Abstract: A semiconductor device includes a circuit board, a wiring part, a protective coating glass, and a resin part. The circuit board has an approximately rectangular shape. The protective coating glass is disposed on the circuit board and is arranged on an inside of the circuit board in such a manner that an outer-peripheral end of the protective coating glass is away from each of four sides of the circuit board at a first distance and is away from each of four corners of the circuit board at a second distance that is larger than the first distance. The resin part seals the circuit board, the wiring part, and the protective coating glass in such a manner that an outer-peripheral end portion of the circuit board that is located on an outside of the protective coating glass directly contact with the resin part.

Abstract: A resin-sealed semiconductor device includes a metal frame, an electronic substrate, an adhesive agent, a molded resin, and a bonding agent. The electronic substrate includes a first surface having a circuit element wiring part, a second surface facing the metal frame, and a side surface arranged approximately perpendicularly to the first surface and the second surface. The adhesive agent is disposed between the metal frame and the second surface to cover the second surface and a portion of the side surface adjacent to the second surface. The molded resin covers the metal frame and the electronic substrate, and holds the other portion of the side surface adjacent to the first surface. The bonding agent is disposed between the circuit element wiring part and the molded resin so that the molded resin holds the circuit element wiring part through the bonding agent.

Abstract: A protection circuit can be prevented from malfunctioning due to the parasitic operation attributable to the unstable base potential of a transistor. In one embodiment, the protection circuit can be constituted by a reverse transistor system where the bases of transistors are connected to the collectors so that bases and collector potentials are the same. With the above configuration, the base potential is stabilized, and even if a parasitic potential is applied to the base as noise, malfunction associated with transistors turn on due to parasitic operation can be prevented. Since the base potential is stabilized, the protection circuit transistors turn on with greater certainty when a surge current occurs such that the surge current is absorbed by the protection circuit and flows to GND.

Abstract: A semiconductor device includes a circuit board, a wiring part, a protective coating glass, and a resin part. The circuit board has an approximately rectangular shape. The protective coating glass is disposed on the circuit board and is arranged on an inside of the circuit board in such a manner that an outer-peripheral end of the protective coating glass is away from each of four sides of the circuit board at a first distance and is away from each of four corners of the circuit board at a second distance that is larger than the first distance. The resin part seals the circuit board, the wiring part, and the protective coating glass in such a manner that an outer-peripheral end portion of the circuit board that is located on an outside of the protective coating glass directly contact with the resin part.

Abstract: A protection circuit can be prevented from malfunctioning due to the parasitic operation attributable to the unstable base potential of a transistor. In one embodiment, the protection circuit can be constituted by a reverse transistor system where the bases of transistors are connected to the collectors so that bases and collector potentials are the same. With the above configuration, the base potential is stabilized, and even if a parasitic potential is applied to the base as noise, malfunction associated with transistors turn on due to parasitic operation can be prevented. Since the base potential is stabilized, the protection circuit transistors turn on with greater certainty when a surge current occurs such that the surge current is absorbed by the protection circuit and flows to GND.

Abstract: A resin-sealed semiconductor device includes a metal frame, an electronic substrate, an adhesive agent, a molded resin, and a bonding agent. The electronic substrate includes a first surface having a circuit element wiring part, a second surface facing the metal frame, and a side surface arranged approximately perpendicularly to the first surface and the second surface. The adhesive agent is disposed between the metal frame and the second surface to cover the second surface and a portion of the side surface adjacent to the second surface. The molded resin covers the metal frame and the electronic substrate, and holds the other portion of the side surface adjacent to the first surface. The bonding agent is disposed between the circuit element wiring part and the molded resin so that the molded resin holds the circuit element wiring part through the bonding agent.

Abstract: In an ignition system that includes an ignition coil having a primary coil and a secondary coil, a switching element connected between the primary coil and a ground, a battery and a spark plug connected to one end of the secondary coil, an engine abnormal condition detecting device includes a Zener diode connected between the other end of the secondary coil and the ground to allow secondary current flowing in the secondary coil toward the ground, a resistor connected between the secondary coil and the ground to limit the secondary current flowing through the secondary coil to a preset level, a secondary current detecting circuit for detecting an amount of secondary current flowing through the resistor, and an electronic control circuit for determining an abnormal condition of the ignition system with reference to the amount of the secondary current flowing through the resistor.

Abstract: An IGBT driving circuit includes an IGBT connected in series with a primary winding of an ignition coil and a current detecting resistor. A transistor is connected to the gate of the IGBT to apply a gate voltage in response to an ignition signal. A comparator compares a voltage produced across the current detecting resistor with a comparison voltage. An NPN transistor connected to the gate of the IGBT turns on and off in response to the comparison result of the comparator to adjust the gate voltage. The gate voltage is fed back to the detection terminal side of the comparator for oscillation suppression through an oscillation suppressing resistor. A charge/discharge control resistor is connected between the gate of the IGBT and the oscillation suppressing resistor and a diode is connected in parallel with the charge/discharge control resistor, so that the electric current flowing to the IGBT is maintained constant.

Abstract: In an ignition apparatus for an internal combustion engine, an ECU produces an ignition signal to an igniter/coil circuit with an igniter and ignition coil, which in turn sends back a monitor signal for ignition failure determination in the ECU. The ignition signal and the monitor signal are sent through a single signal line. The monitor signal is produced based on a primary current or a secondary current of the ignition coil.