Renesas Electronics Corporation

Mitsubishi Denki Kabushiki Kaisha

Renesas Technology Corp.

Jtekt Corporation

Other

Masashi Oki

Kenichi Kozuka

Masato Oda

Akira Yamada

Hiromasa Suzuki

Toshiyuki Hiraki

Tadashi Kawahara

Kazuhiro Okamoto

Kenichiro Ohara

A rotation detection device includes a rotation detection circuit, a step-up power supply circuit, a step-down power supply circuit, a first power supply path, and a second power supply path. The rotation detection circuit is configured to detect a rotation number of a motor that generates a torque applied to a steering mechanism of a vehicle, based on an electric signal. The electric signal is generated according to a rotation angle of the motor that is acquired through an in-vehicle sensor.

Rotation detection device

A control circuit connected to a control device configured to control a motor connected to a rotation shaft that is convertible into a turning angle of a turning wheel, the control circuit includes a main circuit configured to calculates a rotation number indicating a rotational state of the rotation shaft based on a detection signal from a rotation angle sensor configured to detect a rotation angle of the motor as a relative angle, a detection result communication unit configured to detect whether or not there is an abnormality in the main circuit and output a detection result to the control device, and a pseudo abnormality generating unit configured to set the detection result to be abnormal based on a pseudo abnormal signal from the control device.

Control circuit and motor control device

An abnormal rise of oscillation frequencies of PLL circuits in conventional semiconductor devices has been an inevitable problem. This semiconductor device includes a phase difference detection circuit, a loop filter, and a voltage controlled oscillator that outputs an output clock signal. The voltage controlled oscillator includes a voltage-current converter that generates a control current having a current value in accordance with the voltage level of a frequency control voltage, an oscillator that varies the frequency of the output clock signal in accordance with the current value of the control current, and a current limiter that limits the current flowing in the oscillator in accordance with a limiting voltage transmitted through a signal-flow path provided independently from the other circuits.

Semiconductor device and control system

A class D amplifier defines different sets of resampled points A and B for channels chA and chB of an input digital audio signal, extracts an interpolation signal of the digital audio signal at the resampled points A and another interpolation signal of the digital audio signal at the resampled points B, and makes a correction to the phase of at least one of the interpolation signals. Thereby, radiation noise can be reduced even if the number of channels of the digital audio signal increases.

Signal processing device and class D amplifier that can reduce radiation noise even if the number of channels of a digital audio signal inputted thereto increases

A digital-to-analog (DA) converter includes a detector for detecting an input sampling frequency of digital data using a sampling clock and a master clock, an oversampling digital filter for oversampling the digital data on the basis of the input sampling frequency, an input sampling frequency change detector for detecting a change in the input sampling frequency, and a mute control for muting the data to be DA-converted on the basis of the detection result of the input sampling frequency change detector.

Digital-to-analog converter with sampling frequency detector

A circuit for amplifying and outputting a pulse width modulated (PWM) signal corresponding to an input audio signal with at least one output transistor and at least one protection control circuit. The protection control circuit compares a detected voltage and a threshold voltage. The detection voltage is a potential difference between a source and a drain of the output transistor. When the detection voltage exceeds the threshold voltage, the protection control circuit outputs a short circuit detection signal to the gate of the output transistor. As a result, the output transistor is turned OFF.

Circuit for amplifying and outputting audio signals

A clock-supply control system has an AND circuit whereby, when a transfer halt signal and a processing completion signal output by a DSP as well as a transfer halt signal output by a data output unit are all activated, the supply of a clock signal to the DSP is cut off.

Clock-supply control system of digital-signal processors

When a signal indicating a transition state from a synchronized state to an asynchronous state is outputted from a synchronous state register 8, data '0' generated by a '0' generating circuit 20 are stored in a data memory 10 instead of an output of an audio signal generating circuit 6, thus initializing the data memory 10 in advance. In a conventional coded-signal decoding circuit, when a transition was made from a synchronized state to an asynchronous state after failing to establish synchronization, the data memory 10 had to be initialized at a point in time before starting the next synchronous detection, presenting a problem in terms of time. To achieve this, a synchronous control method, a synchronous detecting circuit, and a synchronous detection method are provided.

Growing community of inventors

Tokyo, Japan

Masashi Oki