Abstract: This application note presents a simple, low-cost way to add the sync signal onto the green channel for standard-definition video. In some video applications, the signal sources deliver RGB signals and a composite sync signal. The RGB signals contain no video sync. At the receiver side, some low-cost video decoders do not have a stand-alone composite sync input; they only accept the sync signal with the video signal. Adding the sync signal onto the green channel for such an application requires a "sync on green" circuit. There is a simple, low-cost way to add the composite sync onto the green channel for standard-definition video. The circuit in Figure 1 uses the MAX9589 to add the composite sync to the green channel, and generates the standard RGB signals at each output. For example, consider a 0.7VP-P green signal input and a 0.3V composite SYNC signal input from the video sources that have 75Ω terminations. From Figure 1 the output signal at the green channel after the MAX9589 is 1VP-P. For the 0.7VP-P R and B input signals from the source, the output signals after the MAX9589 are 0.7VP-P. There is an advantage to using the MAX9589 in this application. The MAX9589 can be used as an anti-aliasing filter in front of the video decoder and, thus, improves the video performance. Figure 1. Schematic of a sync on green circuit. Figure 2. Input and output waveforms from the circuit in Figure 1. 相关型号   APP 4116: Sep 21, 2007 MAX9589 单、双、三和四通道标清视频滤波放大器，提供交流耦合输入缓冲器 完整的数据资料 (PDF, 892kB) 免费样品 自动更新 需要自动接收最新发布的应用笔记吗？请订阅EE-Mail™ (English only)。 我们期待您的反馈！ 喜欢？不喜欢？有待改善？或为我们提供建议？请与我们联系 — 我们将根据您的意见或建议改善我们的工作。 网页评价或提供建议   下载，PDF格式 (46kB)  AN4116, AN 4116, APP4116, Appnote4116, Appnote 4116