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S E M I C O N D U C T O R
1
April 1997
HC5520
CO/PABX Polarity Reversal
Subscriber Line Interface Circuit
Features
Normal and Reversed DC Feed
Current Limited Loop Feed
Ringing, Test-In, and Test-Out Relay Drivers
Thermal Shutdown Protection with Alert Signal
On-Hook Transmission
Selectable Transmit and Receive Gain Setting
Selectable 2-Wire Impedance Matching
Zero Crossing Ring Trip Detection and Ring Relay
Release
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
Applications
CO/PABX Line Circuits
Description
The HC5520 is a Monolithic Subscriber Line Interface Circuit
(SLIC) for Analog Subscriber Line cards in Central Office
and PABX switches.
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.
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.
Block Diagram
Ordering Information
PART NUMBER
TEMP.
RANGE (
o
C)
PACKAGE
PKG. NO.
HC5520CQ
0 to 70
44 Ld MQFP
Q44.10x10
HC5520CM
0 to 70
44 Ld PLCC
N44.65
TIP
TIPSEN
TEST
CONTROL
2-WIRE
INTERFACE
RING
CONTROL
AGND
BIAS
RINGSEN
RING
R
X
R
N
T
X
T
X4W
TA
TB
R
BL
C
RTD
R
BH
RD
POWER
MANAGEMENT
R
PSB
R
PSR
R
PST
R
PSG
RGND
BGND
V
CC
V
EE
C
DC
C
P
V
BAT
R
DC
BATTERY
REFERENCE
4-WIRE INTERFACE / Z
0
K
ZO
LOGIC
TAI
PDI
RCI
PRI
TBI
TSDO
SHDO
HC5520
CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper IC Handling Procedures.
Copyright
Harris Corporation 1997
File Number
4148.2