Abstract: In a load-driving apparatus with a FET between a battery and a load, an overcurrent detection circuit has a function generation circuit with a voltage divider circuit and a comparator. The voltage divider circuit has a pair of resistors connected to a drain of the FET, and a Zener diode connected to a connection point in parallel to the second resistor. The comparator compares a reference voltage at the connection point with a variable voltage of the FET, and outputs an overcurrent detection signal when the variable voltage becomes lower than the reference voltage. When no overcurrent exists and the battery voltage is not decreasing, the connection point is kept at a breakdown voltage of the Zener diode, and the difference with respect to the source voltage of the FET becomes particularly large. The comparator therefore does not erroneously output an overcurrent detection signal even when noise enters the system.

Abstract: In a load-driving apparatus with a FET between a battery and a load, an overcurrent detection circuit has a function generation circuit with a voltage divider circuit and a comparator. The voltage divider circuit has a pair of resistors connected to a drain of the FET, and a Zener diode connected to a connection point in parallel to the second resistor. The comparator compares a reference voltage at the connection point with a variable voltage of the FET, and outputs an overcurrent detection signal when the variable voltage becomes lower than the reference voltage. When no overcurrent exists and the battery voltage is not decreasing, the connection point is kept at a breakdown voltage of the Zener diode, and the difference with respect to the source voltage of the FET becomes particularly large. The comparator therefore does not erroneously output an overcurrent detection signal even when noise enters the system.

Abstract: A target torque is calculated as a proportion PI relative to a torque generated by an engine at a basic ignition timing. An ignition timing correction amount is calculated based on this proportion PI, and by correcting the ignition timing by this correction amount, an ignition timing correction which precisely matches a torque-down request is performed rapidly and accurately.

Abstract: An exhaust passage is connected to an intake passage of an engine through an exhaust recirculating valve. A target opening of the exhaust recirculation valve is first set according to a target exhaust recirculation rate depending on engine running conditions, the total intake air flow cross-sectional area of the engine, and a first correction value set according to the exhaust pressure. By applying this corrected value, the same EGR is always obtained on both low ground and high ground regardless of the engine running conditions. Preferably, the target opening is further corrected by a second correction value set based on the exhaust temperature.