公开(公告)号：US11411493B2

公开(公告)日：2022-08-09

申请号：US17319728

申请日：2021-05-13

Applicant: Richtek Technology Corporation

Inventor： Kuo-Chi Liu ,  Ta-Yung Yang ,  Chung-Lung Pai

IPC: H02M3/07 ,  G06F1/26 ,  H02M1/08

Abstract: A two-stage power converter includes: a resonant switched-capacitor converter (RSCC) receiving an input voltage and generating a first stage voltage; a voltage regulator receiving the first stage voltage and generating an output voltage; and a communication interface and control circuit generating a charging operation signal, at least one discharging operation signal and a switching signal. The charging operation signal and the discharging operation signal are employed to control the RSCC to perform a charging process and at least one discharging process respectively, and the switching signal is employed to control the voltage regulator, so as to synchronize a resonant frequency of the RSCC and a switching frequency of the voltage regulator. The communication interface and control circuit adjusts a delay interval after the discharging process ends, and starts the charging process at an end time point of the delay interval.

公开(公告)号：US11411489B2

公开(公告)日：2022-08-09

申请号：US17341074

申请日：2021-06-07

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Ta-Yung Yang ,  Kun-Yu Lin ,  Yu-Chang Chen

IPC: H02M3/00 ,  H02M3/335 ,  H02M1/08 ,  H02M1/38

Abstract: A resonant half-bridge flyback power converter includes: a power transformer and a resonant capacitor which are coupled in series between a half-bridge power stage and an output power; and a primary controller circuit controlling a high side power switch and a low side power switch of the half-bridge power stage. When the high side switch is OFF, the control signal of the low side power switch includes a resonant switching pulse for achieving resonant switching of the low side switch and a soft switching pulse for achieving ZVS of the high side switch. When the output power is lower than a delay threshold, the primary controller circuit determines a delay period which is between the resonant switching pulse and the soft switching pulse to control both the high side power switch and the low side power switch to be OFF. The delay period is negatively correlated with the output power.

公开(公告)号：US20220223464A1

公开(公告)日：2022-07-14

申请号：US17547829

申请日：2021-12-10

Applicant: Richtek Technology Corporation

Inventor： Kun-Huang Yu ,  Chien-Yu Chen ,  Ting-Wei Liao ,  Chih-Wen Hsiung ,  Chun-Lung Chang ,  Kuo-Chin Chiu ,  Wu-Te Weng ,  Chien-Wei Chiu ,  Yong-Zhong Hu ,  Ta-Yung Yang

IPC: H01L21/762 ,  H01L29/06 ,  H01L29/423 ,  H01L29/78

Abstract: A high voltage device includes: a semiconductor layer, a well, a bulk region, a gate, a source, and a drain. The bulk region is formed in the semiconductor layer and contacts the well region along a channel direction. A portion of the bulk region is vertically below and in contact with the gate, to provide an inversion region of the high voltage device when the high voltage device is in conductive operation. A portion of the well lies between the bulk region and the drain, to separate the bulk region from the drain. A first concentration peak region of an impurities doping profile of the bulk region is vertically below and in contact with the source. A concentration of a second conductivity type impurities of the first concentration peak region is higher than that of other regions in the bulk region.

公开(公告)号：US20220181987A1

公开(公告)日：2022-06-09

申请号：US17534538

申请日：2021-11-24

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Ta-Yung Yang ,  Wei-Hsu Chang ,  Yu-Chang Chen ,  Tsung-Wei Huang ,  Shui-Mu Lin

IPC: H02M3/335 ,  H02M1/08

Abstract: A control circuit for controlling a power supply circuit to provide power to a system device which includes a communication circuit includes: a pulse width modulation (PWM) controller configured to switch a transformer of the power supply circuit to generate a first output voltage; and a switched capacitor converter configured to generate a second output voltage according to the first output voltage. The second output voltage provides power to the communication circuit, wherein the communication circuit generates a power saving signal to control the PWM controller and the switched capacitor converter. When the power saving signal is enabled, the first output voltage is decreased and a duty ratio of the switched capacitor converter is increased.

公开(公告)号：US20220166324A1

公开(公告)日：2022-05-26

申请号：US17520635

申请日：2021-11-06

Applicant: Richtek Technology Corporation

Inventor： Kuo-Chi Liu ,  Ta-Yung Yang ,  Chung-Lung Pai

IPC: H02M3/158 ,  H02M3/00 ,  H02M3/07 ,  H02M1/00 ,  H02M1/36

Abstract: A resonant switching power converter includes: a power stage circuit and a driving circuit. The power stage circuit includes: a resonant capacitor, a resonant inductor and switches. The driving circuit includes: drivers for driving the switches; and a power supply circuit for providing driving powers to the drivers. The power supply circuit includes: a voltage booster circuit generating a booster power supply according to a clock signal, a DC voltage and an output related signal; driving capacitors, wherein a voltage across each driving capacitor corresponds to one driving power; and supply diodes, which are coupled in series from the booster power supply along a forward direction of the supply diodes. A backward end of each supply diode is coupled to a positive end of one corresponding driving power, to charge one corresponding driving capacitor, thus generating the corresponding driving power.

公开(公告)号：US20210408921A1

公开(公告)日：2021-12-30

申请号：US17341074

申请日：2021-06-07

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Ta-Yung Yang ,  Kun-Yu Lin ,  Yu-Chang Chen

IPC: H02M3/335 ,  H02M1/38 ,  H02M1/08 ,  H02M1/00

Abstract: A resonant half-bridge flyback power converter includes: a power transformer and a resonant capacitor which are coupled in series between a half-bridge power stage and an output power; and a primary controller circuit controlling a high side power switch and a low side power switch of the half-bridge power stage. When the high side switch is OFF, the control signal of the low side power switch includes a resonant switching pulse for achieving resonant switching of the low side switch and a soft switching pulse for achieving ZVS of the high side switch. When the output power is lower than a delay threshold, the primary controller circuit determines a delay period which is between the resonant switching pulse and the soft switching pulse to control both the high side power switch and the low side power switch to be OFF. The delay period is negatively correlated with the output power.

公开(公告)号：US11139744B2

公开(公告)日：2021-10-05

申请号：US16888923

申请日：2020-06-01

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Wei-Hsu Chang ,  Ta-Yung Yang ,  Yu-Chang Chen ,  Chao-Chi Chen ,  Chuh-Ching Li ,  Li-Di Lo ,  Hao-Wen Chung

IPC: H02M3/335 ,  G01R19/165 ,  H03M1/12 ,  H02M1/00

Abstract: A flyback power converter includes a primary side controller circuit for controlling a primary side switch; and a secondary side controller circuit for generating an SR (Synchronous Rectification) signal to control an SR switch. The SR signal includes an SR pulse and a ZVS (Zero Voltage Switching) pulse. The SR pulse controls the SR switch for synchronous rectification at the secondary side. The secondary side controller circuit samples and holds a voltage at a first end of the SR switch as a first voltage at a timing between the end of the ZVS pulse and the beginning of the SR pulse, and determines a length of the ZVS pulse so as to control the SR switch to be conductive for a ZVS time period, whereby the primary side switch achieves ZVS. The first voltage is proportional to an input voltage.

公开(公告)号：US20210126543A1

公开(公告)日：2021-04-29

申请号：US16879692

申请日：2020-05-20

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Wei-Hsu Chang ,  Ta-Yung Yang ,  Yu-Chang Chen ,  Chao-Chi Chen ,  Chuh-Ching Li ,  Li-Di Lo ,  Hao-Wen Chung

IPC: H02M3/335 ,  H02M1/08

Abstract: A switching controller circuit for controlling a flyback power converter includes: a power transformer, a primary side controller circuit and a secondary side controller circuit. The power transformer is coupled between the input voltage and the output voltage in an isolated manner. The primary side controller circuit controls a primary side switch of the flyback power converter. The secondary side controller circuit generates a synchronous rectification (SR) signal, to control an SR switch of the flyback power converter. The SR signal includes an SR pulse and a soft switching (SS) pulse. The SR pulse controls the SR switch to be ON for an SR period, to achieve synchronous rectification at the secondary side. The SS pulse controls the SR switch to be ON for an SS period, to achieve soft switching of the primary side switch.

公开(公告)号：US10566893B2

公开(公告)日：2020-02-18

申请号：US16134906

申请日：2018-09-18

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Ta-Yung Yang ,  Tzu-Chen Lin ,  Li-Di Luo ,  Pei-Sheng Tsu

IPC: H02M3/335 ,  H02M1/08 ,  H02M1/00

Abstract: A ZVS (zero voltage switching) control circuit for use in a flyback power converter includes a primary side controller circuit, a secondary side controller circuit, and a pulse transformer. In one switching cycle, a synchronous rectifier transistor is turned ON twice to generate a circulation current at the primary side winding, and after the synchronous rectifier transistor is turned OFF, the power transistor is turned ON for zero voltage switching. A synchronous signal coupled between the primary side and the secondary side is employed to synchronize the power transistor and the synchronous transistor. The synchronous signal also triggers an SR-ZVS pulse to turn ON the synchronous rectifier transistor for achieving the zero voltage switching when the power transistor is turned ON.

公开(公告)号：US20200036280A1

公开(公告)日：2020-01-30

申请号：US16247520

申请日：2019-01-14

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Ta-Yung Yang ,  Tzu-Chen Lin ,  Chien-Fu Tang

IPC: H02M1/08 ,  H02M3/335

Abstract: A ZVS (zero voltage switching) control circuit for use in a flyback power converter includes a primary side controller and a secondary side controller. The primary side controller generates a switching signal to control a power transformer through a power transistor to generate an output voltage. The secondary side controller generates an SR (synchronous rectifier) signal to control an SR transistor at a secondary side of the power transformer. The SR signal includes an SR-control pulse and a ZVS pulse. The SR-control pulse controls the SR transistor according to a demagnetizing period of the power transformer. The ZVS pulse determines the starting timing of the switching signal to achieve zero voltage switching for the power transistor. The secondary side controller generates the ZVS pulse after a delay time from when the power transformer is demagnetized. The delay time is determined according to an output load of the output voltage.