Abstract: In an electric load driving device, in the case of a high-side output mode, an output FET is supplied, when connected with a higher-potential side than a load, at its gate with a boosted voltage higher than a battery voltage in response to one control signal as selected from two control signals by a switch signal. In the case of a low-side output mode, the FET is supplied, when connected with a lower-potential side than the load, at its gate with the battery voltage in response to the selected signal. These cases are switched in response to a signal indicating the bit value of the output mode setting data which are stored in advance in a nonvolatile memory.

Abstract: A microcomputer receives a position detection signal from a throttle angle sensor, and produces drive command signals to a drive circuit to control the position of a throttle valve to a target position through a motor. The current supplied to the motor is limited to less than a maximum value in a current variation zone in a normal motor operation range, when the throttle valve cannot be controlled to the target position, that is, when it is locked to the same position. The microcomputer produces a signal to cancel the current limitation to the motor, when it detects from the position detection signal of the throttle angle sensor that the throttle valve undergoes a predetermined change under the current limitation condition.

Abstract: A microcomputer produces to a drive circuit drive command signals for starting to drive and braking a motor so that the position of a throttle valve is controlled to a target position. A current supplied to the motor is limited not to exceed a first current limitation value at the time of motor drive start and braking. When the current limitation continues for a predetermined time period, the current is further limited not to exceed a second current limitation value. The microcomputer detects switching of motor current supply direction. When the current supply direction is switched, a reset command signal is produced to reset a timer operation for a current limitation continuation determination.

Abstract: A plurality of ceramic circuit boards mounted with heat-generative driving transistors and other electronic parts are bonded to a heat radiating fin, and the heat radiating fin is connected to a motherboard. Heat generated by the driving transistors can efficiently be absorbed and dissipated by the heat radiating fin, and assembling work necessary for combining the components to the motherboard can be reduced. The electronic parts, wiring patterns and the like on the circuit boards can simultaneously be encapsulated in a resin or the like after bonding the circuit boards to the heat radiating fin, packaging work can be reduced.