LUCL9311AP-D AGERE [Agere Systems], LUCL9311AP-D Datasheet - Page 31

• Manufacturer Part Number: LUCL9311AP-D
• Description: Line Interface and Line Access Circuit Full-Feature SLIC with High Longitudinal Balance, Ringing Relay,and GR-909 Test Access
• Manufacturer: AGERE [Agere Systems]

July 2001
Applications
dc Characteristics
Overhead Voltage (continued)
In the scan mode, overhead is unaffected by V
internally fixed by the scan clamp circuitry to within the
specified limits.
The TESTSIG and RCV inputs will not overload with an
input signal swing between ground and V
However, the SLIC output saturation point (at PT/PR) is
a function of the device overhead. Default overhead
with OVH = 0 is 3.14 dBm into 900 . After that, output
signal swing increases 1 V for every volt that overhead
is increased.
Overhead voltage may need to be increased to accom-
modate on-hook transmission of higher-voltage sig-
nals.
The overhead is set with respect to battery voltage and
during a test mode, the battery voltage is unknown.
With zero voltage on RCV input, the output is battery
voltage minus the overhead on the input, which is the
main offset. The small RCV input offset that is multi-
plied by RCV gain to tip/ring output is inconsequential.
dc Loop Current Limit
In the active modes, dc current limit is programmable
via an applied voltage source at the device’s V
control input. The voltage source may be an external
voltage source or derived via a resistor divider network
from the V
source. A programmable external voltage source may
be used to provide software control of the loop current
limit. The loop current limit (I
voltage by:
I
Note that the overall current-limit accuracy achieved
will not only be affected by the specified accuracy of
the internal SLIC current-limit circuit (accuracy associ-
ated with the 50 term), but also by the accuracy of the
voltage source and the accuracy of any external resis-
tor divider network used and voltage offsets due to the
specified input bias current. If a resistor divider from
V
more accurate result due to a lower offset associated
with the input bias current; however, lower value resis-
tors will also draw more power from V
the two resistors in the resistor divider should be
between 75 k
accuracies are specified in Table 8 and Table 9.
Agere Systems Inc.
LIM
REF
(mA) = 50 x V
is used, a lower magnitude resistor will give a
REF
SLIC output or an external voltage
and 200 k . Offset at V
PROG
(continued)
(V)
(continued)
LIM
) is related to the V
REF
PROG
. The sum of
CC
– 0.5 V.
and V
PROG
OVH
PROG
REF
and
The previous equation describes the active mode
steady-state current-limit response. There will be a
transient response of the current-limit circuit (with the
device in the active mode) upon an on- to off-hook tran-
sition. Typical active mode transient current-limit
response is given in Table 17.
Table 17. Typical Active Mode On- to Off-Hook Tip/
The current limit with the SLIC set in an active mode
will be different from the current limit with the SLIC set
in the scan mode. This is due to differences in the scan
clamp circuit versus the active tip/ring drive amplifiers.
The scan mode current limit is fixed and is a function of
the internal design of the scan clamp circuit. The
steady-state scan mode current limit will be a typical
40 mA to 50 mA and may, over temperature and pro-
cess, vary typically from 30 mA to 110 mA. The scan
clamp current limit will typically settle to its steady-state
value within 300 ms.
Loop Range
The dc loop range is calculated using:
R
V
loop range. The loop resistance value where the device
automatically switches to V
Automatic Battery Switch section of this data sheet.
dc Loop Current:
dc Loop Current:
dc Loop Current:
BAT1
L
Active Mode
R
Active Mode
R
Active Mode
R
=
Ringing Relay, and GR-909 Test Access
LOOP
Transition t < 5 ms
LOOP
Transition t < 50 ms
LOOP
Transition t < 300 ms
is used because we are calculating the maximum
----------------------------------
V
= 100
= 100
= 100
BAT
Ring Current-Limit Transient Response
I
LOOP
Parameter
–
V
OH
On- to Off-hook
On- to Off-hook
On- to Off-hook
– 2R
P
BAT2
– R
dc
is calculated in the
I
I
LIM
LIM
Value
I
LIM
+ 60
+ 20
Unit
mA
mA
mA
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