Patent ID: 8598942

Claim:
A current correction circuit for a power semiconductor device, the current correction circuit comprising: a power semiconductor device with a sensing function, including a main region through which flows a main current which is a main portion of an input current, a sense region through which flows a sense current which is a sense portion of the input current, a main terminal connected to the main region and a sense terminal connected to the sense region; a temperature detecting unit including a temperature detecting device that detects an ambient temperature of the power semiconductor device and a terminal that outputs the detected ambient temperature; and a current correcting unit connected to the sense terminal and the temperature detecting unit, and including: a current detecting unit including a current-voltage conversion circuit that converts the sense current from the sense terminal into a voltage; a correction unit including an arithmetic circuit that performs a predetermined operation on the basis of the detected ambient temperature and a set value corresponding to the detected ambient temperature, and outputs a control signal for correcting a variation in a current sense ratio due to a variation in the detected ambient temperature of the power semiconductor device; and a variable voltage source that outputs a variable voltage that varies based on the control signal, wherein each of an output terminal of the current detecting unit and an output terminal of the correction unit is connected to a respectively corresponding control input terminal of the variable voltage source, wherein an output terminal of the temperature detecting unit is connected to a temperature information input terminal of the correction unit, wherein the sense terminal of the power semiconductor device is connected to a current input terminal of the current detecting unit, and wherein the output voltage of the variable voltage source is adjusted according to the detected ambient temperature and a current flowing to the sense terminal, to adjust the potential of the sense terminal, thereby correcting a characteristic difference between the main region and the sense region of the power semiconductor device.