Preliminary Data Sheet
September 2001
L9216B/H
High-Voltage Ringing SLIC with Ground Start
Pin Information
(continued)
(continued)
Pin
17
Symbol
RGDET
Type
O
Name/Function
Ring Ground Detect.
When high, this open collector output indicates the pres-
ence of a ring ground or a tip ground. This supervision output may be used in
ground key, ground start or common-mode fault detection applications.
Common-Mode Current Sense.
To program tip or ring ground sense threshold,
connect a resistor to V
CC
and connect a capacitor to AGND to filter 50/60 Hz. If
unused, the pin is connected to ground.
Polarity Reversal Slowdown Capacitor.
Connect a capacitor from this node to
ground for controlling rate of battery reversal. If ramped battery reversal is not
desired, this pin is left open.
Polarity Reversal Slowdown Capacitor.
Connect a capacitor from this node to
ground for controlling rate of battery reversal. If ramped battery reversal is not
desired, this pin is left open.
Protected Tip.
The output drive of the tip amplifier and input to the loop-sensing
circuit. Connect to loop through overvoltage and overcurrent protection.
Protected Ring.
The output drive of the ring amplifier and input to the loop-sens-
ing circuit. Connect to loop through overvoltage and overcurrent protection.
State Control Input.
These pins have an internal 110 kΩ pull-down.
18
ICM
I
19
FB2
—
20
FB1
—
21
22
23
24
25
26
PT
PR
B2
B1
B0
ITR
I/O
I/O
I
d
I
d
I
d
I
Transmit Gain.
Input to AX amplifier. Connect a 4.75 kΩ resistor from this node to
VTX to set transmit gain. Gain shaping for termination impedance with a first-gen-
eration codec is also achieved with a network from this node to VTX.
ac Output Voltage.
Output of internal AX amplifier. The voltage at this pin is
directly proportional to the differential tip/ring current.
ac/dc Separation.
Input to internal AAC amplifier. Connect a 0.1
µF
capacitor
from this pin to VTX.
27
28
VTX
TXI
O
I
Operating States
Table 2. Control States
B0
1
1
1
1
0
0
0
0
B1
1
0
1
0
0
1
0
1
B2
0
0
1
1
1
1
0
0
State
Forward active
Reverse active
On-hook transmission forward battery
On-hook transmission reverse battery
Ground start
Scan
Disconnect, device will power up in this state
Ring
Table 3. Supervision Coding
NSTAT
0 = off-hook or ring trip or TSD.
1 = on-hook and no ring trip and no TSD or DISCONNECT state.
Agere Systems Inc.
RGDET
0 = no ring or tip ground.
1 = ring or tip ground.
9
ZARLINK [ ZARLINK SEMICONDUCTOR INC ]
