Document Number: 83832

www.vishay.com

Rev. 1.4, 11-Mar-11

1

This datasheet is subject to change without notice.

1 Form A Photo Darlington Telecom Switch

LH1539AAC, LH1539AACTR, LH1539AB

Vishay Semiconductors

DESCRIPTION

The LH1539 telecom switch consists of an optically isolated

solid state relay (SSR) form A and a bidirectional input

optocoupler in a single 8-pin package. The SSR is ideal for

switch hook and dial-pulse switching while the optocoupler

performs ring detect and loop current sensing functions.

input-to-output isolation voltage.

The SSR is integrated on a monolithic receptor die using

smart power technology. The SSR features low On

resistance, high breakdown voltage, and current-limit

circuitry that protects the relay from telephone line induced

lightning surges.

The optocoupler provides bidirectional current sensing via

two anti parallel GaAs infrared emitting diodes. Very high

current transfer ratio (CTR) is achieved by coupling to a

photodarlington transistor. This high CTR allows the user to

minimize the size of the ring detector capacitor.

FEATURES

• Solid state relay and autopolarity optocoupler

in one 8-pin package

• Surface mountable

• Optocoupler

- Bidirectional current detection

- High CTR:

 300 %

• Solid state relay

- Form A LH1525 type

- Low operating current

- Load voltage 400 V

- Load current 120 mA

- Current limit protection

- Linear, AC/DC operation

- Clean bounce free switching

- Low power consumption

• Compliant

to

RoHS

Directive

2002/95/EC

and

in

accordance to WEEE 2002/96/EC

APPLICATIONS

• General telecom switching

- On/off hook switching

- Dial pulse

- Ring current detection

- Loop current sensing

i179055-1

8

6

1

3

7

5

2

4

i179034_2

DIP

SMD

AGENCY APPROVALS

UL1577:

file no. E52744 system code H, double

protection

CSA:

certification no. 093751

BSI/BABT: certification no. 7980

ORDERING INFORMATION

L

H

1539

A

#

#

T

R

PART NUMBER

ELECTR.

VARIATION

PACKAGE

CONFIG.

TAPE AND

REEL

PACKAGE

UL, CSA, BSI

SMD-8, gullwing, tubes

LH1539AAC

SMD-8, gullwing, tape and reel

LH1539AACTR

DIP-8, tubes

LH1539AB

> 0.1 mm

7.62 mm

DIP

SMD