Mitsubishi Electric Corporation

Hisashi Oda

Shinji Sakai

Hisashi Kawafuji

Maki Hasegawa

Naoki Ikeda

A power semiconductor device of the present disclosure includes: a first switching element; a second switching element connected in parallel to the first switching element, and having a higher short circuit capability than the first switching element; drive circuits to drive the first switching element and the second switching element; and determination circuits to compare a target current as a sum of a current flowing through the first switching element and a current flowing through the second switching element to a first threshold and a second threshold greater than the first threshold. The drive circuits switch off the first switching element when the determination circuits determine that the target current is equal to or greater than the first threshold, and switch off the second switching element when the determination circuits determine that the target current is equal to or greater than the second threshold.

Power semiconductor device

The present technique relates to a protection circuit for a MOSFET and a protection circuit system including the protection circuit all of which can reduce losses in the main current and increase in the manufacturing costs for ensuring a sense area. The protection circuit includes: a first MOSFET for power through which a main current flows; an IGBT which is connected in parallel to the first MOSFET and through which a current diverted from the main current flows; a sense resistor connected in series with the IGBT; and a first control circuit that controls a gate voltage of the first MOSFET based on a value of a voltage to be applied to the sense resistor, wherein a ratio of the diverted current flowing through the IGBT to the main current flowing through the first MOSFET in current value ranges from 0.018% to 0.022%.

Protection circuit and protection circuit system

An inverter driver includes: a switching device; a drive circuit driving the switching device; a current detection device generating a voltage signal corresponding to a current flowing through the switching device; a noise filter removing noise superposed on the voltage signal; an excess current detection circuit outputting an excess current detection signal when the voltage signal input via the noise filter exceeds a first threshold value; and a short circuit detection circuit outputting an error signal when the excess current detection signal is input or the voltage signal input by bypassing the noise filter exceeds a second threshold value.

Inverter driver

A power module includes one control IC and a plurality of reverse conducting insulated gate bipolar transistors (RC-IGBTs). The control IC has the functions of a high-voltage IC and a low-voltage IC. The plurality of RC-IGBTs are disposed on three of four sides of the control IC and connected to the control IC through only wires.

Method for manufacturing power module

A control circuit includes an inverter circuit including a high-side MOSFET and a low-side MOSFET connected to form a totem-pole, a first gate driver configured to switch the low-side MOSFET, a second gate driver configured to switch the high-side MOSFET, a bootstrap circuit configured to supply a voltage to the second gate driver, and a detection section configured to issue an anomaly signal when a current larger than a predetermined value flows in the inverter circuit. In response to the issuing of the anomaly signal, the low-side MOSFET is turned off, and the high-side MOSFET is turned off. After that, in a state in which a freewheeling current is flowing through the low-side MOSFET, the low-side MOSFET is turned on to prevent a bootstrap capacitor of the bootstrap circuit from being overcharged.

Control circuit

A high-side gate drive circuit includes pulse generating circuits that generate a first pulse synchronized with an input signal, and level shift circuits that shift a level of a reference voltage for the first pulse to a power supply voltage of a high-side switching element. The level shift circuits include MOSFETs to be driven by the first pulse. The high-side gate drive circuit includes a mask signal generating circuit that generates a mask signal that becomes a high level in a period in which source potential of the MOSFETs becomes a high level, and reshot circuits that input, when the first pulse is input into the level shift circuits during a mask period that is a period in which the mask signal is a high level, a second pulse into the level shift circuits after the mask period.

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Tokyo, Japan

Hisashi Oda