公开(公告)号：US20210226541A1

公开(公告)日：2021-07-22

申请号：US16790767

申请日：2020-02-14

Applicant: Power Forest Technology Corporation

Inventor： Wen-Sheng Wang ,  Chia-Hsien Liu

IPC: H02M3/335 ,  H02M1/00

Abstract: A voltage conversion apparatus and a voltage conversion method thereof are provided. A conversion circuit converts outputs of a plurality of secondary windings to generate a conversion voltage or a conversion current to a resistor network of a feedback circuit to thereby change impedance characteristics of the resistor network. The feedback circuit adjusts a feedback voltage in response to the change in the impedance characteristics of the resistor network, so that a control circuit controls an output of a transformer circuit according to the feedback voltage.

公开(公告)号：US11205967B2

公开(公告)日：2021-12-21

申请号：US16790767

申请日：2020-02-14

Applicant: Power Forest Technology Corporation

Inventor： Wen-Sheng Wang ,  Chia-Hsien Liu

IPC: H02M3/335 ,  H02M1/00

Abstract: A voltage conversion apparatus and a voltage conversion method thereof are provided. A conversion circuit converts outputs of a plurality of secondary windings to generate a conversion voltage or a conversion current to a resistor network of a feedback circuit to thereby change impedance characteristics of the resistor network. The feedback circuit adjusts a feedback voltage in response to the change in the impedance characteristics of the resistor network, so that a control circuit controls an output of a transformer circuit according to the feedback voltage.

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。