop current while TIPX is the more nega-
tive terminal and sinks current. The loop
current or the ground key detector is acti-
vated. The loop current detector will indi-
cate off hook with a logic low level and the
ground key detector will indicate active
ground key with a logic high level present at
the detector output.
The temperature guard indicates if an error
has occurred and the temperature guard is
activated. The output pin DET is forced to
a logic low level when activated .
Active Temperature guard state
Figure 16. Line voltage measurment
Line Voltage measurement
The line voltage is presented on the detec-
tor output as a pulse train (see figure 16)
with a frequency inversely proportional to
the voltage according to the equation:
started when entering this state from any
other state and the SLIC will be as in active
state except for the detector. The data can
be used in variety of ways, for example to
set transmission parameters in a program-
mable CODEC, in line testing where short
circuits on the line can be detected and to
control the metering signal amplitude.
freq =
The line voltage measurement will be
|V
10
TR
| + 1
6
[Hz]