Highly integrated universal door lock controller simplifies design and improves safety

     The STMicroelectronics L99UDL01 Universal door lock IC integrates six MOSFET half-bridge outputs and two half-bridge gate drivers, as well as circuit protection and diagnostic functions to improve solution security, simplify design, and save space.the L99UDL01 is a total solution that uses electronic technology to control vehicle locks from the body control module (BCM), replacing multiple independent motor drives and associated analog and passive devices while providing more advanced features.

     The IC integrates a unique safety protection function that forces normal operations to be taken over in the event of an accident, allowing emergency personnel to access the vehicle. Additional value-added features include PWM output current regulation and advanced diagnostics that detect overload current, open load, battery short and ground short circuits to complete load integrity checks without starting the load.

     The six MOSFET half-bridges integrated on the chip can be connected independently or combined into two output channels of up to three half-bridges each to distribute a larger current load. The output MOSFETs are fully protected and low RDS (ON) resistance improves energy efficiency and simplifies thermal management design. To ensure optimal performance, important parameters are adjustable, including on-time, off-state fault detection, and output current size and direction. With the settable current limiting function, designers can reduce the electrical stress on the lock motor, thereby improving system reliability.

     Two half-bridge gate drivers allow designers to connect the N-channel MOSFETs of their choice, or to control additional high-power loads, they can optionally connect smart power devices for increased design flexibility. The driver integrates an active current recirculation mode to minimize dissipated power, as well as built-in external power device protection, including drain-source current monitoring and off-state fault detection.

     In addition, the L99UDL01 has two power-saving modes, 50µA standby and sleep. The standby mode reactivates the controller via the SPI command of the BCM module, while the sleep mode reduces the current to less than 15µA.