Patent ID: 8644038

Claim:
A current detection circuit for a power semiconductor device having a sense function, the power semiconductor device including a main region and a sense region for current detection and including a main terminal connected to the main region, and a sense terminal connected to the sense region, the current detection circuit comprising: a current-voltage conversion circuit that is coupled to the sense terminal of the power semiconductor device to receive a current to be detected and that converts the current to a voltage signal; an output level regulator that regulates an output level of a current sense signal delivered from the current-voltage conversion circuit; a current direction detection circuit that detects a direction of a current flowing in the power semiconductor device with a sense function based on a current sense signal delivered from the current-voltage conversion circuit and that provides a direction signal to an external CPU; a first variable voltage source circuit that generates a correction gain according to a gain-setting signal delivered by the CPU and corresponding to the direction of the current flowing in the power semiconductor device with a sense function; a second variable voltage source circuit that generates a correction offset according to an offset-setting signal delivered by the CPU and corresponding to the direction of the current flowing in the power semiconductor device with a sense function; and an adder circuit that adds an output of the first variable voltage source circuit and an output of the second variable voltage source circuit and supplies an added result to the current-voltage conversion circuit; wherein an electric potential at the sense terminal is adjusted corresponding to the added result to perform correction for a difference between a characteristic of the main region and a characteristic of the sense region.