Richtek Technology Corporation

Chung Yuan Christian University

Shao-Hung Lu

Isaac Y Chen

An-Tung Chen

Yueh-Ming Chen

Jing-Meng Liu

Chien-Fu Tang

Tzu-Chen Lin

Chien-Yu Chen

Jian-Rong Huang

Jyun-Che Ho

Jo-Yu Wang

Ching-Jan Chen

Ting-Wei Liao

Kang-Ping Lin

Tsung-Hsi Yang

Mei-Fen Chen

Cheng-Kuang Lin

Nai-Yuan Liang

Yue-Hung Tang

Cheng Lun Tsai

Li Lin

Wei-Haur Chan

A reference voltage generator circuit includes: a first transistor and a second transistor, wherein the first transistor and the second transistor are coupled with each other and are located on a substrate, wherein the first transistor has a first conduction threshold voltage and a first rated voltage, wherein the second transistor has a second conduction threshold voltage and a second rated voltage, wherein the first rated voltage is higher than the second rated voltage; wherein the reference voltage generator circuit is configured to generate a bandgap reference voltage with temperature compensation according to a difference between the first conduction threshold voltage and the second conduction threshold voltage.

Reference voltage generator circuit with reduced manufacturing steps

A topical subcutaneous microcirculation detection device includes a first light source module, a second light source module, a lens plate, a first light sensor, and a second light sensor. The first and second light source modules are configured to emit first and second illumination beams, respectively. A flat plate portion of the lens plate is disposed to lean against a first portion of skin of a subject. A convex surface of a first convex lens portion of the lens plate is disposed to push into a second portion of the skin of the subject. The first and second illumination beams are reflected into first and second reflected beams by the first and second portions of the skin, respectively. The first and second reflected beams are transmitted to the first and second light sensors, respectively.

Topical subcutaneous microcirculation detection device

A power converter control circuit includes a feedback circuit and a pulse width modulation signal generating circuit for configuring a power stage circuit to provide power to a load. The feedback circuit generates a first gain signal and a second gain signal according to an output voltage sensing signal coupled with the load. The feedback circuit further generates a feedback signal according to the first gain signal and the second gain signal. The pulse width modulation signal generating circuit configures the operation of the power stage circuit according to the feedback signal and a reference signal. Moreover, the feedback circuit and the pulse width modulation signal generating circuit are configured on the same integrated circuit package.

Power converter control circuit

The present invention discloses a power factor correction circuit, a control circuit therefor and a method for driving a power factor correction circuit. The power factor correction circuit receives rectified power obtained by rectifying AC power, and corrects the power factor thereof. The power factor correction circuit includes an inductor, and it generates a reference signal as a limit for the inductor current. The reference signal is proportional to Comp/Vin, wherein Comp is a signal relating to a feedback signal, and Vin is a voltage signal relating to the AC power or the rectified power.

Power factor correction circuit, control circuit therefor and method for driving load circuit through power factor correction

A feedback loop is used to optimize a zero current threshold for a switching regulator. After the low side power switch of the switching regulator turns off, the switching node state is monitored to adjust the zero current threshold in a real time and thus the low-side power switch is prevented from turning off too early or too late. Thereby the efficiency in green mode is optimized.

Real time adjustable zero current detection for a switching regulator

An adjustable driver voltage source for a switching power supply uses a linear regulator to provide a driver voltage, and a modulator to adjust the driver voltage according to the loading change of the switching power supply. The modulator may lower the driver voltage at light load to reduce the switching loss and thereby increase the power efficiency of the switching power supply.

Adjustable driver voltage source for a switching power supply and method for adjusting driver voltage in a switching power supply

For a system to avoid abnormal operation caused by a shorted parameter setting pin of an integrated circuit, a protection apparatus and method apply a buffered reference voltage to the parameter setting pin to define an internal parameter of the integrated circuit by the buffered reference voltage and an external element connected to the parameter setting pin, and detect the rapid variation of the internal parameter to trigger a shutdown signal or slow down the speed of the variation of the internal parameter reflected to an adjustable signal of the integrated circuit.

Protection to avoid abnormal operation caused by a shorted parameter setting pin of an integrated circuit

A multi-channel regulator system includes serially connected PWM integrated circuits, each of which determines a PWM signal for a respective channel to operate therewith, and individually controls its operation mode according to whether or not an external clock is detected. Therefore, each channel will not be limited to operate under a constant mode and could become a master channel or a slave channel. Additionally, each of the PWM integrated circuits generates a phase shifted synchronous clock for its next channel during it is enabled, and thus all the channels operate in a synchronous but phase interleaving manner.

Phase interleaving control method for a multi-channel regulator system

A frequency setting circuit and method for an integrated circuit detect the voltage at a pin of the integrated circuit during a frequency setting period, and determine a frequency setting signal according to the detected voltage to set the frequency of a clock provided by an oscillator in the integrated circuit. After setting the frequency, the frequency setting circuit and method store the frequency setting signal and stop detecting the voltage at the pin. Thus the pin can be used for other functions.

Frequency setting circuit and method for an integrated circuit

A mix mode wide range divider is provided for dividing a first signal by a second signal to generate an output signal. A third signal is generated depending on the resistance of a first adjustable resistor, and a fourth signal is generated according to the third signal and a target value determined by the second signal, to adjust the resistance of the first adjustable resistor and the resistance of a second adjustable resistor. The resistance of the first adjustable resistor is so adjusted to make the third signal equal to the target value, and the resistance of the second adjustable resistor is so adjusted to maintain a ratio of the resistance of the second adjustable resistor to the resistance of the first adjustable resistor. The output signal is generated depending on the first signal and the resistance of the second adjustable resistor.

Mix mode wide range divider and method thereof

A DrMOS combines a high side power MOSFET, a low side power MOSFET and a driver circuit for driving the power MOSFETs with current balance and thermal balance mechanism and variable phase control circuit on a single chip.

Multi-functional DrMOS

A mix mode wide range multiplier and method are provided for multiplying a first signal by a second signal to generate an output signal. A reference signal is generated according to a first gain and a reference value, the output signal is generated according to a second gain and the first signal, a target value is generated according to the second signal, the first gain is adjusted to make the reference signal equal to the target value, and the second gain is adjusted to maintain a ratio of the second gain to the first gain.

Growing community of inventors

Taoyuan, Taiwan

Shao-Hung Lu