Abstract: In a sampling circuit for a driving circuit for driving an active matrix circuit having signal lines in an active matrix type liquid crystal display device, two switches are connected with each other in series. Further a connection point between two switches is connected with a constant voltage input terminal through another switch or a resistor, to reduce a voltage applied to the TFTs constructing two switches and to perform at high speed operation in the TFTs. When sampling is not performed, the two switches are turned off and a constant voltage is applied from the constant voltage input terminal to the connection point.