Protection circuit
AssigneesAutonetworks Technologies, Ltd., Sumitomo Wiring Systems, Ltd., Sumitomo Electric Industries, Ltd.
InventorsShuji Mayama, Isao Isshiki
Life of this patent
Estimating the term…
Abstract
A protection circuit, to be provided for a circuit arrangement having an inductive load and an FET as an N-channel MOS transistor provided upstream of the load with respect to a flow of power current, the FET controlling an energization state of the load, the protection circuit includes a first connection changer interposed on a connection line between a gate of the FET and a gate drive voltage supply source, the first connection changer changing a connection state between a first connection state in which the gate is connected to the gate drive voltage supply and a second connection state in which the gate is connected to a ground.
Claims10
A protection circuit, to be provided for a circuit arrangement having an inductive load and an FET as an N-channel MOS transistor provided upstream of the load with respect to a flow of power current, the FET controlling an energization state of the load, the protection circuit comprising:
- a first connection changer interposed on a connection line between a gate of the FET and a gate drive voltage supply source, the first connection changer changing a connection state between a first connection state in which the gate is connected to the gate drive voltage supply and a second connection state in which the gate is connected to a ground;
- and
- a first resistor interposed between the gate and a source of the FET,
- wherein the protection circuit does not include a zener diode, and protects from overvoltage generated by the load upon discontinuing power to the load.
A protection circuit, to be provided for a circuit arrangement having an inductive load and an FET as an N-channel MOS transistor provided upstream of the load with respect to a flow of power current, the FET controlling an energization state of the load, the protection circuit comprising:
- a first connection changer interposed between a portion on a first connection line and a ground, the first connection changer connecting and disconnecting between the portion and the ground;
- and
- a first resistor interposed on a second connection line between the gate and a source of the FET, wherein the first connection line connects a gate of the FET and a gate drive voltage supply source, and
- wherein the protection circuit does not include a zener diode, and protects from overvoltage generated by the load upon discontinuing power to the load.
A protection circuit, to be provided for a circuit arrangement having an inductive load and an IGBT provided upstream of the load with respect to a flow of power current, the IGBT controlling an energization state of the load, the protection circuit comprising:
- a connection changer interposed on a connection line between a gate of the IGBT and a gate drive voltage supply source, the connection changer changing a connection state between a first connection state in which the gate is connected to the gate drive voltage supply and a second connection state in which the gate is connected to a ground;
- and
- a first resistor interposed between the gate and an emitter of the IGBT,
- wherein the protection circuit does not include a zener diode, and protects from overvoltage generated by the load upon discontinuing power to the load.
A protection circuit, to be provided for a circuit arrangement having an inductive load and an IGBT provided upstream of the load with respect to a flow of power current, the IGBT controlling an energization state of the load, the protection circuit comprising:
- a connection changer interposed between a portion on a connection line and a ground, the connection changer connecting and disconnecting between the portion and the ground;
- and
- a first resistor interposed between the gate and an emitter of the IGBT;
- wherein the connection line connects a gate of the IGBT and a gate drive voltage supply source, and
- wherein the protection circuit does not include a zener diode, and protects from overvoltage generated by the load upon discontinuing power to the load.
Dependencies are inferred from the claim text.