Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Hiroshi Nakatake

Yasushi Nakayama

Shinichi Kinouchi

Yoshiko Obiraki

Yuji Miyazaki

Tatsuya Kitamura

Akihiko Iwata

Akihiko Furukawa

Masayuki Imaizumi

Tatsuya Okuda

Takeshi Oi

Takayoshi Miki

Takeshi Horiguchi

Yoshikazu Tsunoda

Satoshi Ishibashi

Masaru Fuku

Toshiyuki Kikunaga

Takuya Sakai

Yuji Ebiike

Kosuke Nakano

Shinsuke Idenoue

Shizuri Tamura

Keisuke Iwasawa

Masashi Kaneko

A driving circuit including: a voltage detector that detects the sum voltage of a positive bias voltage and a negative bias voltage, the negative bias voltage or the positive bias voltage; and a switching element that is connected to the control terminal of a power element and the negative side of a negative-voltage power supply; wherein, when the value of the detection target voltage becomes lower than a voltage setting value or when a voltage between the control terminal and the reference terminal in the power element increases in a state where the value of the detection target voltage is lower than the voltage setting value, the voltage detector turns on the switching element to thereby supply, between the above terminals in the power element, a voltage of 0V or lower.

Power semiconductor element driving circuit

A power semiconductor module capable of reducing variation of inductance between upper/lower arms and reducing variation of current caused by the variation of inductance. The power semiconductor module includes circuit blocks (upper/lower arms) each of which is configured by connecting self-arc-extinguishing type semiconductor elements in series; a positive electrode terminal, a negative electrode terminal, and an AC terminal that are connected to each of the circuit blocks; and wiring patterns that connect the self-arc-extinguishing type semiconductor elements of the circuit blocks to the positive electrode terminal, the negative electrode terminal, and the AC terminal, wherein the circuit block is plural in number; the positive electrode terminal, the negative electrode terminal, and the AC terminal are each disposed to be plural in number corresponding to the circuit blocks; and the positive electrode terminals and the negative electrode terminals are closely disposed.

Power semiconductor module and power conversion device

A power semiconductor module capable of reducing variation of inductance between upper/lower arms and reducing variation of current caused by the variation of inductance. The power semiconductor module includes circuit blocks (upper/lower arms) each of which is configured by connecting self-arc-extinguishing type semiconductor elements in series; first and second positive electrode terminals, first and second negative electrode terminals, and first and second AC terminals. Further, there are first and second wiring patterns that connect the self-arc-extinguishing type semiconductor elements to the DC and AC terminals. The outline of the power semiconductor module has a substantially quadrangular surface.

A temperature detection circuit for detecting a temperature of a switching element, a current source for causing a forward current to flow to the temperature detection circuit, an amplifier circuit for amplifying a forward voltage of the temperature detection circuit, a current adjustment circuit for adjusting a magnitude of a gate current to the switching element on the basis of an output voltage of the amplifier circuit, and a drive circuit for receiving an external signal and turning ON/OFF the switching element, are included. The magnitude of the gate current caused to flow from the current adjustment circuit to the gate electrode of the switching element is adjusted on the basis of a change in a magnitude of the forward voltage corresponding to a change in the temperature of the temperature detection circuit.

Gate driving circuit including a temperature detection circuit for reducing switching loss and switching noise

A gate drive circuit for driving an IGBT serving as a power semiconductor device includes a constant-current gate drive circuit that charges a gate capacity of the IGBT at a constant current, and a constant-voltage gate drive circuit that is connected in parallel to the constant-current gate drive circuit between input and output terminals thereof via a series circuit constituted by a MOSFET and a resistor, and charges the gate capacity of the IGBT at a constant voltage, wherein the gate drive circuit charges the gate capacity of the IGBT using both the constant-current gate drive circuit and the constant-voltage gate drive circuit at the time of driving the IGBT.

Gate drive circuit

In a semiconductor device utilizing a power semiconductor element provided with a main cell and a current sensing cell, a load overcurrent is accurately detected and a short circuit current is rapidly detected. The output of a current sensing cell is connected to an inverting input terminal of an operational amplifier, and a non-inverting input terminal of the operational amplifier is connected to the source of the main cell. A current/voltage conversion circuit configured with the operational amplifier and a sensing resistor converts an output current of the current sensing cell into a sensing voltage. A first error detection circuit compares the sensing voltage with a first reference voltage and outputs an error signal. A second error detection circuit compares a voltage at the inverting input terminal of the operational amplifier with a second reference voltage set to be higher than a source-bias voltage and outputs an error signal.

Semiconductor device and error detector

A semiconductor device capable of rapidly and accurately sensing the information regarding the temperature of a semiconductor transistor contained therein. A MOSFET includes a plurality of cells, and includes a main cell group including a cell for supplying a current to a load among the plurality of cells, and a sense cell group including a cell for sensing temperature information regarding the temperature of the MOSFET thereamong. The main cell group and the sense cell group have different temperature characteristics showing changes in electrical characteristics to changes in temperature. A temperature sensing circuit senses the temperature of the MOSFET based on, for example, a value of a main current flowing through the main cell group and a value of a sense current flowing through the sense cell group.

Semiconductor device

A gate driving circuit for driving a voltage-driven switching device is provided with a current limiting circuit for limiting a gate current ig that flows into a gate terminal through a gate resistor at turn-on to a current limit value IL which defines an upper limit value. The current limit value IL is set at a value which is larger than a gate current value Iat turn-on of the switching device during a period when the Miller effect occurs but is smaller than a gate current value Iat a point in time when a main current begins to flow at turn-on in a case where the gate current ig is not limited by the current limiting circuit. This arrangement makes a variation in a collector current of the switching device moderate at turn-on thereof when the collector current begins to flow, thereby reducing high-frequency noise.

Gate driving circuit

A gate drive circuit capable of turning on a semiconductor switching element at high speed, which includes: a buffer circuit including a turn-on-drive switching element and a turn-off-drive switching element that are complementarily turned on and off, for driving the semiconductor switching element; a first DC voltage supply including a positive electrode connected to the source or emitter of the turn-on-drive switching element and a negative electrode connected to a reference potential; and a second DC voltage supply including a positive electrode connected to the source or emitter of the turn-off-drive switching element and a negative electrode connected to the reference potential.

To obtain a gate driving circuit in which rising of a constant current of a constant current circuit is fast and power saving is achieved, the gate driving circuit includes: a constant current driving circuit () for supplying a constant current; a gate terminal of a power semiconductor element (), which is connected to an output terminal of the constant current driving circuit; a comparator () for comparing a voltage at the gate terminal with a predetermined voltage value and outputting a signal indicating that the voltage is higher than the predetermined voltage value; and a driving control section () for increasing a current from the constant current driving circuit in response to a signal for turning on the power semiconductor element, and reducing the current from the constant current driving circuit in response to the signal from the comparator.

A drive circuit wherein any abnormality of a semiconductor element is prevented from being erroneously sensed in a case where a gate 'ON' command has entered in a state in which a gate voltage of the semiconductor element has not lowered fully. A detection process for a controlled variable of the semiconductor element is permitted only within a period which corresponds to a controlled variable of the semiconductor element at the time when an 'ON' signal has been inputted to a control circuit, and a detected controlled variable which is detected within the period and a comparison controlled variable which is set in correspondence with the controlled variable are compared so as to output an abnormality signal, whereby the semiconductor element is turn-off at a speed lower than in normal turn-off.

Drive circuit for semiconductor element

In semiconductor equipment, a switching timing adjuster is provided between insulated gate bipolar transistors and a control signal generator. The switching timing adjuster includes an input decision circuit that decides whether a signal output from the overvoltage protector is a signal that has been output due to a deviation in the switching timing at a turn-off or turn-on time, a signal holding circuit that holds a signal that is output from the input decision circuit, and a pulse formation circuit that forms a corrected switching control signal based on a signal held in the signal holding circuit and a switching control signal from the control signal generator.

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Tokyo, Japan

Hiroshi Nakatake