Patent ID: 8179169

Claim:
A driving circuit for driving a transistor comprising: a variable resistor, wherein the transistor includes a control electrode, a first electrode and a second electrode, the variable resistor is coupled with the control electrode of the transistor, the variable resistor includes a depletion layer, which is expandable in accordance with a voltage between the first electrode and the second electrode of the transistor, the depletion layer is capable of controlling a current path of the variable, the variable resistor has a variable resistance, the variable resistance is controlled to decrease when the voltage between the first electrode and the second electrode of the transistor is decreased, the variable resistance is controlled to increase when the voltage between the first electrode and the second electrode of the transistor is increased, the variable resistor further includes a P conductive type semiconductor region and a pair of N conductive type semiconductor regions, the pair of N conductive type semiconductor regions contacts and sandwiches the P conductive type semiconductor region, the P conductive type semiconductor region is electrically coupled with the control electrode of the transistor, and the pair of N conductive type semiconductor regions is electrically coupled with the first electrode of the transistor.