HC5509A1R3060 Datasheet, PDF (5/10 Pages) Intersil Corporation – SLIC Subscriber Line Interface Circuit

HC5509A1R3060
Pin Descriptions
SOIC
SYMBOL
1
AG
2
VB+
3
C1
4
PD
5
RC
6
RS
7
SHD
8
GKD
9
TST
10
ALM
11
ILMT
12
OUT1
13
-IN1
14
TIP
15
RING
16
RFS
17
VRX
18
LAO
DESCRIPTION
Analog Ground - To be connected to zero potential. Serves as a reference for the transmit output and re-
ceive input terminals.
Positive Voltage Source - Most Positive Supply.
Capacitor #C1 - An external capacitor to be connected between this terminal and analog ground. Required
for proper operation of the loop current limiting function.
Power Denial - A low active TTL-compatible logic input. When enabled, the output of the ring amplifier will
ramp to close to the output voltage of the tip amplifier.
Ring Command - A low active TTL-compatible logic input. When enabled, the relay driver (RD) output goes
low on the next high level of the ring sync (RS) input, as long as the SLIC is not in the power down mode
(TST = 0) or the subscriber is not already off-hook (SHD = 0).
Ring Synchronization Input - A TTL - compatible clock input. The clock is arranged such that a positive
pulse (50 - 500µs) occurs on the zero crossing of the ring voltage source, as it appears at the RFS terminal.
For Tip side injected systems, the RS pulse should occur on the negative going zero crossing and for Ring
injected systems, on the positive going zero crossing. This ensures that the ring relay activates and deac-
tivates when the instantaneous ring voltage is near zero. If synchronization is not required, the pin should
be tied to +5.
Switch Hook Detection - An active low LS TTL compatible logic output. A line supervisory output.
Ground Key Detection - An active low LS TTL compatible logic output. A line supervisory output.
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 Test pin (low) to power down the SLIC. The timing of the thermal recovery is con-
trolled 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. Reference the TST pin description for a method to reduce prolonged
thermal overstress that may reduce component life.
Loop Current Limit - Voltage on this pin sets the short loop current limiting conditions using a resistive volt-
age divider.
The analog output of the spare operational amplifier.
The inverting analog input of the spare operational amplifier.
An analog input connected to the TIP (more positive) side of the subscriber loop through a feed resistor
and ring relay contact. Functions with the RING terminal to receive voice signals from the telephone and
for loop monitoring purpose.
An analog input connected to the RING (more negative) side of the subscriber loop through a feed resistor.
Functions with the TIP terminal to receive voice signals from the telephone and for loop monitoring purposes.
Ring Feed Sense - Senses RING side of the loop for Ground Key Detection. During Ring injected ringing
the ring signal at this node is isolated from RF via the ring relay. For Tip injected ringing, the RF and RFS
pins must be shorted.
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.
Longitudinal Amplifier Output - A low impedance output to be connected to C2 through a low pass filter.
Output is proportional to the difference in I_TIP and I_RING.
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