Richtek Technology Corporation

Jen-Hung Chi

Jo-Yu Wang

Wei-Hsu Chang

An-Tung Chen

Pei-Cheng Huang

Yen-Shin Lai

Kuo-Chung Lee

Shiue-Shr Jiang

Yu-Kuang Wu

Shiueshr Jiang

Chih-Chang Chen

The present invention provides a motor controller for controlling a DC motor according to a reference signal. The motor controller includes a compensator, a pulse width modulation unit, and a motor driving unit. The compensator generates a control signal according to the reference signal and a sensing signal from the DC motor. The pulse width modulation unit generates a motor control signal by comparing the control signal and a ramp signal having a varying frequency. The motor driving unit receives the motor control signal and drives the DC motor according to the motor control signal.

Motor controller

An auto-zero amplifier is disclosed, having an amplifying circuit, a switch, and a difference signal generating circuit. The amplifying circuit receives a first input signal for generating a first output signal, and receives a second input signal for generating a second output signal. The switch is coupled between the amplifying circuit and a capacitor. The switch is conducted for charging or discharging the capacitor to a voltage with the first output signal, and the switch is not conducted for keeping the capacitor at the voltage. The difference signal generating circuit is coupled with the amplifying circuit and the capacitor for generating a difference signal of the first output signal and the second output signal, a multiple of the difference signal, a part of the difference signal, and/or a digital output value for the difference signal.

Auto-zero amplifier and sensor module using same

A zero-crossing detection circuit and a commutation device using the zero-crossing detection circuit are provided. The zero-crossing detection circuit is adapted into a three-phase brushless DC (direct current) motor with first to third coils. One terminal of each of the first to third coils is electrically coupled together with each other. The detection circuit comprises a first selection circuit, a second selection circuit and a comparator. The first selection circuit and the second selection circuit are both electrically coupled to another terminals of the first to third coils, to obtain first to third terminal voltages, and output one of the first to third terminal voltages according to a selection signal. The comparator is configured for comparing an output of the first selection circuit and an output of the second selection circuit, to output a comparing result.

Zero-crossing detection circuit and commutation device using the zero-crossing detection circuit

Growing community of inventors

Taichung, Taiwan

Jen-Hung Chi