公开(公告)号：US09906138B2

公开(公告)日：2018-02-27

申请号：US14623501

申请日：2015-02-17

Applicant: Power Forest Technology Corporation

Inventor： Po-Jen Ke

IPC: H02M3/335 ,  H02M1/32

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.

公开(公告)号：US09729043B2

公开(公告)日：2017-08-08

申请号：US14548290

申请日：2014-11-20

Applicant: Power Forest Technology Corporation

Inventor： Yun-Chi Chiang

IPC: H02M3/156 ,  H02M1/32 ,  H02M1/36 ,  H02M7/217

CPC classification number: H02M1/32 ,  H02M1/36 ,  H02M3/156 ,  H02M7/217

Abstract: A power conversion apparatus and a protection method of the power conversion apparatus while a feedback current signal of the power conversion apparatus is abnormal are provided. The protection method includes a step of stopping switching a power switch if a duty cycle of a pulse width modulation signal is continuously greater than a preset duty cycle for at least one signal cycle and a voltage of a current sensing signal is smaller than a preset voltage level during the at least one signal cycle.

公开(公告)号：US09661705B1

公开(公告)日：2017-05-23

申请号：US15172160

申请日：2016-06-03

Applicant: Power Forest Technology Corporation

Inventor： Yang-Tai Tseng

IPC: H05B41/28 ,  H05B33/08

CPC classification number: H05B33/0815 ,  H05B33/0845 ,  H05B33/089

Abstract: A power conversion apparatus including a power conversion circuit, a light-emitting unit and a control chip is provided. The control chip has a multi-function pin and a feedback pin, where the multi-function pin and the feedback pin respectively receive a dimming signal and a feedback signal reflecting an output current of the light-emitting unit, and the control chip determines whether to generate a PWM signal to a power switch of the power conversion circuit according to the dimming signal and the feedback signal based on a duty ratio of the dimming signal.

公开(公告)号：US20170012539A1

公开(公告)日：2017-01-12

申请号：US14884784

申请日：2015-10-16

Applicant: Power Forest Technology Corporation

Inventor： Chun-Teh Chen

IPC: H02M3/335

CPC classification number: H02M3/33523 ,  H02M2001/0009

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 converts an input voltage into a direct current (DC) output voltage. The control chip generates a pulse width modulation (PWM) signal for controlling operations of the flyback power conversion circuit. The detection auxiliary circuit assists the control chip in obtaining a first detection voltage via a multi-function detection pin of the control chip within an enabling period of the PWM signal, so as to execute an over current detection according to the first detection voltage. Besides, the detection auxiliary circuit assists the control chip in obtaining a second detection voltage via the multi-function detection pin within a disabling period of the PWM signal, so as to execute a valley voltage detection according to the second detection voltage.

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将输入电压转换为直流（DC）输出电压。 控制芯片产生用于控制回扫功率转换电路的操作的脉宽调制（PWM）信号。 检测辅助电路通过控制芯片的多功能检测引脚在PWM信号的使能周期内帮助控制芯片获得第一检测电压，从而根据第一检测电压执行过电流检测。 此外，检测辅助电路辅助控制芯片在PWM信号的禁用周期内通过多功能检测引脚获得第二检测电压，以便根据第二检测电压执行谷值电压检测。

公开(公告)号：US09510408B1

公开(公告)日：2016-11-29

申请号：US14956394

申请日：2015-12-02

Applicant: Power Forest Technology Corporation

Inventor： Yang-Tai Tseng

IPC: H05B33/08

CPC classification number: H05B33/0815 ,  H05B33/0848

Abstract: A LED backlight module including a LED string and a driving apparatus is provided. The driving apparatus comprises a sensing resistor, an adjustable voltage-divider circuit, a comparator, a power converter and a control circuit. The sensing resistor is coupled between a cathode of the LED string and a ground potential and generates a feedback voltage. The adjustable voltage-divider circuit generates a reference voltage according to a dividing ratio which is controlled by a first signal set and a second signal set. The comparator compares the feedback voltage and the reference voltage, and generates a control signal accordingly. The power converter provides a DC voltage to an anode of the LED string according to the control signal. The control circuit counts a disable period of a dimming signal to generate the first signal set, and counts an enable period of the dimming signal to generate the second signal set.

Abstract translation: 提供了包括LED串和驱动装置的LED背光模组。 驱动装置包括感测电阻器，可调节分压器电路，比较器，功率转换器和控制电路。 感测电阻器耦合在LED串的阴极和接地电位之间并产生反馈电压。 可调节分压器电路根据由第一信号组和第二信号组控制的分频比产生参考电压。 比较器比较反馈电压和参考电压，并相应地产生一个控制信号。 功率转换器根据控制信号向LED串的阳极提供直流电压。 控制电路对调光信号的禁止周期进行计数以产生第一信号组，并对调光信号的使能周期进行计数，以产生第二信号组。

公开(公告)号：US20160099648A1

公开(公告)日：2016-04-07

申请号：US14571003

申请日：2014-12-15

Applicant: Power Forest Technology Corporation

Inventor： Kwan-Jen Chu

IPC: 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。