| 摘要 |
PROBLEM TO BE SOLVED: To improve the current control precision without adding circuit to an inductive load controller. SOLUTION: The controller has a current detection resistor R1 in series to a linear solenoid L1 and level shift circuits C1, D1 to which voltages VH, VL are inputted to both ends of the resistor R1 to output higher voltages by fixed voltages than the input voltages. In every fixed period of time, an A/D converter 6 A/D-converts the outputs of the level shift circuits C1, D1 to detect the difference between both converted values as currents flowing in the solenoid L1. An ECU 1 controls the duty ratio of PWM signals for driving power feeding switching elements 22, 21 so that the detected values may be target values. If the duty ratio of the PWM signals is 0%, it A/D-converts the outputs of both circuits C1, D1, and calculates the difference between both converted values as offset values showing the output characteristics difference between the circuits C1, D1. The detected values used for calculating the duty ratio of the PWM signal are corrected, using the offset values.
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