视频信号放大器的的设计.doc

PAGE 视频信号放大器的设计 摘要 视频信号指电视信号、静止图象信号和可视电视图象信号。视频信号可支持三种制式：NTSC、PAL、SECAM。放大视频信号是为了增强视频的亮度、色度、同步信号。将视频信号预处理电路输出的信号继续放大，以推动显像管阴极，并实现亮度控制，行、场消隐。视频信号放大器是放大视频信号，是用以增强视频的亮度、色度、同步信号。当视频传输距离比较远时，最好采用线径较粗的视频线，同时可以在线路内增加视频放大器增强信号强度达到远距离传输目的。视频放大器可以增强视频的亮度、色度和同步信号。 视频信号放大电路采用5个三极管，是一个5 MHz带宽的宽带放大器。信号施加输入端和通过 HYPERLINK /tech/dzq/200010070034/799314.html \t _blank C1采取的第一阶段，这是一个前置放大器和围绕第一级构成 。在第一级的输出直流耦合，第二级它放大信号加更，因为它们是直流耦合的前置放大器有几乎没有失真和放大是很高。最后，从第三级输出的信号是Q4及Q5的输出三极管。这两个三极管是相辅相成的，从他们的共同发射器的信号是从那里发送到驱动电路的各种设备的信号分配RC网络。该电路需要一个直流的 HYPERLINK /tech/ljq/200010230005/989732.html \t _blank 12V HYPERLINK /tech/jdq/200010110002/18851.html \t _blank 电源。 关键词：视频信号放大器；增强视频；直流耦合；失真； HYPERLINK /tech/jdq/200010110002/18851.html \t _blank 电源 Abstract Video signal is a television signal, still image signal and visualization television picture signal. The video signal can support three formats: NTSC, PAL, SECAM. Amplify the video signal in order to enhance the video luminance, chrominance, synchronizing signal. Continue to enlarge the output signal of the video signal preprocessing circuit to promote the CRT cathode, and brightness control line and field blanking. The video signal amplifier to amplify the video signal, is used to enhance the video luminance, chrominance, synchronizing signal. Video transmission distance is far, the best the coarse diameter of video cable, and can increase the video amplifier to boost the signal strength to achieve the purpose of long-distance transmission line. The video amplifier can be enhanced video luminance, chrominance and synchronization signals. The video signal amplifier circuit transistor 5 is a 5 MHz bandwidth broadband amplifier. Signal is applied to the input terminal and the first stage by the C1, which is a preamplifier and around the first stage.Output dc-coupled in the first stage, the second stage it is amplified signal add more, because they are dc-coupled preamplifier with almost no distortion and magnification is high. Finally, the signal is