Mitsubishi Electric Corporation

Mitushibhi Electric Corporation

Yukihiko Wada

Shota Morisaki

Hiroyuki Takagi

Yoshiko Tamada

Chihiro Kawahara

Yoshitaka Naka

A deteriorated section identifying unit refers to correspondence information that defines a deteriorated section of a plurality of bonding sections to the emitter electrode surface to which the first bonding wires are connected, for a combination of temporal change of a first voltage that is a difference between a potential at a collector main terminal and a potential at the emitter main terminal and temporal change of a second voltage that is a difference between a potential at the emitter reference terminal and a potential at the emitter main terminal, and identifies the deteriorated section corresponding to a combination of temporal change of the first voltage measured by a first voltage measuring circuit and temporal change of the second voltage measured by a second voltage measuring circuit.

Semiconductor device and power conversion device

A direct-current power supply applies a DC voltage to test semiconductor devices. A current detection unit detects a leakage current of a test circuit in which test semiconductor devices are included. A measuring instrument records a pulse waveform of the leakage current. An analyzer analyzes reliability of test semiconductor devices included in the test circuit based on the recorded pulse waveform.

Semiconductor device reliability evaluation apparatus and semiconductor device reliability evaluation method

In a short circuit protection circuit, a first gate resistor is connected between a first output node of a gate driver and a first gate terminal. A first real-time control circuit operates to decrease a potential of the first gate terminal when the first real-time control circuit detects that a short circuit current passes through a first semiconductor switching element. The operation monitoring circuit includes a differential voltage circuit configured to output a potential difference between a potential proportional to a potential difference across the first gate resistor and the potential of a first power supply. The operation monitoring circuit monitors, based on an output of the differential voltage circuit, whether the first real-time control circuit is in operation.

Short circuit protection circuit for semiconductor switching element

Turn-on and turn-off of a semiconductor device are controlled through control of a gate voltage in accordance with a driving control signal. At a first time after a start of a Miller period of a gate voltage in driving a gate of the semiconductor device in accordance with the driving control signal, a driving signal is changed from '1' to '0' to thereby make a gate driving ability temporarily lower than the gate driving ability during a period from a starting time of the turn-on operation to the first time. Further, at a second time corresponding to an end of the Miller period, the driving signal is changed from &#x201c;0&#x201d; to &#x201c;1&#x201d; to thereby increase the gate driving ability.

Semiconductor device driving method and driving apparatus and power conversion apparatus

A power switching apparatus includes a plurality of semiconductor switching devices connected in parallel with each other and a plurality of balance resistor units. The plurality of balance resistor units each have one end connected to a control electrode of an associated semiconductor switching device and the other end to which a common control signal is input. Each balance resistor unit is configured to have a resistance value switched between different values depending on whether the plurality of semiconductor switching devices are turned on or turned off in accordance with the control signal.

Growing community of inventors

Chiyoda-ku, Japan

Yukihiko Wada