S E M I C O N D U C T O R
4-35
ADVANCE INFORMATION
January 1997
HC5521
SLIC
Subscriber Line Interface Circuit
Features
Normal and Reversed DC Feed
30mA Current Limit
Ringing, Test-In, and Test-Out Relay Drivers
Ground Key Detector with Seperate Logic Output
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
Applications
PABX/CO Line Circuits
Description
The HC5521 is a Monolithic Subscriber Line Interface Circuit
(SLIC) for Analog Subscriber Line cards in Central Office
and PABX switches.
The HC5521 provides a comprehensive set of features for
these applications including loop reversal, ground key detec-
tion, zero crossing ring relay operation, long loop drive and a
mutually independent setting of the receive and transmit
gains, and the two-wire impedance synthesis. An option is
also provided for eliminating transhybrid balance on-chip.
Advanced power management features combined with a
small 44 lead MQFP package allow significant board space
to be freed up for additional line circuits.
The HC5521 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.
HC5521CQ
0 to 70
44 Ld MQFP
Q44.10x10
HC5521CM
0 to 70
44 Ld PLCC
N44.65
TIP
TIPSEN
TEST
CONTROL
2-WIRE
INTERFACE
RING
CONTROL
AGND
BIAS
RINGSEN
RING
RX
RN
TX
TX4W
TA
TB
RBL
RBH
RD
CRTD
POWER
MANAGEMENT
RPSB
RPST
RPSG
RGND
BGND
V
CC
CDC
V
EE
CP
V
BAT
RDC
RPSR
BATTERY
REFERENCE
4-WIRE INTERFACE / Z
0
KZO
LOGIC
D6TAI
D3PDI
D4RCI
D2PRI
D5TBI
GKDO
SHDO
CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper IC Handling Procedures.
Copyright
Harris Corporation 1997
File Number
4265
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