Highly integrated car-lock controller boosts safety

As a complete centralized solution for electronically driving car locks from a body-control module (BCM), the L99UDL01 replaces multiple individual motor drivers and associated analog and passive components while providing more sophisticated functionality.

The IC integrates a unique safety feature that overrides normal operation in the event of an accident to help ensure that first responders will have access to the vehicle. Adding further value are PWM output-current regulation and high-level diagnostics capable of detecting over current, open load, short to battery, and short to ground. The load-integrity checks can be completed without actuating the load.

The six integrated MOSFET half bridges can be connected independently or as two channels containing up to three half bridges in parallel to share higher-current loads. The output MOSFETs are fully protected and have low R_DS(ON) to boost energy efficiency and ease thermal management.

Key parameters are adjustable to ensure optimal performance, including the on-time duration, off-state fault detection, and output-current magnitude and direction. The programmable current limit lets designers lower stress on door-lock motors to enhance reliability.

The two half-bridge gate drivers enhance flexibility by allowing designers to connect their choice of N-channel MOSFETs or Smart Power devices to control additional high-powered loads. The drivers incorporate active recirculation that minimizes power dissipation. Protection for the external power devices is also built-in, including drain-source current monitoring and off-state fault detection.

In addition, the L99UDL01 has two power-saving modes including a 50µA standby mode ready for re-activation by an SPI command from the BCM and sleep mode that reduces current to below 15µA.

The L99UDL01 is in production now, packaged in 10mm x 10mm TQFP64L, and is available from $3.63 for orders of 1,000 pieces.