Peak current-mode control for a boost converter using an 8-bit microcontroller

In a current-mode control (CMC) system, the inductor current has a fundamental frequency equal to the switching frequency that far exceeds the maximum sampling rate of most microcontroller A/D converters. In order to demonstrate the feasibility of a microcontroller-based CMC DC-DC converter, a peak current controller for a boost converter operating in the continuous conduction mode has been designed and implemented using a PIC16C782 microcontroller. Practical issues in designing a digital CMC converter are briefly discussed. Experimental results are presented, and encouragingly demonstrate the performance that a microcontroller-based CMC DC-DC converter can achieve. The digital controller has been compared to an analog controller based on a UC3842.