Design of a Wide-Range Adjustable Linear Power Supply

Abstract

Industrial adjustable DC power supplies are mostly analog power supplies that use hardware closed-loop control and rely on mechanical regulation, making it difficult to balance wide range adjustable output and low ripple, and having poor regulation accuracy. To solve this problem, a wide range adjustable and low ripple DC stabilized power supply was designed using TI TPS54360B synchronous Buck converter and MIC29502 low dropout linear regulator. Using STM32F103C8T6 microcontroller as the control core, we independently designed DC-DC feedback loop, LDO feedback loop, and ADC sampling loop to achieve closed-loop control of power system output and real-time monitoring of parameters. The test results show that the system can achieve adjustable output of 1.182V-24.2V, step accuracy of 7mV, ripple of 3mV, maximum output current of 3.3A, efficiency of 88%, with overcurrent and over temperature protection, fully meeting the precision power supply requirements of industrial low-power equipment.