S E M I C O N D U C T O R
HC5520
CO/PABX Polarity Reversal
Subscriber Line Interface Circuit
April 1997
Features
Description
• Normal and Reversed DC Feed
The HC5520 is a Monolithic Subscriber Line Interface Circuit
(SLIC) for Analog Subscriber Line cards in Central Office
and PABX switches.
• Current Limited Loop Feed
• Ringing, Test-In, and Test-Out Relay Drivers
• Thermal Shutdown Protection with Alert Signal
• On-Hook Transmission
The HC5520 provides a comprehensive set of features for
these applications including loop reversal, zero crossing
ringing relay operation, long loop drive and a mutually inde-
pendent setting of the receive and transmit gains, and the
two wire impedance synthesis. Advanced power manage-
ment features combined with a small 44 lead MQFP pack-
age allow significant board space to be freed up for
additional line circuits.
• Selectable Transmit and Receive Gain Setting
• Selectable 2-Wire Impedance Matching
• Zero Crossing Ring Trip Detection and Ring Relay
Release
The HC5520 is fabricated in a Harris state-of-the-art Bonded
Wafer High Voltage process, providing freedom from tradi-
tional JI latch-up phenomena without the use of additional
power supply filtering components or substrate tie connec-
tions. The very low parasitics and leakages associated with
this process provide an exceptionally flat performance over
frequency and temperature.
• Parallel Digital Control and Status Monitoring
• Protection Resistors Inside Feedback Loop Allows the
Use of PTC Devices Without Impact on Longitudinal
Balance
• Thermal Management Features
Ordering Information
TEMP.
o
Applications
PART NUMBER RANGE ( C)
PACKAGE
44 Ld MQFP
44 Ld PLCC
PKG. NO.
Q44.10x10
N44.65
• CO/PABX Line Circuits
HC5520CQ
HC5520CM
0 to 70
0 to 70
Block Diagram
R
T
T
R
K
ZO
X
X
X4W
N
TA
TEST CONTROL
TB
4-WIRE INTERFACE / Z
0
TSDO
HC5520
TIP
SHDO
PRI
TIPSEN
RINGSEN
RING
2-WIRE
INTERFACE
LOGIC
PDI
RCI
TBI
RD
TAI
R
RING
BH
CONTROL
R
BL
AGND
BGND
RGND
C
RTD
BATTERY
REFERENCE
R
R
R
R
BIAS
PSB
PSR
PST
PSG
V
BAT
POWER
MANAGEMENT
V
CC
V
EE
C
R
C
DC
P
DC
CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper IC Handling Procedures.
File Number 4148.2
Copyright © Harris Corporation 1997
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