Buck converter with high efficiency gate driver providing extremely short dead time
A buck converter has a driver circuit with a drive transformer that provides complementary voltages to the buck converter switches. The drive transformer may have two secondary windings, with one winding for each converter switch. As one converter switch experiences a rising gate voltage, the other converter switch experiences a falling gate voltage. Since both converter switches are controlled by the same driver switches, the converter switch dead time is very small. Preferably, at least one converter switch has a voltage shift circuit connected to the gate electrode. Adjustment of the voltage shift magnitude will advance or delay the turn on and turn off times of the switch. Hence, the converter switch dead time can be precisely adjusted by varying the voltage shift magnitude. Preferably, the converter switch dead time is less than 1 or 2 nanoseconds.