Mitsubishi Electric Corporation

Hiroshi Mizukami

Hisanori Nobe

Yoshiyuki Sera

Koji Ueda

Toru Ikeda

Tom Ikeda

An electronic control device includes a first pull-up resistor connected between a power supply and a switch, a series circuit of a transistor and a second pull-up resistor with a resistance value lower than that of the first pull-up resistor, connected in parallel with the first pull-up resistor, and a microcomputer, an output port of which is connected to a base terminal of the transistor and which controls a turning on and off of the transistor using a signal output from the output port. A connection point of the switch, the first pull-up resistor, and the second pull-up resistor is connected to a first analog measurement port of the microcomputer, a power supply is connected to a second analog measurement port of the microcomputer, and current flowing into the switch is detected using a value of voltage input into the first analog measurement port.

Electronic control device

An internal-combustion-engine electronic control system according to the present invention is provided with a power switching device that applies or shuts off a primary current of an ignition coil of an internal combustion engine so that at the secondary side of the ignition coil, there is generated a voltage for making an ignition plug of the internal combustion engine produce a spark discharge; and a control unit that turns on or off the power switching device. The internal-combustion-engine electronic control system is characterized in that the control unit is provided with a circuit unit that makes the power switching device softly shut off so as to prevent the ignition plug from producing the spark discharge, and in accordance with the characteristics of the power switching device, the control unit changes the characteristics of the soft shutoff halfway through the shutoff operation.

Electronic control of a spark plug for an internal combustion engine

A control circuit is provided including a trigger circuit having a capacitor connected between a pulse generator and a second switching element, and a latch circuit connected via a diode, between a junction of a load with a first switching element and the control terminal of the second switching element, wherein when the pulse generator outputs a drive signal, both of the first switching element and the second switching element are turned on and the second switching element is held in the ON state through the latch circuit by a voltage at the junction. When the drive signal is stopped, both of the first switching element and the second switching element are turned off; meanwhile if the load is short-circuited, the first switching element and the second switching element are turned off through the latch circuit by the voltage at the junction.

Growing community of inventors

Chiyoda-ku, Japan

Hiroshi Mizukami