Switch driving circuit

A switch driving circuit for driving a full-controlled power switch, the switch driving circuit comprising:

• a pulse-width modulation unit for converting a driving input signal into a positive-negative narrow pulse-width signal;
• a pulse transformer having a primary side and a secondary side, wherein the primary side is coupled to the pulse-width modulation unit and the positive-negative narrow pulse-width signal is transferred to the secondary side through the pulse transformer;
• an anti-interference module coupled to the secondary side, wherein the positive-negative narrow pulse-width signal comprises a plurality of positive pulses and a plurality of negative pulses, each of the positive pulses and the negative pulse has a pulse amplitude, the anti-interference module filters out the positive pulses or the negative pulses which the pulse amplitude does not reach an effective threshold, and the anti-interference module suppress a common-mode noise caused by a high voltage transient variation produced when the full-controlled power switch is turned on or turned off;
• a pulse-width demodulation unit coupled to the anti-interference module, for converting the filtered positive-negative narrow pulse-width signal into a driving output signal;
• and
• a driving-power amplifier coupled between the pulse-width demodulation unit and the full-controlled power switch,
• wherein each of the driving input signal and the driving output signal is a pulse-width modulation signal, the positive pulses of the positive-negative narrow pulse-width signal correspond to rising edges of the driving input signal or the driving output signal, respectively, and the negative pulses of the positive-negative narrow pulse-width signal correspond to falling edges of the driving input signal or the driving output signal, respectively.