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28 条记录 (耗时 0.014 秒)

    Circuit for sensing motor load current
    14.
    发明授权
    Circuit for sensing motor load current 失效
    感应电机负载电流的电路

    公开(公告)号：US5900714A

    公开(公告)日：1999-05-04

    申请号：US963936

    申请日：1997-11-04

    申请人： Ajit Dubhashi ,  Stefano Clemente ,  Christopher C. Chey

    发明人： Ajit Dubhashi ,  Stefano Clemente ,  Christopher C. Chey

    IPC分类号： H02P6/18 ,  G01R19/00 ,  H02P6/00 ,  H02P5/28

    CPC分类号： G01R19/0092 ,  H02P6/28

    摘要： A current sensing circuit including a shunt resistor coupled, at one end, to the low-side transistor of a half bridge circuit and, at its other end, to a load. The voltage sensed across the shunt resistor is proportional to the current delivered to the load. A level shifting circuit is provided to transpose the sensed voltage to a low voltage signal which can be fed back to control commutation of the transistors in the half bridge circuit.

    摘要翻译： 一种电流感测电路，包括分流电阻器，其一端耦合到半桥电路的低侧晶体管，并且在另一端耦合到负载。 分流电阻两端感应的电压与传送到负载的电流成比例。 提供电平移位电路以将感测到的电压转换为可被反馈以控制半桥电路中的晶体管的换向的低电压信号。

    Gate control circuit for prevention of turn-off avalanche of power MOSFETs
    15.
    发明授权
    Gate control circuit for prevention of turn-off avalanche of power MOSFETs 有权
    用于防止功率MOSFET关断雪崩的门控电路

    公开(公告)号：US07236340B2

    公开(公告)日：2007-06-26

    申请号：US10364956

    申请日：2003-02-11

    申请人： Shahin Maloyan ,  Ajit Dubhashi

    发明人： Shahin Maloyan ,  Ajit Dubhashi

    IPC分类号： H02H9/08

    CPC分类号： H03K17/166 ,  H03K4/00

    摘要： A switch in an inductive circuit is prevented from avalanche operation when the switch is turned off. By preventing avalanche, the associated EMI is reduced or eliminated. Switch avalanche can be prevented using an active component, such as a transistor, or a passive component, such as a resistor, coupled to the switch gate to control current in the switch gate. By controlling current in the switch gate during turn-off, avalanche operation can be prevented without a significant increase in turn-off energy.

    摘要翻译： 当开关断开时，防止电感电路中的开关发生雪崩操作。 通过防止雪崩，减少或消除了相关的EMI。 可以使用耦合到开关栅极的有源部件（例如晶体管或诸如电阻器）的无源部件来防止开关雪崩以控制开关栅极中的电流。 通过在关断期间控制开关栅极中的电流，可以防止雪崩操作，而不会明显增加关断能量。

    Current limited buck power supply
    16.
    发明授权
    Current limited buck power supply 有权

    公开(公告)号：US06650098B2

    公开(公告)日：2003-11-18

    申请号：US09935578

    申请日：2001-08-24

    申请人： Ajit Dubhashi ,  Vijay Bolloju ,  Bertrand Vaysse

    发明人： Ajit Dubhashi ,  Vijay Bolloju ,  Bertrand Vaysse

    IPC分类号： G05F156

    CPC分类号： H02M3/156 ,  H02M2001/0048 ,  Y02B70/1491

    摘要： A novel power supply control circuit topology uses a standard power supply controller to control a high side switch in an electronic circuit. A feedback voltage referenced to ground (or negative bus level) is level-shifted to a high side controller by means of a diode/capacitor/resistor network. Power to the high side controller is supplied by using the feedback output voltage. The circuit can be used instead of conventional flyback converters, particularly in low voltage applications. The circuit requires fewer pins on the transformer/inductor, leading to lower cost and size, particularly as compared to prior art flyback converters. Lower voltage rating required for the switch reduces noise and losses in the device.

    Method of reducing conducted EMI in motor drive applications
    17.
    发明授权
    Method of reducing conducted EMI in motor drive applications 有权
    降低电动机驱动应用中传导EMI的方法

    公开(公告)号：US06583682B1

    公开(公告)日：2003-06-24

    申请号：US09553757

    申请日：2000-04-21

    申请人： Ajit Dubhashi ,  Bertrand Vaysse

    发明人： Ajit Dubhashi ,  Bertrand Vaysse

    IPC分类号： H03H701

    CPC分类号： H02M1/44 ,  H02M1/12 ,  H02M5/45 ,  H02M7/003 ,  H02M2001/123

    摘要： Conductive EMI in motor drive circuits is reduced by interposing inductors in the ground line. The common mode current enters the motor drive circuit through the two supply leads and leaves the system through the ground lead. The ground current typically is very high frequency but very low in rms amperage. Interposing an induction (low current, very high L) in the ground line advantageously reduces EMI. The inventive method reduces.or eliminates the need for filtering capacitors across the rectifier of the motor drive circuit. In addition, the inventive method minimizes the common mode choke to merely a wraparound ferrite core over the input wires. EMI emissions are reduced further by sandwiching ground traces along with power traces and connecting to.the heat sink with the shortest possible route. This reduces the ground loop area, which consequently reduces emissions.

    摘要翻译： 电感驱动电路中的导电EMI通过在地线中插入电感来减少。 共模电流通过两个电源线进入电机驱动电路，并将系统通过接地引线。 接地电流通常是非常高的频率，但是均方根电流是非常低的。 在地线中插入感应（低电流，非常高的L）有利地降低了EMI。 本发明的方法减少了，或者消除了对电动机驱动电路的整流器进行滤波电容的需要。 此外，本发明的方法将共模扼流圈最小化为仅在输入线上的环绕铁氧体磁心。 通过将接地迹线与功率迹线夹在一起并以尽可能短的路线连接到散热器，进一步降低了EMI辐射。 这减少了接地回路面积​​，从而减少了排放。

    Circuit for synchronous rectification with minimal reverse recovery losses
    18.
    发明授权
    Circuit for synchronous rectification with minimal reverse recovery losses 有权
    具有最小反向恢复损耗的同步整流电路

    公开(公告)号：US06396333B2

    公开(公告)日：2002-05-28

    申请号：US09753599

    申请日：2001-01-04

    申请人： Ajit Dubhashi ,  Brian Pelly

    发明人： Ajit Dubhashi ,  Brian Pelly

    IPC分类号： G05F302

    CPC分类号： G05F1/613

    摘要： A circuit for synchronous rectification including two power MOSFET transistor switches in which the bottom switch is a P channel MOSFET, rather than an N channel MOSFET. The circuit of the present invention uses a single channel driver, rather than a dual driver and eliminates the deadtime associated with conventional circuits, thus minimizing reverse recovery losses. In an alternative arrangement, the position of the output filter is switched so that the N channel MOSFET conducts during the freewheeling time and the P channel MOSFET (with a larger RDSON) conducts during the conductor charge cycle.

    摘要翻译： 一个用于同步整流的电路，包括两个功率MOSFET晶体管开关，其中底部开关是P沟道MOSFET，而不是N沟道MOSFET。 本发明的电路使用单通道驱动器而不是双驱动器，并且消除与常规电路相关联的死区时间，从而最小化反向恢复损耗。 在替代布置中，输出滤波器的位置被切换，使得N沟道MOSFET在续流时间期间导通，并且在导体充电周期期间P沟道MOSFET（具有较大的RDSON）导通。