| 摘要 |
A switching power supply circuit having a standby battery for power supply comprises an input rectifier module (10), a PWM switching control module (20), a transformer module (30), an output rectifier diode (40), a negative feedback module (50), a standby battery (80), an isolation diode unit (70), and a Zener diode (60). The positive electrode of the output rectifier diode is connected to the positive output end of the transformer module; the negative electrode of the output rectifier diode is connected to the negative electrode of the isolation diode unit; the positive electrode of the isolation diode unit is connected to the positive electrode of the standby battery; the negative electrode of the standby battery is connected to the negative output end of the transformer module; the negative electrode of the Zener diode is connected between the negative electrode of the isolation diode unit and the negative electrode of the output rectifier diode; one end of the negative feedback circuit module is connected to the positive electrode of the Zener diode, and the other end thereof is connected to the control port of the PWM switching control module. The circuit can reduce loss in output of a switching power supply and improve conversion efficiency of the switching power supply. |
