LUCL8576BP-D AGERE [Agere Systems], LUCL8576BP-D Datasheet - Page 9

• Manufacturer Part Number: LUCL8576BP-D
• Description: Dual Ringing SLIC
• Manufacturer: AGERE [Agere Systems]

May 2001
Agere Systems Inc.
Operating States
These states are selected using three logic inputs, B2, RNGNG, and NDISC. B2 sets normal operation, either with
forward or reverse battery. RNGNG overrides B2 and applies ringing with the polarity of tip and ring reversed on
edges of the B2 signal. The slope of the waveform is determined by a resistor from RRNG to AGND. Logic input
NDISC puts the device into a loop current denial state (disconnect). Tip and ring amplifiers are saturated against
ground with about a 100 A current source. This creates a level in the loop current sensing circuitry that
approaches a loop closed state. Some conditions on the tip and ring could cause the circuit to indicate loop closed
even though the loop is open. This situation can be prevented by connecting a 300 k
the outputs of the tip and ring amplifiers (see Figure 2). This will pull the amplifier output to about 30 V above V
keeping the NSTAT output at a steady high (on-hook indication) level. If the disconnect state is not used or the
NSTAT output during the disconnect state is not recognized or used, then the resistors are not needed.
Table 2 below summarizes the operating input state coding.
Table 2. Input State Coding
Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. These are abso-
lute stress ratings only. Functional operation of the device is not implied at these or any other conditions in excess
of those given in the operational sections of the data sheet. Exposure to absolute maximum ratings for extended
periods can adversely affect device reliability.
Note: The IC can be damaged unless all ground connections are applied before, and removed after, all other connections. Furthermore, when
5 V dc Supplies
Office Battery Supply
Logic Input Voltage
Logic Input Clamp Diode Current, per Pin
Logic Output Voltage
Logic Output Current, per Pin
Analog Input Voltage
Maximum Junction Temperature
Storage Temperature Range
Relative Humidity Range (noncondensing)
Ground Potential Difference (BGND to AGND)
PT or PR Fault Voltage (dc)
PT or PR Fault Voltage (10 µs x 1000 µs)
NDISC RNGNG B2
1
1
1
1
0
powering the device, the user must guarantee that no external potential creates a voltage on any pin of the device that exceeds its rat-
ings. For example, inductance in a supply lead could resonate with the supply filter capacitor to cause a destructive overvoltage.
0/1
0
0
1
1
Parameter
1
0
0/1 Disconnect State. The tip and ring amplifiers are turned off, and the SLIC goes into a
1
0
(continued)
Forward Battery, Normal Talk, and Feed State. Pin PT is positive with respect to PR.
Reverse Battery, Normal Talk, and Feed State. Pin PT is negative with respect to PR.
Ringing Is Applied to PT and PR. On the transition, PT starts towards a positive volt-
age (with respect to PR). The endpoint of this state is PT at BGND and PR at V
Ringing Is Applied to PT and PR. On the transition, PT starts towards a negative volt-
age (with respect to PR). The endpoint of this state is PT at V
high-impedance state (>100 k ).
(at T
A
= 25 C)
Symbol
V
V
T
—
—
—
—
—
—
—
—
—
—
BAT
stg
CC
V
V
BAT
BAT
–0.5
–0.5
–7.0
State
–0.5
Min
–75
–40
—
—
—
—
5
– 15
– 5
L8576B Dual Ringing SLIC
Typ
165
—
—
—
—
—
—
—
—
—
20
35
3
resistor from V
BAT
V
V
and PR at BGND.
CC
CC
Max
125
7.0
0.5
7.0
15
—
—
—
—
95
3
+ 0.5
+ 0.5
BAT
to each of
BAT
Unit
mA
mA
%
V
V
V
V
V
V
V
V
.
C
C
BAT
,
9