With increasing demand for animation in automotive lighting, LEDs must be controlled independently. Therefore, LED drivers with digital interfaces are essential to effectively drive pixel-controlled lighting applications. In exterior lighting, multiple lamp functions are typically located on different PCB boards with off-board wires connected to each other. It is difficult for a traditional single-ended interface to meet the strict EMC requirements. By using an industrial-standard CAN physical layer, the UART-based FlexWire interface of the TPS929121-Q1 easily accomplishes long distance off-board communication without impacting EMC.
The TPS929121-Q1 is a 12-channel, 40-V high-side LED driver that controls the 8-bit output current and 12-bit PWM duty cycles. The device meets multiple regulation requirements with LED open-circuit, short-to-ground, and single LED short-circuit diagnostics. A configurable watchdog also automatically sets fail-safe states when the MCU connection is lost, and, with programmable EEPROM, TPS929121-Q1 can flexibly be set for different application scenarios.