Patents Assigned to Richtek Technology Corporation
  • Patent number: 11063148
    Abstract: A high voltage depletion mode MOS device with adjustable threshold voltage includes: a first conductive type well region; a second conductive type channel region, wherein when the channel region is not depleted, the MOS device is conductive, and when the channel region is depleted, the MOS device is non-conductive; a second conductive type connection region which contacts the channel region; a first conductive type gate, for controlling the conductive condition of the MOS device; a second conductive type lightly doped diffusion region formed under a spacer layer of the gate and contacting the channel region; a second type source region; and a second type drain region contacting the connection region but not contacting the gate; wherein the gate has a first conductive type doping or both a first and a second conductive type doping, and wherein a net doping concentration of the gate is determined by a threshold voltage target.
    Type: Grant
    Filed: March 1, 2018
    Date of Patent: July 13, 2021
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Tsung-Yi Huang, Ching-Yao Yang
  • Patent number: 11018597
    Abstract: A flyback power converter circuit includes: a transformer; a primary side switch, for controlling a primary winding to convert an input voltage to an output voltage and an internal voltage; a primary side control circuit, which is powered by the internal voltage; the primary side control circuit generates a switching signal according to a feedback signal, to operate the primary side switch; a secondary side control circuit, which generates the feedback signal according the output voltage; and a dummy load circuit, which is coupled to the output voltage, wherein when the output voltage drops to or is lower than a predetermined threshold, the dummy load circuit generates a dummy load current, to determine the feedback signal, so that the internal voltage is not undesirably low. When the output voltage exceeds the predetermined threshold, the dummy load circuit adjusts the dummy load current to zero current.
    Type: Grant
    Filed: February 6, 2020
    Date of Patent: May 25, 2021
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Ta-Yung Yang, Chao-Chi Chen, Chen-Hung Tsai, Chuh-Ching Li
  • Patent number: 10998404
    Abstract: A high voltage device includes: a semiconductor layer, an isolation structure, a first deep well, a second deep well, a drift well, a first well, a second well, a body region, a body contact, a high voltage well, a gate, and a source and a drain. The high voltage well is formed in the second deep well, and the high voltage well is not in contact with any of the first deep well, the first well, and the second well, wherein at least part of the high voltage well is located right below all of a drift region to suppress a latch-up current generated in the high voltage device.
    Type: Grant
    Filed: July 4, 2019
    Date of Patent: May 4, 2021
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventor: Tsung-Yi Huang
  • Patent number: 10980090
    Abstract: AN LED driving apparatus includes a power stage circuit and a dimming control circuit. The power stage circuit drives an LED circuit. The dimming control circuit includes a duty ratio conversion circuit, a digital-to analog conversion (DAC) circuit, an error amplifier (EA) circuit and a modulation control circuit. The duty ratio conversion circuit converts a PWM dimming signal to a digital duty ratio signal. The DAC circuit converts the digital duty ratio signal to an analog reference signal. The EA circuit generates an error amplified signal according to a difference between the analog reference signal and an output current related signal. The modulation control circuit generates a PWM control signal according to the error amplified signal, to control the power switch, such that the output current relates to a dimming duty ratio, whereby the dimming control circuit dims the LED circuit according to the PWM dimming signal.
    Type: Grant
    Filed: April 16, 2020
    Date of Patent: April 13, 2021
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Yu-Min Chen, Isaac Y. Chen, Leng-Nien Hsiu
  • Patent number: 10972090
    Abstract: An output stage circuit for transmitting data via a bus includes a high side switch, a high side diode structure, a high side clamp circuit, a low side switch, and a low side diode structure. An impedance circuit of the bus is coupled between the high side switch and the low side switch, for generating a differential output signal according to high and low side output signals. A high side N-type region of the high side diode structure encompasses a high side P-type region thereof, and a low side N-type region of the low side diode structure encompasses a low side P-type region thereof. The high side clamp circuit is connected to the high side N-type region in series, for clamping a voltage of the high side N-type region to be not lower than a predetermined voltage, to prevent a parasitic PNP bipolar junction transistor from being turned ON.
    Type: Grant
    Filed: August 3, 2020
    Date of Patent: April 6, 2021
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Yu-Wen Chang, Leng-Nien Hsiu, Isaac Y. Chen
  • Patent number: 10943978
    Abstract: An N-type high voltage device includes: a semiconductor layer, a well region, a floating region, a bias region, a body region, a body contact, a gate, a source and a drain. The floating region and the bias region both have P-type conductivity, and both are formed in a drift region in the well region. The bias region is electrically connected with a predetermined bias voltage, and the floating region is electrically floating, to increase a breakdown voltage of the high voltage device and to suppress turning-ON a parasitic transistor in the high voltage device.
    Type: Grant
    Filed: March 14, 2019
    Date of Patent: March 9, 2021
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventor: Tsung-Yi Huang
  • Patent number: 10944321
    Abstract: A multi-level switching power converter includes a multi-level power stage circuit which converts an input power to an output power. The power stage circuit includes an inductor, a conversion capacitor and plural power switches. The controller circuit controls the multi-level power stage circuit and includes: a feedback pulse generator circuit which generates a trigger pulse; a first timer circuit and a second timer circuit which determine a first time period and a second time period respectively according to the trigger pulse; and an adjusting circuit which adjusts the first time period according to a difference between the voltage across the conversion capacitor and a reference voltage such that an average of the voltage across the conversion capacitor is substantially equal to a level of the reference voltage.
    Type: Grant
    Filed: October 15, 2019
    Date of Patent: March 9, 2021
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Yung-Chun Chuang, Tsung-Wei Huang
  • Patent number: 10923589
    Abstract: A high voltage device includes: a crystalline silicon layer, a well, a body region, a gate, a source, and a drain. The body region has a P-type conductivity type, and is formed in the well. The gate is located on and in contact with the well. The source and the drain have an N-type conductivity type, and are located below, outside, and at different sides of the gate, and are located in the body region and the well respectively. An inverse region is defined in the body region between the source and the well, to serve as an inverse current channel in an ON operation. The inverse region includes a germanium distribution region which has a germanium atom concentration higher than 1*1013 atoms/cm2. Adrift region is defined in the well, between the body region and the drain, to serve as a drift current channel in an ON operation.
    Type: Grant
    Filed: August 15, 2019
    Date of Patent: February 16, 2021
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Tsung-Yi Huang, Kun-Huang Yu
  • Patent number: 10868115
    Abstract: A high voltage device includes: a semiconductor layer, an isolation region, a deep well, a buried layer, a first high voltage well, a first conductivity type well, a second high voltage well, a body region, a body contact, a deep well column, a gate, a source and a drain. The deep well column is located between the drain and a boundary of the conductive layer which is near the source in a channel direction. The deep well column is a minority carriers absorption channel, to avoid turning ON a parasitic transistor in the high voltage device.
    Type: Grant
    Filed: June 22, 2019
    Date of Patent: December 15, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Tsung-Yi Huang, Chu-Feng Chen
  • Patent number: 10840697
    Abstract: A power supply system includes a power supplier circuit and a power receiver circuit. The power supplier circuit supplies a power via a communication interface compatible with a first communication interface specification or a second communication interface specification. The first communication interface specification includes a delay threshold. After the power supplier circuit is coupled to the power receiver circuit, the power supplier circuit supplies the power after a first delay period. The power receiver circuit confirms whether the power supplier circuit is coupled to the power receiver circuit via a coupling confirmation step according to the first communication interface specification. The power receiver circuit confirms whether the power supplier circuit is compatible with the first communication interface specification or the second communication interface specification according to whether the first delay period is greater than the delay threshold.
    Type: Grant
    Filed: March 14, 2019
    Date of Patent: November 17, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Shung-Tsung Chen, Yi-Syue Jhu, Chieh-Min Lo, Tsung-Han Tsai
  • Patent number: 10823785
    Abstract: The invention relates to a method for estimating the state of charge (SOC) of a battery when battery is in the at least states of: charging, discharging, and relaxing. The invention makes use of the battery voltage (VBAT) instead of the battery current. In order to build models in the method, we use standard charging and discharging processes to collect battery information.
    Type: Grant
    Filed: August 15, 2017
    Date of Patent: November 3, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventor: Chang-Yu Ho
  • Patent number: 10819209
    Abstract: A multi-source energy harvester system includes a power conversion apparatus. First and second energy harvesters respectively harvest first and second energy and respectively provide first and second input powers. The power conversion apparatus includes an adjustable impedance matching circuit and a power conversion circuit. The impedance matching circuit generates an adjusted power according to the first input power. The power conversion circuit converts a bus power to an output power. The energy harvester system controls a first and a second switch circuits according to the adjusted power and/or the second input power to select and conduct one of the adjusted power or the second input power as the bus power, and adjusts an impedance of the adjustable impedance matching circuit to maximize a voltage of the adjusted power.
    Type: Grant
    Filed: May 17, 2019
    Date of Patent: October 27, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Kuo-Chi Liu, Chang-Yu Ho
  • Patent number: 10819166
    Abstract: A wireless power transfer system includes: a transmitting side, which includes a resonant transmitting circuit, the resonant transmitting circuit including a transmitter coil; and a receiving side, which includes a resonant receiving circuit, the resonant receiving circuit including a receiver coil for performing induction with the transmitter coil to generate a resonant receiver voltage, wherein the transmitter adjusts a transmitter current of the resonant transmitting circuit according to the resonant receiver voltage such that the resonant receiver voltage is regulated to a target voltage level. The wireless power transfer system determines a shift distance from a present relative position to an optimal relative position according to the adjusted transmitter current of the resonant transmitting circuit.
    Type: Grant
    Filed: September 6, 2018
    Date of Patent: October 27, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventor: Kuo-Chi Liu
  • Patent number: 10811962
    Abstract: A multi-level switching power converter includes a multi-level power stage circuit which converts an input power to an output power. The power stage circuit includes an inductor, a conversion capacitor and plural power switches. The controller circuit controls the multi-level power stage circuit and includes: a feedback pulse generator circuit which generates a trigger pulse; a first timer circuit and a second timer circuit which determine a first time period and a second time period respectively according to the trigger pulse; and an adjusting circuit which adjusts the first time period according to a difference between the voltage across the conversion capacitor and a reference voltage such that an average of the voltage across the conversion capacitor is substantially equal to a level of the reference voltage.
    Type: Grant
    Filed: November 12, 2019
    Date of Patent: October 20, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Yung-Chun Chuang, Tsung-Wei Huang
  • Patent number: 10811532
    Abstract: A high voltage device includes: a semiconductor layer, an isolation structure, a drift oxide region, a well, a body region, a body contact, a buffer region, a gate, and a source and a drain. The body contact includes a main body contact and at least one sub-body contact. The main body contact is adjacent to the source, wherein the main body contact and the source are rectangles that extend along a width direction, and the source is located between the main body contact and the gate. The sub-body contact extends from the main body contact toward the gate and contacts an inverse current channel. The buffer region encompasses all the periphery of the body region below a top surface of the semiconductor layer, wherein an impurity concentration of the buffer region is lower than an impurity concentration of the body region.
    Type: Grant
    Filed: March 13, 2019
    Date of Patent: October 20, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Tsung-Yi Huang, Chien-Yu Chen
  • Patent number: 10804883
    Abstract: A power supply apparatus having multiple output ports includes: a master power supply circuit for supplying a master output power via a master power switch; a slave power supply circuit for supplying a slave output power via a slave power switch; and a shared resistor coupled between a power management node and a reference ground level. The slave sensing circuit outputs the slave sensing current via a slave power management pin, to generate a total power signal at the power management node. The master control circuit senses the total power signal via the master power management pin, to determine an adjustment current. The slave control circuit controls the slave power switch according to a voltage at the slave power management pin, to adjust the slave output power, so that a total power of the master output power and the slave output power does not exceed a predetermined power range.
    Type: Grant
    Filed: October 10, 2019
    Date of Patent: October 13, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Isaac Y. Chen, Yi-Wei Lee
  • Patent number: 10797500
    Abstract: A charger circuit for providing a charging current and voltage to a battery includes a power delivery unit and a capacitive power conversion circuit. The power delivery unit converts an input power to a DC voltage and current. The capacitive power conversion circuit includes a conversion switch circuit including plural conversion switches and being coupled with one or plural conversion capacitors, a regulation switch, and a conversion control circuit. In a current scaled-up charging mode, the DC current is regulated, and the conversion control circuit controls the connection of the plural conversion capacitors such that the charging current is scaled-up of the DC current substantially by a predetermined current scale-up factor. In a constant voltage linear charging mode, the conversion control circuit linearly controls the regulation switch to regulate the level of the charging voltage to a predetermined constant voltage level.
    Type: Grant
    Filed: June 30, 2017
    Date of Patent: October 6, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Tsung-Wei Huang, Shun-Yu Huang
  • Patent number: 10741348
    Abstract: A power transmission apparatus includes a power delivery unit generating a power, a load unit receiving the power, a cable, at least a connector, at least a power switch, and a communication interface. The power delivery unit and the load unit is coupled by the connector and the cable, and the power is delivered through the cable and the connector. A voltage threshold is determined according to a delivery current of the power or a load current of the load unit. When a voltage difference between a delivery voltage of the power and a load voltage of the load unit is larger than the voltage threshold, the power switch is turned OFF, wherein information of one of the delivery voltage, the load voltage, the delivery current, and/or the load current is provided through the communication interface.
    Type: Grant
    Filed: January 15, 2018
    Date of Patent: August 11, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Wei-Hsu Chang, Ta-Yung Yang
  • Patent number: 10742072
    Abstract: A wireless power transmitter circuit includes a power converter circuit, a power inverter circuit, an LC circuit, a resonant transmitter circuit, and a control circuit. The LC circuit includes an inductor and a capacitor, wherein an reactance of the LC circuit is substantially zero. The LC circuit is for converting the AC output current to a coil current. The resonant transmitter circuit includes at least one transmitter coil and a variable capacitor circuit, wherein the coil current flows through the at least one transmitter coil to generate a resonant wireless power. The control circuit generates a capacitance adjustment signal for adjusting an impedance of the variable capacitor circuit, such that the resonant transmitter circuit substantially operates in an impedance matched condition.
    Type: Grant
    Filed: May 18, 2018
    Date of Patent: August 11, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Kuo-Chi Liu, Ke-Horng Chen
  • Patent number: 10714944
    Abstract: A charging circuit includes a power conversion circuit, an inductor, and at least one conversion capacitor. The power conversion circuit includes a conversion switch circuit and a conversion control circuit. The conversion switch circuit includes an upper switch, a lower switch, and at least one auxiliary switch. In a switching conversion mode, the conversion control circuit operates the conversion switch circuit to switch the inductor to plural voltage levels repetitively for converting an input power to a charging power to charge a battery by switching power conversion. In a capacitive conversion mode, the conversion control circuit operates the conversion switch circuit to switch the conversion capacitor between two of voltage division nodes periodically for converting the input power to the charging power by capacitive power conversion.
    Type: Grant
    Filed: October 22, 2018
    Date of Patent: July 14, 2020
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Wei-Jen Huang, Tsung-Han Lee, Shun-Yu Huang, Chun-Kai Chang