关键词: 微控制器, 浪涌, 瞬态电压抑制管, 热插拔

Abstract: Customers reported that two CKS32F030K6T6-based motor boards failed to drive motors normally, with measurements revealing a short circuit at the chip power supply pins. Technical analysis of the faulty board revealed that the general-purpose input pin (PA7) of the microcontroller unit (MCU) was damaged by an abnormal voltage surge, causing a short circuit between the positive power supply input pin (VDD) and the negative power supply input pin (GND). On-site inspection of the customer's circuit diagram showed that the damaged pin lacked surge protection measures. The testing process based on the actual application scenarios of the customer's circuit was optimized to avoid hot-swapping. In addition, parallel bidirectional transient voltage suppression (TVS) diodes and series current-limiting resistors were added to the MCU port pins to suppress surge voltage and mitigate damage risks.

Key words: microcontroller unit, surge, transient voltage suppression, hot plug