公开(公告)号：US20160190947A1

公开(公告)日：2016-06-30

申请号：US14689041

申请日：2015-04-16

Applicant: Power Forest Technology Corporation

Inventor： Chein-Kuo Shein

IPC: H02M3/335 ,  H02M1/08

CPC classification number: H02M3/33592 ,  H02M2001/0032 ,  H02M2001/0054 ,  Y02B70/1475 ,  Y02B70/1491 ,  Y02B70/16

Abstract: A power conversion apparatus is provided. The power conversion apparatus includes a transformer, a synchronous rectification (SR) transistor and an SR control circuit. A first terminal of a primary side of the transformer receives an input voltage. A first terminal of a secondary side of the transformer provides an output voltage to a load. A first drain/source terminal of the SR transistor is coupled to a second terminal of the secondary side of the transformer. A second drain/source terminal of the SR transistor is coupled to a first ground terminal. A gate terminal of the SR transistor receives a control signal. The SR control circuit receives a signal of the first drain/source terminal of the SR transistor to determine statuses of the load and generate the control signal. When the load is a light load, the SR control circuit enters a power-saving mode and turns off the SR transistor.

Abstract translation: 提供电力转换装置。 电力转换装置包括变压器，同步整流（SR）晶体管和SR控制电路。 变压器初级侧的第一端接收输入电压。 变压器的次级侧的第一端子向负载提供输出电压。 SR晶体管的第一漏极/源极端子耦合到变压器的次级侧的第二端子。 SR晶体管的第二漏极/源极端子耦合到第一接地端子。 SR晶体管的栅极端子接收控制信号。 SR控制电路接收SR晶体管的第一漏极/源极端子的信号，以确定负载的状态并产生控制信号。 当负载轻负载时，SR控制电路进入省电模式并关断SR晶体管。

公开(公告)号：US20160190936A1

公开(公告)日：2016-06-30

申请号：US14623501

申请日：2015-02-17

Applicant: Power Forest Technology Corporation

Inventor： Po-Jen Ke

IPC: H02M3/335

CPC classification number: H02M3/33507 ,  H02M1/32

Abstract: A power conversion apparatus including a flyback power conversion circuit, a control chip and a detection auxiliary circuit is provided. The flyback power conversion circuit receives and converts an input voltage into a DC output voltage. The control chip generates a PWM signal in response to a power supplying requirement to control the operation of the flyback power conversion circuit, wherein the control chip has a single multi-function detection pin. The detection auxiliary circuit assists the control chip to obtain a first detection voltage via the multi-function detection pin, such that the control chip performs a detection of an over temperature protection (OTP) and a detection of an over voltage protection (OVP) synchronously according to the first detection voltage. The first detection voltage is related to the DC output voltage or a thermal voltage of an environment temperature.

Abstract translation: 提供一种包括反激式电力转换电路，控制芯片和检测辅助电路的电力转换装置。 反激式功率转换电路接收并将输入电压转换为直流输出电压。 控制芯片响应于供电要求而产生PWM信号，以控制反激式功率转换电路的操作，其中控制芯片具有单个多功能检测引脚。 检测辅助电路通过多功能检测引脚帮助控制芯片获得第一检测电压，使得控制芯片同时执行过温保护（OTP）检测和过电压保护（OVP）检测 根据第一检测电压。 第一检测电压与直流输出电压或环境温度的热电压有关。

公开(公告)号：US09350251B2

公开(公告)日：2016-05-24

申请号：US14493357

申请日：2014-09-23

Applicant: Power Forest Technology Corporation

Inventor： Kwan-Jen Chu

IPC: H02M3/335 ,  H02M1/32 ,  H02M1/00

CPC classification number: H02M3/33507 ,  H02M1/32 ,  H02M2001/0009

Abstract: A power conversion apparatus and an over power protection method thereof are provided. A number of times a sensing voltage exceeding a reference voltage is counted, so as to determine whether to disable a power switch in the power conversion apparatus according to the number of times the sensing voltage exceeding the reference voltage, in which the sensing voltage corresponds to a current flowing through the power switch on a resistor.

Abstract translation: 提供了电力转换装置及其过功率保护方法。 对感测电压超过参考电压的次数进行计数，以便根据感测电压超过参考电压的次数确定是否禁用电力转换装置中的电力开关，其中感测电压对应于 一个电流流过电阻上的电源开关。

公开(公告)号：US09343977B2

公开(公告)日：2016-05-17

申请号：US14571003

申请日：2014-12-15

Applicant: Power Forest Technology Corporation

Inventor： Kwan-Jen Chu

IPC: H02M1/32 ,  H02M3/335

CPC classification number: H02M3/33507 ,  H02M1/32

Abstract: A power conversion apparatus and an over power protection method thereof are provided. A number of times a detection voltage being greater than a first reference voltage and a number of times the detection voltage being greater than a second reference voltage are counted, so as to obtain a first count value and a second count value, in which the detection voltage is a voltage on a resistor in response to a current flowing through a power switch. Stop switching the power switch when the first count value is greater than or equal to a first threshold value or when the second count value is greater than or equal to a second threshold value.

Abstract translation: 提供了电力转换装置及其过功率保护方法。 对大于第一参考电压的检测电压和检测电压大于第二参考电压的次数进行多次计数，以获得第一计数值和第二计数值，其中检测 电压是电流响应于电流流过电源开关的电压。 当第一计数值大于或等于第一阈值时或当第二计数值大于或等于第二阈值时，停止切换电源开关。

公开(公告)号：US20160043645A1

公开(公告)日：2016-02-11

申请号：US14493357

申请日：2014-09-23

Applicant: Power Forest Technology Corporation

Inventor： Kwan-Jen Chu

IPC: H02M3/335

CPC classification number: H02M3/33507 ,  H02M1/32 ,  H02M2001/0009

Abstract: A power conversion apparatus and an over power protection method thereof are provided. A number of times a sensing voltage exceeding a reference voltage is counted, so as to determine whether to disable a power switch in the power conversion apparatus according to the number of times the sensing voltage exceeding the reference voltage, in which the sensing voltage corresponds to a current flowing through the power switch on a resistor.

Abstract translation: 提供了电力转换装置及其过功率保护方法。 对感测电压超过参考电压的次数进行计数，以便根据感测电压超过参考电压的次数确定是否禁用电力转换装置中的电力开关，其中感测电压对应于 一个电流流过电阻上的电源开关。

公开(公告)号：US09060403B2

公开(公告)日：2015-06-16

申请号：US13956383

申请日：2013-08-01

Applicant: Power Forest Technology Corporation

Inventor： Yang-Tai Tseng

IPC: G05F1/00 ,  H05B37/02 ,  H05B39/04 ,  H05B41/36 ,  H05B33/08 ,  G09G3/34

CPC classification number: H05B33/0845 ,  G09G3/3426 ,  H05B33/086

Abstract: A light emitting diode (LED) driving apparatus and an LED backlight system using the same are provided. The backlight control circuit suitable for driving an LED string includes a complex function pin, a driving circuit and a backlight control circuit. The backlight control circuit includes a control current generating unit, a first current comparing unit and a second current comparing unit. The control current generating unit receives a dimming control signal and an enable control signal from the complex function pin to generate a control current accordingly. The first and the second current comparing units are respectively configured to compare the control current with first and second predetermined currents to respectively generate a first and a second control signals. The driving circuit determines to be turned on or off according to the second control signal, and further adjusts a luminance of the LED string according to the first control signal.

Abstract translation: 提供了一种发光二极管（LED）驱动装置和使用其的LED背光系统。 适用于驱动LED串的背光控制电路包括复功能引脚，驱动电路和背光控制电路。 背光控制电路包括控制电流产生单元，第一电流比较单元和第二电流比较单元。 控制电流产生单元接收来自复功能引脚的调光控制信号和使能控制信号，从而相应地产生控制电流。 第一和第二电流比较单元分别配置为将控制电流与第一和第二预定电流进行比较，以分别产生第一和第二控制信号。 驱动电路根据第二控制信号确定为接通或关断，并且还根据第一控制信号调节LED串的亮度。

公开(公告)号：US20140306613A1

公开(公告)日：2014-10-16

申请号：US13958625

申请日：2013-08-05

Applicant: Power Forest Technology Corporation

Inventor： Fu-Yuan Shih ,  Wen-Sheng Wang

IPC: H05B33/08

CPC classification number: H05B33/0815 ,  H05B33/0827

Abstract: A light-emitting-diode (LED) driving apparatus including an AC-DC power conversion stage, a balance circuit and a pulse-width-modulation (PWM) control unit is provided. In the present invention, the LED driving apparatus balances currents flowing through all LED strings by using the balance circuit such that a purpose of current matching is achieved accordingly. In addition, the LED driving apparatus may control the PWM control unit according to an equation between an independent DC output voltage generated by the AC-DC power conversion stage and a control voltage provided by the balance circuit without adopting any boost converter so as to indirectly change a DC output voltage used for directly driving all LED strings and generated by the AC-DC power conversion stage. In this way, the purpose of low cost and high efficiency can be achieved accordingly.

Abstract translation: 提供了包括AC-DC电力转换级，平衡电路和脉冲宽度调制（PWM）控制单元的发光二极管（LED）驱动装置。 在本发明中，LED驱动装置通过使用平衡电路平衡流过所有LED串的电流，从而相应地实现电流匹配的目的。 此外，LED驱动装置可以根据由AC-DC电力转换级产生的独立DC输出电压与由平衡电路提供的控制电压之间的等式来控制PWM控制单元，而不采用任何升压转换器，以间接地 改变用于直接驱动所有LED串并由AC-DC电力转换级产生的直流输出电压。 这样就可以实现低成本，高效率的目的。

公开(公告)号：US20140268935A1

公开(公告)日：2014-09-18

申请号：US13941540

申请日：2013-07-14

Applicant: Power Forest Technology Corporation

Inventor： Yun-Chi Chiang

IPC: H02M1/36

CPC classification number: H02M1/36 ,  H02M7/217

Abstract: An AC/DC converting circuit and a starting method thereof are provided. An AC detection or a rectified AC voltage detection is disabled when the AC voltage or the rectified AC voltage not up to a start-up voltage is detected, so as to shorten a recovery time of a voltage of a power supply terminal of an AC/DC power conversion controller, and further shorten a starting time of the AC/DC converting circuit.

Abstract translation: 提供一种AC / DC转换电路及其启动方法。 当检测到交流电压或整流的交流电压不达到启动电压时，禁止交流检测或整流的交流电压检测，以缩短交流/交流电压的电源端的电压的恢复时间， DC电源转换控制器，进一步缩短AC / DC转换电路的启动时间。

公开(公告)号：US20230058506A1

公开(公告)日：2023-02-23

申请号：US17488335

申请日：2021-09-29

Applicant: Power Forest Technology Corporation

Inventor： Chia-Hsien Liu

IPC: H02M3/335 ,  H02M1/08

Abstract: A power conversion apparatus and a synchronous rectification controller thereof are provided. At least one of a differentiation operation and an integration operation is performed on a drain voltage signal of a synchronous rectification transistor. According to at least one of a differential signal obtained by performing the differential operation and an integral signal obtained by performing the integral operation, it is determined whether to turn on the synchronous rectification transistor at the next time when the drain voltage signal is less than or equal to a turn-on threshold voltage.

公开(公告)号：US20220352827A1

公开(公告)日：2022-11-03

申请号：US17406049

申请日：2021-08-18

Applicant: Power Forest Technology Corporation

Inventor： Chia-Hsien Liu

IPC: H02M3/335

Abstract: A power conversion apparatus and a synchronous rectification (SR) controller thereof are provided. An open-loop control circuit outputs a clamp voltage as a driving voltage when a drain voltage of a synchronous rectification transistor rises to a second voltage, so as to quickly pull down the driving voltage and maintain the driving voltage at a clamp voltage. Therefore, a second control circuit may quickly turn off the synchronous rectification transistor when the drain voltage is greater than a third voltage.