Abstract:

As an efficient energy conversion power device,switching power supply is widely used in various industries.Aiming at the problem of feedback power supply of switching power supply,the working principle and key problems are analyzed,a voltage-doubling feedback power supply circuit is desigued through theoretical calculation and simulation analysis,the correctness of the design scheme is verified.Finally,the circuit is applied to a 5 V/40 A forward synchronous rectification switching power supply.The measured feedback voltage fluctuates only by 1.5 V.The results show that the circuit has high stability and practicability,which is of great significance for improving the efficiency and reliability of switching power supply.

Key words: switching power supply, feedback power supply, voltage-doubling, synchronous rectification