Driving circuit for driving a semiconductor device at high speed and method of operating the same

A method of driving a semiconductor device comprising the steps of:

• applying a voltage difference between a cathode and an anode of a plurality of voltage-driven switching elements connected in series;
• generating an intermediate voltage from a first voltage-driven switching element of said plurality of voltage-driven switching elements;
• and
• applying a negative bias to a gate of a second voltage-driven switching element of said plurality of voltage-driven switching elements, which is located on a higher voltage side than that of said first voltage-driven switching element, by using the intermediate voltage generated while said first voltage-driven switching element is off.

A method of driving a semiconductor device comprising the steps of:

• applying a voltage difference between a cathode and an anode of a voltage-driven switching element;
• generating a displacement current from a circuit which is connected between the cathode and anode of said voltage-driven switching element when the voltage applied to said voltage-driven switching element increases;
• emitting light from a light-emitting element on the basis of the displacement current generated;
• and
• applying a negative bias to a gate of said voltage-driven switching element by using a photovoltaic power of a photovoltaic element receiving the light emitted.

A semiconductor device comprising:

• a voltage-driven switching element having a cathode and an anode connected to a voltage;
• a voltage-lowering circuit connected between the cathode and anode of said voltage-driven switching element to receive said voltage and generating a stabilized intermediate voltage;
• an enhancement-type MOSFET charging switching element charging a gate of said voltage-driven switching element using the stabilized intermediate voltage generated by said power-lowering circuit;
• a depletion-type MOSFET discharge switching element discharging the gate of said voltage-driven switching element;
• and
• a photovoltaic element generating a photovoltaic power to drive said charging switching element and said discharging switching element.

A semiconductor device comprising:

• a plurality of voltage-driven switching elements connected in series, each having a cathode and an anode, in which a voltage difference is to be applied between the cathode and anode;
• intermediate voltage generating circuit for generating an intermediate voltage from a first voltage-driven switching element of said plurality of voltage-driven switching elements;
• and
• a circuit for applying a negative bias to a gate of a second voltage-driven switching element of said plurality of voltage-driven switching elements, which is located on a higher voltage side than that of said first voltage-driven switching element, using the intermediate voltage generated by said intermediate voltage generating circuit while said second voltage-driven switching element is off.

A semiconductor device comprising:

• a voltage-driven switching element having a cathode and an anode, in which a voltage difference is to be applied between the cathode and anode;
• a displacement current generating circuit connected between the cathode and anode of said voltage-driven switching element, for generating a displacement current when the voltage applied to said voltage-driven switching element increases;
• a light-emitting element for emitting light when the displacement current is generated by said displacement current generating circuit;
• and
• a photovoltaic element for generating a photovoltaic power by receiving the light emitted by said light-emitting element, and thereby applying a negative bias to a gate of said voltage-driven switching element.

A semiconductor device formed as one package, comprising:

• a plurality of voltage-driven switching elements, each of the voltage-driven switching elements having a cathode and an anode with a voltage connected between the cathode and the anode;
• a gate power-supply circuit formed as one chip and connected between the cathode and anode of each of said plurality of voltage-driven switching elements and receiving said voltage, said gate power-supply circuit generating a stabilized intermediate voltage used as a gate charging voltage for each of said plurality of voltage-driven switching elements;
• and
• a light trigger circuit formed as one chip, said light trigger circuit including,
• an enhancement-type MOSFET charging switching element for charging a gate of each of said plurality of voltage-driven switching elements using the stabilized intermediate voltage generated by said gate power-supply circuit,
• a depletion-type MOSFET discharging switching element for discharging the gate of each of said plurality of voltage-driven switching elements, and
• a photovoltaic element generating photovoltaic power to drive said charging switching element and said discharging switching element.