Patent ID: 7369421

Claim:
A full bridge driver connected to a first side of a transformer and a DC power, the full bridge driver comprising: a control chip having a first output terminal and a second output terminal, the first and second output terminals separately outputting a first control signal and a second control signal both with a duty cycle smaller than 50%; a first cut-off switch coupling to the first output terminal of the control chip; a first diode having a positive (P) terminal coupling to the DC power; a first resistor coupling to a negative (N) terminal of the first diode and the first cut-off switch; a first capacitor coupling to the negative (N) terminal of the first diode and one end of the first side of the transformer; a first N-MOS having a gate coupling to the first cut-off switch and a drain coupling to the DC power and a source coupling to one end of the first side of the transformer; a second N-MOS having a gate coupling to the first output terminal of the control chip and a drain coupling to the source of the first N-MOS and a source coupling to a reference terminal; a second cut-off switch coupling to the second output terminal of the control chip; a second diode having a positive (P) terminal coupling to the DC power; a second resistor coupling to a negative (N) terminal of the second diode and the second cut-off switch; a second capacitor coupling to the negative (N) terminal of the second diode and another end of the first side of the transformer; a third N-MOS having a gate coupling to the second cut-off switch and a drain coupling to the DC power and a source coupling to another end of the first side of the transformer; and a fourth N-MOS having a gate coupling to the second output terminal of the control chip and a drain coupling to the source of the third N-MOS and a source coupling to the reference terminal.