Starter circuit for a fluorescent tube lamp
    2.
    发明公开
    Starter circuit for a fluorescent tube lamp 失效
    荧光灯管起动电路

    公开(公告)号:EP0118309A3

    公开(公告)日:1984-11-14

    申请号:EP84301451

    申请日:1984-03-05

    IPC分类号: H05B41/04

    CPC分类号: H05B41/046

    摘要: A starter circuit for a fluorescent tube lamp is connected between the cathode heaters of the tube to provide an intial heating current and then changes to a high impedance to ignite the tube. The circuit is fed by raw rectified a.c. and has a main thyristor requiring a high holding current to maintain the initial conduction. The current through the main thyristor sets up a voltage across a series diode which triggers a second thyristor to reduce the gate voltage of the main thyristor. The main thyristor ceases conduction when the current falls below the holding value and the inductive ballast impedance then produces a high energy striking pulse for the tube. The pulse voltage is limited to increase its duration. One embodiment generates a single pulse only each time the circuit is switched on and another embodiment produces pulses for a period of time before becoming quiescent. The main thyristor and the voltage limiting means are embodied in a monolithic semiconductor structure.

    Semi conductor device and starter circuit for a fluorescent tube lamp, provided with such a semi conductor device
    3.
    发明公开
    Semi conductor device and starter circuit for a fluorescent tube lamp, provided with such a semi conductor device 失效
    半导体器件及其荧光灯,在这样的半导体装置的起动电路。

    公开(公告)号:EP0118309A2

    公开(公告)日:1984-09-12

    申请号:EP84301451.5

    申请日:1984-03-05

    IPC分类号: H05B41/04 H01L29/743

    CPC分类号: H05B41/046

    摘要: A starter circuit for a fluorescent tube lamp is connected between the cathode heaters of the tube to provide an intial heating current and then changes to a high impedance to ignite the tube. The circuit is fed by raw rectified a.c. and has a main thyristor requiring a high holding current to maintain the initial conduction. The current through the main thyristor sets up a voltage across a series diode which triggers a second thyristor to reduce the gate voltage of the main thyristor. The main thyristor ceases conduction when the current falls below the holding value and the inductive ballast impedance then produces a high energy striking pulse for the tube. The pulse voltage is limited to increase its duration. One embodiment generates a single pulse only each time the circuit is switched on and another embodiment produces pulses for a period of time before becoming quiescent. The main thyristor and the voltage limiting means are embodied in a monolithic semiconductor structure.

    A semiconductor switch device suitable for a.c. power control
    5.
    发明公开
    A semiconductor switch device suitable for a.c. power control 失效
    半导体控制交流电源切换装置。

    公开(公告)号:EP0025291A1

    公开(公告)日:1981-03-18

    申请号:EP80302843.0

    申请日:1980-08-18

    发明人: Lear, Anthony

    摘要: A semiconductor switch device suitable for a.c. power control includesthree4-layer switch components in parallel in a single body of semiconductor material. First and second components are of the same polarity and of opposite polarity to the third component. One end connection of the second component is taken out as a secondary gate connection separate from the corresponding connections of the first and third components. In a preferred mode of use, the secondary gate connection is maintained at a d.c. potential relative to the corresponding connections of the first and third components so as to enable the second component to be conducting during the zero crossings of the a.c. supply and able to maintain the internal voltages required for conduction of either or both of the other components. Circuits are given for integrated circuits embodying the device to permit zero voltage switching power controllers to be made with few external components, and for a proportional controller providing a variable mark-to-space ratio in dependence upon a variable resistor.