基于UC3845反激式开关电源设计及其在测井仪的应用

Design of UC3845 Fly-back Switching Power Supply and Its Application in Logging Instrument

文章介绍了基于电流型PWM控制器UC3845的反激式开关电源,论述了设计原理、参数计算及实例应用。基于该类开关电源具有输入电压范围较宽、结构简单、外围电路元器件少、输出电压稳定等优势,将设计实例应用于测井仪井下探管直流电源系统。实测表明设计的基于UC3845反激式开关电源输出稳定,±5 V电源输出纹波系数小于0.8%,±15 V电源输出纹波系数小于0.5%,能够满足测井仪井下探管对于直流电源的应用需求。

The UC3845 fly-back switching power supply was introduced in the design principle,parameter calculation and its application case. The designed power supply has the advantages of wide input voltage range,simple structure,few peripheral circuit components and stable output voltage. The actual application in the logging probe DC power showed that the designed power supply output is stable,the ripple coefficient of ±5V is less than 0.8%,the ripple coefficient of ±15V is less than 0.5%,which can meet the application requirements of the DC power supply for logging probe.