Abstract: An injection control device includes: a boost controller performing a boost switching control of a boost switch to charge a boost capacitor and supplying a boost power from a battery power supply; a boost voltage monitor monitoring the boost voltage; and a boost monitor timing controller setting a section from a predetermined time after an on-edge of the boost switch to an off-edge timing in a section monitor mode as a boost monitor section. The boost controller stops boosting by stopping the boost switching control when the boost voltage is equal to or higher than a boost stop threshold value in the boost monitor section.

Abstract: An injection control device includes: a boost controller performing a boost switching control of a boost switch to charge a boost capacitor and supplying a boost power from a battery power supply; a boost voltage monitor monitoring the boost voltage; and a boost monitor timing controller setting a section from a predetermined time after an on-edge of the boost switch to an off-edge timing in a section monitor mode as a boost monitor section. The boost controller stops boosting by stopping the boost switching control when the boost voltage is equal to or higher than a boost stop threshold value in the boost monitor section.

Abstract: An air-fuel ratio (A/F) sensor control device includes: an impedance detector detecting an impedance of an A/F sensor; and a pump current controller performing a digital control on a supply of electric current to the A/F sensor. The pump current controller includes a PID calculator calculating an instruction current value according to a difference of two input values, i.e., the difference between a PID control target value and a detection value of an inter-terminal voltage of a Nernst cell; and a protection clamper limiting a supply of electric current to a pump cell based on the instruction current value and the impedance.

Abstract: An air-fuel ratio (A/F) sensor control device includes: an impedance detector detecting an impedance of an A/F sensor; and a pump current controller performing a digital control on a supply of electric current to the A/F sensor. The pump current controller includes a PID calculator calculating an instruction current value according to a difference of two input values, i.e., the difference between a PID control target value and a detection value of an inter-terminal voltage of a Nernst cell; and a protection clamper limiting a supply of electric current to a pump cell based on the instruction current value and the impedance.