CURRENT DETECTION CIRCUIT AND SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

PROBLEM TO BE SOLVED: To provide a current detection circuit capable of detecting current while being protected from overvoltage and overcurrent which is easily generated according to an induced voltage or an induced current, and to provide a semiconductor integrated circuit device incorporated with the current detection circuit.SOLUTION: Transistors Q8 and Q12 are current-mirror connected to each other, and accordingly the approximately same current as a collector current of the transistor Q8 can pass as a collector current of the transistor Q12. Transistors Q11 and Q9 are current-mirror connected to each other, and accordingly the same current as a collector current of the transistor Q11 can pass as collector currents of the transistors Q9 and Q10. Then, the same collector current as the collector current of the transistor Q8 can pass through a transistor Q7, and voltages between collectors and emitters of the transistors Q7 and Q8 can be controlled to the approximately same voltage. A detection circuit S detects an output sense signal voltage Vs of an I/V conversion circuit, and thereby can estimate a collector current of a main transistor Q1.