Igniter

An igniter comprising:

• a switching element connected to a primary winding of an ignition coil,
• a control circuit section configured to control operation of the switching element, and
• a protection element electrically connected to the control circuit section to electrically protect the control circuit section,
• wherein the switching element and the protection element are formed in the same semiconductor chip,
• the igniter further includes, as the protection element, a protective resistor as a resistor arranged on a current path from a DC power source to the control circuit section,
• a resistor protection Zener diode having a breakdown voltage lower than a dielectric strength voltage of the protective resistor is connected in parallel with the protective resistor, and
• the resistor protection Zener diode is formed together with the switching element and the protective resistor in the semiconductor chip.

An igniter comprising:

• a switching element connected to a primary winding of an ignition coil,
• a control circuit section configured to control operation of the switching element, and
• a protection element electrically connected to the control circuit section to electrically protect the control circuit section,
• wherein the switching element and the protection element are formed in the same semiconductor chip,
• the igniter further includes, as the protection element, a protective resistor as a resistor arranged on a current path from a DC power source to the control circuit section,
• the switching element is an IGBT,
• the semiconductor chip includes a field oxide film for element separation,
• a gate electrode of the IGBT and the protective resistor are made of polysilicon,
• the protective resistor is formed on the field oxide film
• the resistor protection Zener diode having the breakdown voltage lower than the dielectric strength voltage of the protective resistor is connected in parallel with the protective resistor, and
• the resistor protection Zener diode is made of polysilicon, and is formed at a position adjacent to the protective resistor on the field oxide film.

An igniter comprising:

• a switching element connected to a primary winding of an ignition coil,
• a control circuit section configured to control operation of the switching element, and
• a protection element electrically connected to the control circuit section to electrically protect the control circuit section,
• wherein the switching element and the protection element are formed in the same semiconductor chip,
• the igniter further includes, as the protection element, a protective resistor as a resistor arranged on a current path from a DC power source to the control circuit section,
• the igniter further includes a semiconductor chip lead frame on which the semiconductor chip is mounted, and
• a control circuit lead frame on which the control circuit section is mounted,
• wherein the semiconductor chip lead frame is formed thicker than the control circuit lead frame.

An igniter comprising:

• a switching element connected to a primary winding of an ignition coil,
• a control circuit section configured to control operation of the switching element, and
• a protection element electrically connected to the control circuit section to electrically protect the control circuit section,
• wherein the switching element and the protection element are formed in the same semiconductor chip,
• the igniter further includes a protection Zener diode configured to keep voltage applied to the control circuit section at a constant value as the protection element,
• the igniter further includes a voltage detection resistor configured to detect voltage applied from the DC power source to the semiconductor chip, and
• an overvoltage protection circuit configured to forcibly turn off the switching element in a case where the applied voltage reaches higher than a preset value.