| 摘要 |
A broadband signal-inverting video amplifier 10 with high speed comprises a generally conventional main cascade amplifier 20, a first and second current-increasing cascade amplifier device 14, 16, which are capacitively CB3, CB2 connected to the main cascade amplifier 20. The first current-increasing amplifier 14 provides a positive current peak 62 in response to an input video signal 22 suddenly decreasing, where the positive current peak 62 provided is taken to the main cascade amplifier 20 in a way which means that the current peak 62 is added to the current I through the main amplifier 20 when the amplified video signal 22 goes in a positive direction. The second current-increasing amplifier 16 provides a negative current peak 64 in response to the input video signal suddenly increasing, where the negative current peak 64 provided is taken to the main cascade amplifier 20 in a way which means that this current peak is subtracted from the current I through the main amplifier 20 when the amplified video signal 22 goes in a negative direction. The positive and negative peaks 62, 64 cause the amplified output video signal 42 to have rising and falling periods which are less than approx. 3.5 nanoseconds for loads C TOTAL of at least 25 pF at output voltages of at least 40 volts from peak to peak and which are at most 1.8 nanoseconds at approx. 20 volt from peak to peak for a load C TOTAL of approx. 14.5 pF. <IMAGE>
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