基于低功率PIC16F887单片机的控制系统抗干扰能力改进

Research on improving anti interference capability of control system based on low power PIC16F887

针对基于低功率PIC16F887单片机控制系统的电磁干扰问题,设计了一种稳定的电容降压电源电路。通过电快速瞬变脉冲群(EFT/B)试验,测试了PIC16F887单片机在不同电源等级中的抗电磁干扰能力,提出了采用两级稳压电路增强电源端抗干扰能力的方法并设计了电路。实验结果表明,低功率PIC16F887单片机控制系统在电容降压电路中能稳定工作,5V系统中的EFT/B抗干扰能力要强于3.3V系统,电源端抗EFT干扰能力达到IEC61000-4-4严酷等级第4级的要求。

Aiming at the electromagnetic interference of control systems based on low power SCM PIC16F887, a stable capacitive step-down power supply is presented. The anti interference capability of PIC16F887 is tested under different powers with electrical fast transient bursts （EFT/ B）. In order to enhance the anti interference capability of the power supply, a two-stage voltage regulation circuit is presented. The experimental results show that the low power control system based on PIC16F887 can work stably in capacitive step-down circuit, the anti interference capability of 5V system is stronger than that of 3.3V system, and the anti interference capability of the power supply meets severity level 4 of IEC61000-4-4 with the improved measures