The invention discloses a method and circuit for converting alternating-current
sine wave signals into direct-current step wave signals. The method comprises the steps that (1) the alternating-current
sine wave signals are rectified into direct-current head signals; (2) the
head wave signals are transmitted into a plurality of
voltage adjusting devices with different amplitudes, and are divided into
multiple stages of
voltage signals; (3) the
voltage signals are respectively transmitted into a
constant current device, voltage
signal waves form flat-topped
waves, all flat-topped wave voltage signals are connected in sequence, and the direct-current step wave signals are obtained. The circuit comprises a
rectifier bridge circuit, the voltage adjusting devices and a plurality of
constant current control devices, the
rectifier bridge circuit rectifies the alternating-current
sine wave signals into the direct-current
head wave signals, the voltage adjusting devices are connected in parallel to form a network, the voltage adjusting set values of the voltage adjusting devices are different, the direct-current
head wave signals are divided into the multi-stage signals with different amplitudes, the number of the
constant current control devices is equal to that of the voltage adjusting devices, the constant current control devices are correspondingly connected with the voltage adjusting devices respectively, and used for controlling the currents of the voltage adjusting devices to be kept constant, and the output signals of the voltages adjusting devices are made to be the flat-topped
waves. All the flat-topped wave signals are connected in sequence, and the direct-current step wave signals are formed.