The utility model discloses a sluggish type power supply circuit, include: input circuit, switch combinatorial circuit, sampling and control circuit, feedback circuit and output circuit. Input circuit is connected to power input end, carries out the rectification and provides the insulation blocking of input the power input. Switch combinatorial circuit is connected to input circuit, opens or turn -off the output with control power output end. Opening or turn -offing according to control switch combinatorial circuit is as a result relatively compared with control circuit sampling output voltage and with output voltage and reference voltage to the sampling. Feedback circuit connects between switch combinatorial circuit and sampling and control circuit, and switch combinatorial circuit passes through feedback circuit makes the comparison action of reference power supply chip produce sluggish effect to sampling and the positive feedback signal of control circuit output, positive feedback signal. Output circuit is connected to switch combinatorial circuit, carries out filtering and provides the insulation blocking of output switch combinatorial circuit's output, and its output is as output of sluggish type power supply circuit.