公开(公告)号：US06344986B1

公开(公告)日：2002-02-05

申请号：US09595425

申请日：2000-06-15

申请人： Praveen K. Jain ,  Yan-Fei Liu

发明人： Praveen K. Jain ,  Yan-Fei Liu

IPC分类号： H02M542

CPC分类号： H02M1/4225 ,  H02M3/335 ,  Y02B70/126

摘要： In a power factor corrected AC-to-DC power supply system, a DC-to-DC power converter is coupled to the output of an AC-to-DC power converter in order to produce a regulated DC output signal from a rectified AC input signal. The AC-to-DC power converter and the DC-to-DC power converter each includes a switch for controlling the operation of their respective power converter. The AC-to-DC converter includes an inductor. The system provides power factor correction for minimizing harmonic distortion by including a controller that receives the regulated DC output voltage as a feedback signal, and in response, produces a series of drive pulses having predetermined constant duty cycle. These pulses are simultaneously fed to each switch, to operate the respective converters alternately between ON and OFF states. When the AC-to-DC converter is driven by a fixed duty cycle of the series of pulses, power factor correction is improved since the current flowing through the inductor is substantially proportional to the waveform of the rectified AC input signal. By preselecting the value of the inductor, the AC-to-DC converter is operable in a discontinuous mode when the instantaneous rectified AC input signal is low and in a continuous mode when the instantaneous rectified AC input signal is high.

摘要翻译： 在功率因数校正的AC至DC电源系统中，DC-DC电力转换器耦合到AC-DC电力转换器的输出端，以便从整流的AC输入端产生稳定的DC输出信号 信号。 AC-DC电力转换器和DC-DC电力转换器各自包括用于控制其各自功率转换器的操作的开关。 AC-DC转换器包括电感器。 该系统通过包括接收调节的DC输出电压作为反馈信号的控制器来提供用于最小化谐波失真的功率因数校正，并且作为响应，产生具有预定的恒定占空比的一系列驱动脉冲。 这些脉冲同时馈送到每个开关，以在各自的开关状态之间交替地操作相应的转换器。 当由一系列脉冲的固定占空比驱动AC到DC转换器时，功率因数校正被改善，因为流过电感器的电流基本上与整流的AC输入信号的波形成正比。 通过预选电感器的值，当瞬时整流的AC输入信号为低电平时，AC瞬间整流的AC输入信号为高电平时，AC-DC转换器可在不连续模式下工作。

公开(公告)号：US6005782A

公开(公告)日：1999-12-21

申请号：US173034

申请日：1998-10-16

申请人： Praveen K. Jain ,  Yan-Fei Liu ,  Youhao Xi

发明人： Praveen K. Jain ,  Yan-Fei Liu ,  Youhao Xi

IPC分类号： H02M1/34 ,  H02M3/335 ,  H02M1/12 ,  G05F1/10 ,  H02M3/24

CPC分类号： H02M1/34 ,  H02M3/33569 ,  H02M2001/342 ,  Y02B70/1433 ,  Y02B70/1491

摘要： A flyback converter has a main switch coupling a primary winding of a transformer between supply terminals, a duty cycle of the main switch controlling an output of the converter derived from a secondary winding of the transformer. Soft (zero voltage) switching of the main switch is facilitated by a snubber capacitor in parallel with the main switch. An auxiliary circuit coupled in parallel with the snubber capacitor and main switch includes a series-connected auxiliary switch, capacitor, and inductor coupled via another inductor to a full wave rectifier arrangement for recovering energy from the snubber capacitor. Resonant circuits provided by the auxiliary circuit facilitate soft switching of the auxiliary switch for low power loss and high frequency operation. The switches can be MOSFETs with reverse-poled diodes in parallel with their drain-source paths.

摘要翻译： 反激式转换器具有主开关，其在电源端子之间耦合变压器的初级绕组，主开关的占空比控制从变压器的次级绕组获得的转换器的输出。 主开关的软（零电压）开关由与主开关并联的缓冲电容器促成。 与缓冲电容器和主开关并联耦合的辅助电路包括通过另一电感器耦合到全波整流器装置的串联辅助开关，电容器和电感器，用于从缓冲电容器恢复能量。 由辅助电路提供的谐振电路便于辅助开关的软开关，用于低功耗和高频工作。 这些开关可以是反向极化二极管与其漏源路径并联的MOSFET。

公开(公告)号：US20220109048A1

公开(公告)日：2022-04-07

申请号：US17487117

申请日：2021-09-28

申请人： Zhanming Li ,  Yan-Fei Liu ,  Wai Tung Ng

发明人： Zhanming Li ,  Yan-Fei Liu ,  Wai Tung Ng

IPC分类号： H01L29/06 ,  H01L29/20 ,  H01L29/778 ,  H01L29/66

摘要： A gallium nitride (GaN) semiconductor device has first and second electrodes connected to a top metal layer disposed in complementary first and second irregular shapes, each irregular shape including a wide connection area at a first end, a tapered area, and a narrow area at a second end. The first and second irregular shapes are arranged adjacent each other along complementary edges such that a gap between the complementary edges is of substantially constant width. The first and second wide connection areas include pads for wire bond or land grid array electrical connections to external circuitry. The first and second irregular shapes for source and drain metal of a field effect transistor (FET) or high electron mobility transistor (HEMT) allows the width of the gate finger to be short so that electrical current injected from the gate can reach all portions of the gate fingers efficiently during high frequency switching, making the topology suitable for high voltage power devices.

公开(公告)号：US11107755B2

公开(公告)日：2021-08-31

申请号：US16871026

申请日：2020-05-10

申请人： Zhanming Li ,  Yue Fu ,  Yan-Fei Liu

发明人： Zhanming Li ,  Yue Fu ,  Yan-Fei Liu

IPC分类号： H01L23/495 ,  H01L23/00

摘要： Packaging methods and structures for lateral high voltage gallium nitride (GaN) devices achieve electrical isolation while also maintaining thermal dissipation. The electrical isolation reduces or eliminates vertical leakage current, improving high voltage performance. The packages may use or be compatible standards such as JEDEC, which reduces packaging cost and facilitates implementation of the packaged devices in conventional circuit design approaches.

公开(公告)号：US20190379374A1

公开(公告)日：2019-12-12

申请号：US16423138

申请日：2019-05-27

申请人： Zhanming Li ,  Yan-Fei Liu ,  Yue Fu ,  Wai Tung Ng

发明人： Zhanming Li ,  Yan-Fei Liu ,  Yue Fu ,  Wai Tung Ng

IPC分类号： H03K17/30 ,  H03K17/06 ,  H03K17/22

摘要： A gate driver circuit for a gallium nitride (GaN) power transistor includes a RS-flipflop that receives a first pulse train at an S input terminal and a second pulse train at an R input terminal, and produces an output pulse train, and an amplifier that amplifies the output pulse train and produces a gate driver signal for the GaN power transistor. The RS-flipflop and the amplifier may be implemented together on a GaN monolithic integrated circuit, optionally together with the GaN power transistor. The GaN power transistor may be a high-side switch of a half-bridge circuit. The RS-flipflop may be implemented with enhancement mode and depletion mode GaN high electron mobility transistors (HEMTs). Embodiments avoid drawbacks of prior hybrid (e.g., silicon-GaN) approaches, such as parasitic inductances from bonding wires and on-board metal traces, especially at high operating frequencies, as well as reduce implementation cost and improve performance.

公开(公告)号：US20180309383A1

公开(公告)日：2018-10-25

申请号：US15767721

申请日：2016-11-07

申请人： Yan-Fei LIU

发明人： Hongliang Wang ,  Yan-Fei Liu

IPC分类号： H02M7/483 ,  H02M1/32 ,  H02M7/5387

CPC分类号： H02M7/483 ,  H02M1/32 ,  H02M7/487 ,  H02M7/5387 ,  Y02E10/56

摘要： A five-voltage level inverter topology circuit, and three-phase and five-voltage level inverter topology circuit, suitable for use with two serial-connected direct current (DC) power sources (C1, C2), comprise: a half-bridge inverter circuit comprising a first circuit module (M1) and a second circuit module (M2). The half-bridge inverter circuit can output 5 voltage levels including a 0V level. The five-voltage level inverter topology circuit adopts a 5-voltage level half-bridge structure, and only requires an alternating current (AC) filtering inductor (L1), thereby reducing a system cost and size, removing a leakage current, and providing high efficiency.

公开(公告)号：US07612602B2

公开(公告)日：2009-11-03

申请号：US11045055

申请日：2005-01-31

申请人： Zhihua Yang ,  Yan-Fei Liu

发明人： Zhihua Yang ,  Yan-Fei Liu

IPC分类号： H03K17/74

CPC分类号： H03K17/04163 ,  H02M1/08 ,  H03K17/04123

摘要： A resonate gate drive circuit for driving at least one power switching devices recovers energy loss for charging and discharging the input capacitance of the power switching devices. The gate drive circuit charging and discharging the gate capacitor with a high level current, so the switching loss of the power switching devices can also be reduced. The gate drive circuit can clamp and keep the voltage across the gate capacitor to a certain level while the power switching devices turn on, and it can also clamp and keep the voltage across the gate capacitor to almost zero while the power switching devices turn off. The gate drive circuit comprises four small semiconductor bidirectional conducting switching devices connected in full-bridge configuration. An inductor is connected to the two junctions of the full-bridge configuration to help switching the current direction. A capacitor in series with the inductor is necessary for some applications. A bootstrap circuit, which is widely used in conventional gate drive circuitry, is also necessary for this resonant gate drive circuit when it is adopted for high-side and low-side applications.

摘要翻译： 用于驱动至少一个电力开关装置的谐振栅极驱动电路恢复用于对功率开关装置的输入电容进行充电和放电的能量损失。 栅极驱动电路以高电平电流对栅极电容器进行充电和放电，因此也可以降低功率开关器件的开关损耗。 栅极驱动电路可以在功率开关器件导通的同时将栅极电容器两端的电压钳位并保持一定水平，并且在电源开关器件关闭时，它也可以钳位并保持栅极电容器两端的电压几乎为零。 栅极驱动电路包括以全桥配置连接的四个小型半导体双向导通开关装置。 电感器连接到全桥配置的两个连接点，以帮助切换电流方向。 与电感器串联的电容器对于某些应用是必需的。 当用于高边和低边应用时，该谐振栅极驱动电路也需要用于常规栅极驱动电路的自举电路。

公开(公告)号：US20080122422A1

公开(公告)日：2008-05-29

申请号：US11951228

申请日：2007-12-05

申请人： Wanfeng Zhang ,  Yan-Fei Liu ,  Bin Wu

发明人： Wanfeng Zhang ,  Yan-Fei Liu ,  Bin Wu

IPC分类号： H02M3/156

CPC分类号： H02M3/157 ,  H02M1/4225 ,  H02M2001/4275 ,  Y02B70/126 ,  Y02P80/112

摘要： A method and apparatus to implement parallel current mode control that is suitable for digital and analog implementation. A duty cycle algorithm is composed of a voltage term and a parallel current term which depends on the inductor current change between the inductor current value at the beginning of a switching cycle and the reference inductor current value at the end of that switching cycle. Parallel current mode control can be applied to all DC-DC converters, including both non-isolated and isolated topologies. It can also be applied to AC-DC converters with power factor correction.

摘要翻译： 一种适用于数字和模拟实现的并行电流模式控制的方法和装置。 占空比算法由电压项和并联电流项组成，取决于开关周期开始时的电感电流值与开关周期结束时的参考电感电流值之间的电感电流变化。 并联电流模式控制可应用于所有DC-DC转换器，包括非隔离和隔离拓扑。 它也可以应用于具有功率因数校正的AC-DC转换器。

公开(公告)号：US06980783B2

公开(公告)日：2005-12-27

申请号：US10265168

申请日：2002-10-03

申请人： Yan-Fei Liu ,  Raymond Orr ,  Kai Xu

发明人： Yan-Fei Liu ,  Raymond Orr ,  Kai Xu

IPC分类号： H02M3/156 ,  H04B1/10

CPC分类号： H02M3/156 ,  H02M2001/0009 ,  H02M2001/0022

摘要： A circuit controls the low frequency load currents drawn by components of telecommunications systems. The circuit includes a power converter, a first sense circuit, a second sense circuit, a comparator, and a power converter control circuit. The power converter control circuit controls the power converter's duty cycle in accordance with the input signal compared to a reference. In this manner, the low frequency load currents may be easily and economically controlled.

摘要翻译： 电路控制电信系统组件所绘制的低频负载电流。 该电路包括功率转换器，第一感测电路，第二感测电路，比较器和功率转换器控制电路。 功率转换器控制电路根据与参考相比的输入信号来控制功率转换器的占空比。 以这种方式，可以容易且经济地控制低频负载电流。

公开(公告)号：US20050024894A1

公开(公告)日：2005-02-03

申请号：US10729970

申请日：2003-12-09

申请人： Yan-Fei Liu ,  Sheng Ye

发明人： Yan-Fei Liu ,  Sheng Ye

IPC分类号： H02M3/28 ,  H02M3/335 ,  H02J1/00

CPC分类号： H02M3/285 ,  H02M3/33576

摘要： One DC-DC converter includes primary side circuit between high and low side inputs including first primary winding of first transformer, and auxiliary section; and rectifier circuits, with separate secondary windings of first transformer, and in parallel with one another and output and capacitor; an output capacitor between outputs and across rectifier circuit. Auxiliary causes transfer of power from first primary to first secondary winding and operation without saturation. Another converter includes primary side circuit including primary winding of plurality of transformers, and an auxiliary section; a rectifier circuit having secondary winding of the plurality of transformers, the rectifier circuit in parallel with output and capacitor; an output capacitor between outputs and across rectifier circuit. Auxiliary section includes switches for connecting and disconnecting primary windings from input, and for resetting transformers. Alternatively, auxiliary section includes switches and capacitors. Switches and capacitors in auxiliary section shared between transformers.

摘要翻译： 一个DC-DC转换器包括高低侧输入之间的初级侧电路，包括第一变压器的第一初级绕组和辅助部分; 和整流电路，具有第一变压器的单独的次级绕组，并且彼此并联并输出和电容器; 输出和整流电路之间的输出电容。 辅助电源从第一次初级到次级绕组转换，无饱和操作。 另一转换器包括：初级侧电路，包括多个变压器的初级绕组和辅助部分; 整流电路具有多个变压器的次级绕组，整流电路与输出和电容并联; 输出和整流电路之间的输出电容。 辅助部分包括用于从输入端连接和断开初级绕组以及用于复位变压器的开关。 或者，辅助部分包括开关和电容器。 变压器共用的辅助部分中的开关和电容器。