关键词: 汽车收音机；自动开机；电源电路；静电抑制器；ESD 管漏电电流

Abstract: A car radio has the problem of auto-power-on at zero kilometers and after-sales stage, which will cause battery feeding and other consequences. Starting from the circuit principle of the radio, this paper tests the reason of triggering auto-power-on by means of oscilloscope and other tools, locks the failed electronic components, and makes metallographic slice analysis to find the reason of the failure of the electronic components. According to the failure phenomenon of electronic components, the packaging is further studied, the end factors are investigated one by one, and the unfavorable factors are optimized. The tracking results show that the improved component performance and higher yield significantly reduce the defect rate of the radio and improve customer satisfaction. This paper introduces the radio power supply circuit and analyzes the problem of auto-power-on, which provides some solutions for other on-board electrical faults.

Key words: Car radio; Auto-power-on; Power circuit; Static eliminator; ESD diode leakage current