A successive approximation register including a digital-to-analog conversion circuit, a sample-and-hold circuit, a comparison circuit and a SAR logic control circuit is provided. The method and system determines whether an interlaced video stream is a normal mode video stream or a converted mode video stream. The plurality of fixing members fix the fixing parts of the pressing member to the sub-board, and fix the sub-board to support members at positions that are closer to the connector than the main part is.