公开(公告)号：US09755530B2

公开(公告)日：2017-09-05

申请号：US15144610

申请日：2016-05-02

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Li-Di Luo ,  Yu-Kai Chen ,  Yu-Chang Chen

IPC: H02M3/315 ,  H02M3/335 ,  H02M1/08

CPC classification number: H02M3/33523 ,  H02M1/08 ,  H02M3/33592 ,  Y02B70/1475

Abstract: The present invention discloses a power converter with synchronous control function and control method thereof. The power converter includes: a transformer, a power switch, a switch control unit, a signal coupling circuit, a synchronous rectifying switch and a secondary side control circuit. The switch control unit generates an operation signal according to a feedback signal, and generates a first synchronous signal which is related to the operation signal. The signal coupling circuit couples the first synchronous signal to generate a second synchronous signal. The synchronous rectifying switch is turned ON/OFF according to a synchronous rectifying switch signal, for synchronous rectification. The secondary side control circuit generates the synchronous rectifying switch signal according to a secondary side level detection signal and the second synchronous signal, to control the synchronous rectifying switch. The ON time of the power switch and the ON time of the synchronous rectifying switch do not overlap.

公开(公告)号：US20180138818A1

公开(公告)日：2018-05-17

申请号：US15809595

申请日：2017-11-10

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Ta-Yung Yang ,  Tzu-Chen Lin ,  Bing Zeng ,  Li-Di Luo

IPC: H02M3/335

CPC classification number: H02M3/33523 ,  H02M3/33592

Abstract: A flyback power converter includes a transformer, a power switch, a power switch control circuit, a synchronous rectification (SR) switch, an SR switch control circuit, and a signal coupler circuit. The signal coupler circuit includes a primary port and a secondary port, wherein the primary port is electrically connected to the power switch control circuit, and the secondary port is electrically connected to the SR switch control circuit. The primary port and the secondary port receive different signals generated by the power switch control circuit and the SR switch control circuit respectively, and the signal coupler circuit senses and converts the different signals to generate corresponding converted signals at the secondary port and the primary port respectively in different and non-overlapping time periods, without direct contact or direct connection between the primary side and the secondary side of the transformer.

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：US10014786B2

公开(公告)日：2018-07-03

申请号：US15809595

申请日：2017-11-10

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Ta-Yung Yang ,  Tzu-Chen Lin ,  Bing Zeng ,  Li-Di Luo

IPC: H02M3/335

CPC classification number: H02M3/33523 ,  H02M3/33592 ,  Y02B70/1475

Abstract: A flyback power converter includes a transformer, a power switch, a power switch control circuit, a synchronous rectification (SR) switch, an SR switch control circuit, and a signal coupler circuit. The signal coupler circuit includes a primary port and a secondary port, wherein the primary port is electrically connected to the power switch control circuit, and the secondary port is electrically connected to the SR switch control circuit. The primary port and the secondary port receive different signals generated by the power switch control circuit and the SR switch control circuit respectively, and the signal coupler circuit senses and converts the different signals to generate corresponding converted signals at the secondary port and the primary port respectively in different and non-overlapping time periods, without direct contact or direct connection between the primary side and the secondary side of the transformer.

公开(公告)号：US20160344296A1

公开(公告)日：2016-11-24

申请号：US15144610

申请日：2016-05-02

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Li-Di Luo ,  Yu-Kai Chen ,  Yu-Chang Chen

IPC: H02M3/335 ,  H02M1/08

CPC classification number: H02M3/33523 ,  H02M1/08 ,  H02M3/33592 ,  Y02B70/1475

Abstract: The present invention discloses a power converter with synchronous control function and control method thereof. The power converter includes: a transformer, a power switch, a switch control unit, a signal coupling circuit, a synchronous rectifying switch and a secondary side control circuit. The switch control unit generates an operation signal according to a feedback signal, and generates a first synchronous signal which is related to the operation signal. The signal coupling circuit couples the first synchronous signal to generate a second synchronous signal. The synchronous rectifying switch is turned ON/OFF according to a synchronous rectifying switch signal, for synchronous rectification. The secondary side control circuit generates the synchronous rectifying switch signal according to a secondary side level detection signal and the second synchronous signal, to control the synchronous rectifying switch. The ON time of the power switch and the ON time of the synchronous rectifying switch do not overlap.

Abstract translation: 本发明公开了一种具有同步控制功能的电力转换器及其控制方法。 电力转换器包括：变压器，电源开关，开关控制单元，信号耦合电路，同步整流开关和次级侧控制电路。 开关控制单元根据反馈信号产生操作信号，并产生与操作信号相关的第一同步信号。 信号耦合电路耦合第一同步信号以产生第二同步信号。 同步整流开关根据同步整流开关信号导通/关断，用于同步整流。 次级侧控制电路根据次级侧电平检测信号和第二同步信号生成同步整流开关信号，以控制同步整流开关。 电源开关的接通时间和同步整流开关的接通时间不重叠。

公开(公告)号：US20190149032A1

公开(公告)日：2019-05-16

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: H02M1/08 ,  H02M3/335

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：US09755529B2

公开(公告)日：2017-09-05

申请号：US15147182

申请日：2016-05-05

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Yu-Chang Chen ,  Li-Di Luo ,  Tzu-Chen Lin

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

CPC classification number: H02M3/33515 ,  H02M1/08 ,  H02M3/33592 ,  H02M2001/0006 ,  H02M2001/0009 ,  Y02B70/1475

Abstract: The present invention provides a flyback power converter and a control circuit thereof. The flyback power converter includes a transformer, a power switch, a driver, a synchronous rectification (SR) switch, a controller, and a signal coupler circuit. The transformer has a primary winding and a secondary winding. The power switch controls the conduction time of the primary winding; and the SR switch controls the conduction time of the secondary winding. The controller controls the SR switch and generates an ON pulse signal and an OFF pulse signal in a normal operation mode. When an output voltage reaches a lower limit voltage, the flyback power converter operates in the normal operation mode. The driver generates a switching signal according to the ON pulse signal and the OFF pulse signal in the normal operation mode, to determine a start conduction time point and an end conduction time point of the primary winding.

公开(公告)号：US20160329819A1

公开(公告)日：2016-11-10

申请号：US15147182

申请日：2016-05-05

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Yu-Chang Chen ,  Li-Di Luo ,  Tzu-Chen Lin

IPC: H02M3/335 ,  H02M1/08

CPC classification number: H02M3/33515 ,  H02M1/08 ,  H02M3/33592 ,  H02M2001/0006 ,  H02M2001/0009 ,  Y02B70/1475

Abstract: The present invention provides a flyback power converter and a control circuit thereof. The flyback power converter includes a transformer, a power switch, a driver, a synchronous rectification (SR) switch, a controller, and a signal coupler circuit. The transformer has a primary winding and a secondary winding. The power switch controls the conduction time of the primary winding; and the SR switch controls the conduction time of the secondary winding. The controller controls the SR switch and generates an ON pulse signal and an OFF pulse signal in a normal operation mode. When an output voltage reaches a lower limit voltage, the flyback power converter operates in the normal operation mode. The driver generates a switching signal according to the ON pulse signal and the OFF pulse signal in the normal operation mode, to determine a start conduction time point and an end conduction time point of the primary winding.

Abstract translation: 本发明提供一种反激式功率转换器及其控制电路。 反激式功率转换器包括变压器，电源开关，驱动器，同步整流（SR）开关，控制器和信号耦合器电路。 变压器具有初级绕组和次级绕组。 电源开关控制初级绕组的导通时间; 并且SR开关控制次级绕组的导通时间。 控制器控制SR开关，并在正常工作模式下产生ON脉冲信号和OFF脉冲信号。 当输出电压达到下限电压时，反激式电源转换器在正常工作模式下工作。 驱动器根据ON脉冲信号和OFF脉冲信号在正常工作模式下产生开关信号，以确定初级绕组的启动导通时间点和结束导通时间点。