Renesas Electronics Corporation

Nec Corporation

Renasas Electronics Corporation

Shunichi Kaeriyama

Masayuki Mizuno

Koichi Takeda

Hirokazu Nagase

Koichi Nose

Kouichi Yamaguchi

Shinichi Uchida

Kenji Nishikawa

Norio Kido

Toshinori Kiyohara

Masato Kanno

Mika Yonezawa

A semiconductor device includes a galvanic isolator; a transmitting circuit that transmits a transmission signal via the galvanic isolator; a receiving circuit that receives a received signal corresponding to the transmission signal via the galvanic isolator; an encoding circuit that encodes two input signals and generates the transmission signal; and a decoding circuit that decodes the two input signals from the received signals.

Semiconductor device and control system

A drive device comprises a sensor for detecting a state of stress applied to a power transistor, a threshold voltage setting circuit for outputting a threshold voltage, an anomaly monitor circuit for determining whether or not a state of stress is abnormal by comparing a detected voltage of the sensor with the threshold voltage, and a control circuit for fixing the power transistor to either on or off when the state of stress is determined to be abnormal by the anomaly monitor circuit. When an operating mode is a test mode, the control circuit tests whether the anomaly monitor circuit determines the state of the stress is abnormal or not by switching a level of the threshold voltage set by the threshold voltage setting circuit so as to determine that a state of the stress applied to the power transistor is abnormal in the normally operating anomaly monitor circuit.

Drive device, power supply system, and method of testing drive device

A power control circuit according to one embodiment includes an H-bridge circuit formed using a plurality of power transistors. The power transistors are respectively connected to current measurement circuits that measure currents flowing through the power transistors. Each of the power transistors includes a main emitter and a sense emitter through which a current corresponding to a current flowing through the main emitter flows. Each of the current measurement circuits measures a current flowing through each of the power transistors by using a current flowing through the sense emitter included in the power transistor. A control circuit controls the power transistors based on current values respectively measured by the current measurement circuits.

Power control circuit

There is to provide a power conversion device capable of estimating a junction temperature of a power transistor at a high accuracy. The control device includes a temperature estimation unit and controls the on and off of the power transistor through a driver. The voltage detection circuit detects the inter-terminal voltage of a source and drain terminals during the on-period of the power transistor. The temperature estimation unit previously holds the correlation information between the inter-terminal voltage and inter-terminal current of the source and drain terminals and the junction temperature, and estimates the junction temperature, based on the inter-terminal voltage detected by the voltage detection circuit, the known inter-terminal current, and the correlation information.

Power conversion device and semiconductor device

The semiconductor device according to one embodiment includes a power transistor and a sense transistor connected in parallel with each other, a first operational amplifier having a non-inverting input terminal connected to an emitter of the sense transistor and an inverting input terminal connected to an emitter of the power transistor, a resistor element having one end connected to the emitter of the sense transistor and another end connected to a first node, and an adjustment transistor placed between the first node and a low-voltage power supply. The first operational amplifier adjusts a current flowing through the adjustment transistor so that an emitter voltage of the power transistor and an emitter voltage of the sense transistor are substantially the same.

Semiconductor device

To provide a receiver, a communication device, and a communication method capable of restoring a signal transmitted via a non-contact transmission channel with high accuracy. A communication device has a transmission circuit that converts an input signal into a pulse, a non-contact transmission channel that has a primary side coil and a secondary side coil and transmits the pulse from the transmission circuit in a non-contact manner, a restoration circuit that restores the input signal on the basis of a reception signal corresponding to the pulse transmitted via the non-contact transmission channel, an initialization unit that initializes an output of the non-contact transmission channel, and an initialization control unit that outputs a control signal of controlling the initialization unit on the basis of the reception signal corresponding to the pulse received via the non-contact transmission channel.

Receiver, communication device, and communication method

The present invention provides a drive device and a power supply system capable of driving a power transistor with low power while reflecting variations in manufacture process and external environments. A trigger detection circuit monitors a voltage between terminals or a current between terminals in a switching period of a power transistor and detects that the voltage between terminals or the current between terminals reaches a predetermined reference value. A current switching circuit selects a register outputting a current value to a variable current driver circuit from a plurality of registers and switches the register to be selected using a detection result of the trigger detection circuit as a trigger in the switching period, thereby making the drive current of the variable current driver circuit shift.

Drive device and power supply system

Provided is a receiving circuit that operates in a power supply system different from a transmitting circuit outputting a transmission signal and receives the transmission signal through an AC coupling device where a primary coil through which the transmission signal flows and a secondary coil having a center tap to which a specified voltage is supplied from an external terminal are magnetically coupled, which includes a pulse width amplifier circuit that holds pulse signals appearing at both ends of the secondary coil for a specified period of time and outputs them as hold signals, respectively, and a differential amplifier that compares a voltage of the hold signal and a voltage of the hold signal and outputs a comparison result.

Receiving circuit and signal receiving method

An object of the invention is to improve precision of current detection in a switching system having plural switching circuits. A first PWM timing generation circuit generates an edge timing of a PWM signal by using a comparison value and a count value and drives a first switching circuit. A second PWM timing generation circuit generates an edge timing of a PWM signal of plural phases by using a comparison value and a count value and drives a second switching circuit. One of the switching circuits is an inverter circuit of a common shunt type in which a shunt resistor is provided commonly for plural phases. One of the PWM timing generation circuits shifts the generated edge timing so that an interval between an edge timing of one of the circuits and an AD conversion timing of the other becomes equal to or larger than a predetermined reference value.

Switching system

According to one aspect, a module_includes a communication circuitthat performs data communication with an externally-provided control devicethrough a communication bus, and an interrupt signal generation circuitthat, when an interrupt instruction signal Ioutput from the communication circuitbecomes an active state, generates an interrupt signal and outputs the generated interrupt signal to the communication bus, the interrupt signal being defined by using a bus potential undefined in a data communication standard.

Semiconductor device and control method thereof

The number of ICs used for a power converter is reduced. The power converter includes n power transistors each having an emitter terminal or a source terminal connected to a common line, and driver ICs. Each of the driver ICs includes n pre-drivers that drive the respective n power transistors, and a receiver circuit that is integrated monolithically with the n pre-drivers. The receiver circuit is coupled with a transmitter circuit by AC coupling, and outputs a control signal that controls the n pre-drivers in response to a signal received from the transmitter circuit.

Growing community of inventors

Tokyo, Japan

Shunichi Kaeriyama