A circuit device comprises: a circuit board on which a plurality of signal lines transmitting a signal, and spare wirings intersecting the signal lines while being insulated therefrom and transmitting a signal if at least one of the signal lines has a defect are arranged; and a plurality of amplifiers each of which has an input terminal to which the signal is input, an output terminal amplifying the signal input to the input terminal and outputting the amplified signal, and a control terminal to which a signal for controlling a turn on or off of an amplification operation is input. The spare wiring includes an input-side spare wiring connected to the input terminal, and an output-side spare wiring connected to the output terminal.