[Zhejiang University of Science and Technology Electrical Competition] LED Flash Power Supply (Question H)

This project won the second prize in the 5th Electronic Design Competition of Zhejiang Sci-Tech University

Team number: ZSTU

Team members: Zheng Jiahui, Fan Qingqing, Liang Rufeng

Instructor: Jin Hai

"School Level Electronic Design Competition" Design Summary Report

Title: Title H "LED Flash Power Supply" Introduction to the topic: This system is mainly composed of a single-chip microcomputer module, a bidirectional DC/DC boost control circuit, a current detection circuit and buttons. In order to achieve the design goal of a high-efficiency DC constant current power supply, the system uses  a DC/DC  voltage conversion circuit  to increase the low voltage of 3 ~ 3.6V  input from the external power supply to a maximum  output of 10.5V  . The user can choose In the output mode, the analog signal is converted into a digital signal through the current detection circuit and input into the STM32  microcontroller to achieve real-time monitoring. The constant current software based on  the PID  algorithm is used to control  the PWM  signal output by the microcontroller, thereby forming a closed loop with feedback and automatic adjustment. The main functions of the system include: continuous output mode and pulsating output mode. There are three gears of 100 , 150 and 200mA  in the continuous output mode  . The relative error of the output current is less than  2% . When the output current is at  the 200mA  gear, the output voltage is  10V and the efficiency is not less than  80% . When the output voltage reaches  10.5V  , it has Automatic alarm function; there are three levels of 300 , 450 and 600mA  in pulse mode  , the relative error is less than  5% , the rise time and fall time are not more than  100us , and the current overshoot is not more than  10% .