| 摘要 |
PROBLEM TO BE SOLVED: To automatically and efficiently adjust an electric current detecting signal by arranging a switching means for inputting and supplying the electric current detecting signal of a motor to a control part, performing PWM driving on the switching means by the control part, and adjusting gain of the electric current detecting signal by changing a duty. SOLUTION: An electronic switch 40 is arranged as a switching means between an MCU 50 and an electric current detecting circuit 38 for detecting an electric current flowing to a motor 20 for generating steering assisting force, and a motor detecting current (i) is inputted to an A/D terminal of the MCU 50 through a smoothing (leveling) circuit of fixed resistances R1, R2 and a capacitor C. A multiplier (a time sharing multiplying circuit) is formed by controlling the electronic switch 40 in an ON/OFF system on the basis of a duty of a PWM signal from a PWM terminal of the MCU 50, and an output level Vout of the multiplier is adjusted by changing a duty Duty of the PWM signal. An output level Vout of this multiplier is inputted to the A/D terminal of the MCU 50 through the smoothing circuit. |
