SEMICONDUCT OR

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.

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

CDC

CP

RDC

RPSR

BATTERY

REFERENCE

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

File Number

4265