Semiconductor switch circuit

Patent metadata

Field	Value
Publication number	US-9680464-B2
Application number	US-201414785783-A
Country	US
Kind code	B2
Filing date	Mar 26, 2014
Priority date	Jul 24, 2013
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

A semiconductor switch circuit includes a plurality of switching units connected in series between a high-voltage node and a low-voltage node, and a plurality of diodes provided in association with the plurality of switching units, respectively. Respective cathodes of the plurality of diodes are connected to the plurality of switching units, respectively, and the anode of the diode associated with the switching unit connected to the low-voltage node receives a predetermined power supply voltage. Each switching unit includes a semiconductor switching device, a gate drive circuit driving the semiconductor switching device, and a DC-DC converter receiving a DC voltage from a cathode of the associated diode and supplying drive power to the gate drive circuit.

First claim

The invention claimed is:

1. A semiconductor switch circuit, comprising:
first to N-th (N is an integer of 2 or more) switching units connected in series between a high-voltage node and a low-voltage node;
first to N-th rectifying devices provided in association with said first to N-th switching units, respectively, and said first to N-th rectifying devices are connected in series; and
a DC power supply outputting a predetermined DC voltage, N being an integer of 2 or more, wherein
respective cathodes of said first to N-th rectifying devices are connected to said first to N-th switching units, respectively,
respective anodes of said first to (N−1)-th rectifying devices are connected to respective cathodes of said second to N-th rectifying devices, respectively,
an anode of said N-th rectifying device is connected to a positive electrode of said DC power supply and receiving said predetermined DC voltage,
a negative electrode of said DC power supply is connected to said low-voltage node,
a voltage value of said high-voltage node is higher than a voltage value of said low-voltage node,
each of said first to N-th switching units includes:
a semiconductor switching device;
a gate drive circuit to drive said semiconductor switching device; and
a DC-DC converter to receive a DC voltage from the cathode of an associated rectifying device and supply drive power to said gate drive circuit, and

said N semiconductor switching devices included respectively in said first to N-th switching units are connected in series between said high-voltage node and said low-voltage node.

2. The semiconductor switch circuit according to claim 1 , wherein respective output voltages of said DC-DC converters of said first to N-th switching units have the same values.

3. The semiconductor switch circuit according to claim 1 , wherein
said first to N-th switching units each further include an input capacitor, and
said input capacitors of said first to N-th switching units have respective one terminals connected to respective cathodes of said first to N-th rectifying devices, respectively, and have respective other terminals connected to respective electrodes, associated with said low-voltage node, of said semiconductor switching devices of said first to N-th switching units, respectively.

4. The semiconductor switch circuit according to claim 3 , wherein respective breakdown voltage values of said input capacitors of said first to (N−1)-th switching units are smaller respectively than respective breakdown voltage values of said input capacitors of said second to N-th switching units.

5. The semiconductor switch circuit according to claim 1 , wherein respective input voltage values of said DC-DC converters of said first to (N−1)-th switching units are smaller respectively than respective input voltage values of said DC-DC converters of said second to N-th switching units.

6. The semiconductor switch circuit according to claim 1 , wherein said semiconductor switching device is formed of a semiconductor having a value of a band gap larger than a value of a band gap of silicon.

7. The semiconductor switch circuit according to claim 1 , wherein
said semiconductor switching devices of said N-th to first switching units in non-conductive state are successively made conductive one by one by being driven by said gate drive circuits, and
said semiconductor switching devices of said N-th to first switching units in conductive state are simultaneously made non-conductive by said gate drive circuits.

8. The semiconductor switch circuit according to claim 1 , wherein said first to N-th rectifying devices each include one diode or a plurality of diodes connected in series.

Assignees

• Mitsubishi Electric Corp

Inventors

• Iwabuki Hiroyasu
• Tanaka Kazufumi

Classifications

• H03K17/74

  by the use, as active elements, of diodes (by the use of more than one type of semiconductor device H03K17/567; by the use of tunnel diodes H03K17/58; by the use of negative resistance diodes H03K17/70) · CPC title

• H01H33/59

  Circuit arrangements not adapted to a particular application of the switch and not otherwise provided for, e.g. for ensuring operation of the switch at a predetermined point in the AC cycle · CPC title

• H03K17/687

  the devices being field-effect transistors · CPC title

• H03K17/107

  in composite switches · CPC title

• H01H9/541 Primary

  Contacts shunted by semiconductor devices · CPC title