U6809B

• Digital Self-supervising Watchdog with Hysteresis
• Three 250-mA Output Drivers
• One Relay Driver, Two Lamp Drivers
• Lamp Drivers with Auxiliary Ground
• Lamp Drivers Short-circuit Protected
• Lamp Drivers with Status Feedback
• Enable Output
• Over-/Undervoltage Detection and Reset
• All Power Outputs Protected Against Standard Transients
• All Power Outputs Protected Against 40-V Load Dump
• Automatically Activated Lamp Drivers if V_S is Disconnected
• Automatically Activated Lamp Drivers Via AUX GND if Standard Ground is Disconnected

Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

The U6809B is designed to support the fail-safe function of safety-critical systems such as ABS. U6809B 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.