Patent ID: 6281943
Filing Date: 2001-08-28
Classification: H04N

Abstract:
A video pre-amplifier for use in a cut-off control circuit, comprising:a first adder for adding a video input signal to a clamping signal;an amplifier for receiving an output signal of the first adder and amplifying such signal to generate an amplified signal as a video output signal;a second adder for adding a first control signal to a brightness control signal;a comparator for comparing an output signal of the second adder with the video output signal from the amplifier and outputting a compared result as the clamping signal; anda switch circuit for receiving control data and generating a bus control signal according to the control data;wherein, the switch circuit outputs the bus control signal as the first control signal, or outputs a zero value as the first control signal and the bus control signal as a second control signal.