Lucent Technologies Inc.
9
Data Sheet
April 2000
L8560 Low-Power SLIC with Ringing
Functional Description
Table 3. Input State Coding
Table 4. Supervision Coding
B0
1
B1
1
B2
0
BR
1
State/Definition
Powerup, Forward Battery V
BAT2
.
Pin PT is positive with respect to pin PR. V
BAT2
is applied
to the tip/ring drive amplifiers. On-hook transmission capability. All supervision active—an
off-hook condition or a ring trip causes output NSTAT to go low.
Powerup, Reverse Battery V
BAT2
.
Pin PR is positive with respect to pin PT. V
BAT2
is applied
to the tip/ring drive amplifiers. On-hook transmission capability. All supervision active—an
off-hook condition or a ring trip causes output NSTAT to go low.
Powerup, Forward Battery V
BAT1
.
Pin PT is positive with respect to pin PR. V
BAT1
is applied
to the tip/ring drive amplifiers. On-hook transmission capability. All supervision active—an
off-hook condition or a ring trip causes output NSTAT to go low.
Powerup, Reverse Battery V
BAT1
.
Pin PR is positive with respect to pin PT. V
BAT1
is applied
to the tip/ring drive amplifiers. On-hook transmission capability. All supervision active—an
off-hook condition or a ring trip causes output NSTAT to go low.
Ground Start.
Tip drive amplifier is turned off. The device presents a high impedance
(>100 k
) to pin PT and a current-limited battery (V
BAT1
) to pin PR. Output pin RGDET indi-
cates current flowing in the ring lead.
Low-Power Scan.
Except for off-hook supervision, all circuits are shut down to conserve
power. Only the off-hook detector affects output pin NSTAT. V
BAT1
is applied to the tip/ring
drive amplifiers. Pin PT is positive with respect to pin PR. On-hook transmission is disabled.
Low-Power Scan (L8560D/E/F/G Only).
Except for off-hook supervision, all circuits are shut
down to conserve power. Only the off-hook detector affects output pin NSTAT. V
BAT2
is ap-
plied to the tip/ring drive amplifiers. Pin PT is positive with respect to pin PR. On-hook trans-
mission is disabled.
Forward Disconnect.
The tip and ring amplifiers are turned off and the SLIC goes into a
high-impedance state (>100 k
). V
BAT2
is applied to the SLIC.
Ring State.
SLIC is powered up. V
BAT1
is applied to the tip and ring amplifiers. Current limit
is increased by a factor of 2.8. Overhead voltage is reduced to approximately 2.4 V. These
conditions are necessary to supply sufficient power to drive a true North American 5 REN
ringing load (1386
+ 40
μ
F). Loop closure detector is disabled—only the ring trip detector
affects output pin NSTAT. To apply a balanced ring signal to pins PR and PT, apply a 0 V to
5 V square wave to input pin B1. Ringing frequency is the frequency of the input wave at B1.
To shape the ring signal at pins PR and PT, connect a capacitor from pin FB1 to ground and
from pin FB2 to ground.
1
0
0
1
1
1
1
1
1
0
1
1
0
1
1
1
0
0
1
1
0
1
0
1
0
0
0
1
1
1/0
1
0
Pin NSTAT
Pin RGDET
1 = ring ground
0 = no ring ground
0 = off-hook or ring trip
1 = on-hook and no ring trip