hc5517b Intersil Corporation, hc5517b Datasheet - Page 9

• Manufacturer Part Number: hc5517b
• Description: Low Cost 3 Ren Ringing Slic For Isdn Modem/ta And Wl
• Manufacturer: Intersil Corporation

Pin Descriptions
PLCC
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
1
2
3
4
5
6
7
8
9
RING SENSE 1
RING SENSE 2
TIP SENSE
SYMBOL
AGND
BGND
V
I
OUT1
V
V
SHD
RDO
V
RTD
ALM
LIMIT
TST
-IN1
V
V
RDI
RING
RTI
RS
NU
NU
TF
RF
REF
F1
F0
BAT
CC
RX
TX
An analog input connected to the RING (more negative) side of the subscriber loop through a feed resistor. Functions
The inverting input of the impedance matching amplifier. The non-inverting input is internally connected to AGND.
Analog Ground - Serves as a reference for the transmit output and receive input terminals.
Positive Voltage Source - normally +5V DC.
An external voltage connected to this pin will override the internal V
Power Denial - An active low TTL compatible logic control input. When enabled, the output of the ring amplifier will
ramp close to the output voltage of the tip amplifier.
TTL compatible logic control input that controls multiplexing of the detector outputs.
TTL compatible logic control input that must be tied high for proper SLIC operation.
Switch Hook Detection - An active low TTL compatible logic output. Indicates an off-hook condition.
Ring Trip Detection - An active low TTL compatible logic output. Indicates an off-hook condition when the phone is
ringing. May be used to indicate ring trip or ground key detection.
A TTL logic input. A low on this pin will keep the SLIC in a power down mode. The TST pin, in conjunction with the
ALM pin, can provide thermal shutdown protection for the SLIC. Thermal shutdown is implemented by a system
controller that monitors the ALM pin. When the ALM pin is active (low), the system controller issues a command to
the TST pin (low) to power down the SLIC. The timing of the thermal recovery is controlled by the system controller.
A TTL compatible active low output which responds to the thermal detector circuit when a safe operating die
temperature has been exceeded.
Loop Current Limit - used with V
The 4-wire output of the SLIC.
An analog input connected to the TIP (more positive) side of the subscriber loop through a feed resistor. Functions
with the RING terminal to receive voice signals and for loop monitoring purpose.
with the TIP terminal to receive voice signals and for loop monitoring purposes.
This is an internal sense mode that must be tied to RING SENSE 1 for proper SLIC operation. Also used during
unbalanced ringing.
Receive Input, 4-Wire Side - A high impedance analog input. AC signals appearing at this input drive the Tip Feed
and Ring Feed amplifiers differentially.
Not used in this application. This pin should be left floating.
A low impedance analog voltage output which is proportional to the subscriber loop current. Since the DC level of
this output varies with loop current, capacitive coupling to IN1- is necessary.
TTL compatible input to drive the ring relay driver during unbalanced ringing.
Open collector relay driver used during unbalanced ringing.
Battery Ground - All loop current and some quiescent current flows from this terminal.
Not used in this application. This pin should be either grounded or left floating.
Low level ringing signal input.
Output of the tip line feed amplifier.
Output of the ring line feed amplifier.
The negative battery source, all loop current flows into this terminal.
Ring Trip Input - This pin is connected to the external negative peak detector output for ring trip detection.
69
TX
HC5517B
to set the short loop current limiting conditions.
DESCRIPTION
BAT
/2 reference.