摘要
提出了一种用于原边反馈型AC-DC变换器的高精度过零检测电路架构。该检测机制基于系统谐振纹波,通过对纹波的放大以及与基准电压的比较确定反激变换器系统二次侧电流过零点。其与传统通过反馈电压采样检测方式相比,克服了制程偏移对检测结果的影响,从而实现大幅提升了检测精度。该检测电路架构通过某0.35μm CMOS工艺实现,经实测验证,检测误差<1.5%。
A high precision zero crossing detection circuit applied in PSR AC - DC converter is put forward inthis paper,the detection method is based on the resonance ripple of the converter system,by amplifying the ripplevoltage and comparing the amplified signal witli reference voltages,the moment of secondary current decreases to zerocan be precisely determined. Compared witii traditional detection approach that by sensing the feedback voltage,themetiiod proposed in this paper overcomes the influence of tiie variation of process to the detection resudetection accuracy is greatly improved. The circuit mentioned in this paper has been realized in a 0. 35 #m CMOSprocess,experimental results verify that tiie detection accuracy can reach a level less than 1 .5%.
出处
《电子科技》
2017年第12期21-24,共4页
Electronic Science and Technology
