用于原边反馈式反激变换器的电压采样电路

A Voltage Sampling Circuit Applied in Primary-Side Regulation Flyback Converter

提出了一种应用于原边反馈式反激变换器的电压采样电路。该电压采样电路通过三路依次采样,在不同模式下使用对应的算法,得到最接近真实值的采样值。仿真结果表明,在采样频率10MHz的条件下,该电压采样电路在CCM和DCM模式下均能正常工作,在DCM模式下的误差可低至0.8%。

A voltage sampling circuit applied in primary-side regulation flyback converter was proposed.In order to get the accurate sampling value in different modes,the proposed sampling circuit was adopted to get three voltage waves through sequential sampling.The sampling value which was closest to the accurate value was provided by using corresponding algorithms.Simulation results showed that the circuit could work properly in both CCM and DCM modes under the sampling frequency of 10 MHz,and the sampling error in DCM mode could even be limited to 0.8%.