Rev. 4764A–AUTO–10/03

Features

Ground is Disconnected

Description

The U6809B is designed to support the fail-safe function of safety-critical systems

such as ABS. It includes a relay driver, two independent short-circuit-protected lamp

drivers which are supplied by redundant ground lines, two monitoring circuits for the

lamp driver output voltage and output current, a watchdog controlled by an external

RC network and a reset circuit initiated by an over- and undervoltage condition of the

5-V supply providing a positive and a negative reset signal.

Fail-safe IC with

Relay Driver

and Lamp

Driver

U6809B