Controlling of dc-dc buck converters using microcontrollers

This paper presents a technique to digitally control the output voltage of a DC-DC converter via a microcontroller. The voltage regulation and controlling were achieved utilizing an LM2596 buck converter. A digital potentiometer MCP41050 is utilized to smoothly control the regulated output DC voltage via the SPI digital protocol. The proposed design is manufactured and tested for various loads. This device is considered as a step-down voltage regulator capable of driving 3A load with high efficiency, excellent linearity, source-voltage variation, and load regulation. The results show that the system can control the output voltage with satisfactory performance and high accuracy. With various loads, the proposed system shows a mean square error of 0.015±0.037 volts tested with a regulated voltage of 5 volts. The efficiency improves from about 80% to around 91% at a 1 kΩ load. This design eliminates the possible errors that arise when manually varying the voltage of the buck converter; by means of using a microcontroller. Such a system ensures a proper digitally controlled output voltage with a better performance, which can be applied in various applications. © 2021, North Atlantic University Union NAUN. All rights reserved.