Switch power supply paralleled current sharing control circuit applying UC3907

The invention discloses a switch power supply paralleled current sharing control circuit applying UC3907 and belongs to the technical field of electric power electronics. The voltage sampling and the current sampling adopt LEM (laser energy monitor) modules based on Hall devices, and higher output voltage and current can be collected; an output voltage control outer ring of a switch power supply adopts a voltage error amplifier inside the UC3907, and a current sharing control inner ring adopts a regulating amplifier inside the UC3907; in a compensating loop, greater gains can be obtained during the low frequency when a mode of serially connecting a resistor R9 with a capacitor C5 is adopted, and the gain can be fast increased when being lower than a certain frequency, so higher control precision can be reached, a capacitor C6 is parallelly placed on a serial connection branch of the R9 and the C5, the high-frequency gain drops, and the high-frequency noise peak is prevented from being transmitted to the output end; and the non-isolated connection is adopted between the UC3907 and a driving control PWM (pulse width modulation) signal generator SG3525, and the control response speed and the control precision are accelerated and improved.