A switch apparatus of the invention comprises a first input terminal, a second input terminal to which a second input signal having a level lower than a level of the first input signal is supplied, a first switch block for outputting the first input signal supplied from the first input terminal through a plurality of switching elements, a second switch block for outputting the second input signal supplied from the second input terminal through a plurality of switching elements; and a control terminal to which a control signal is supplied wherein the control signal controls the first switch block when outputting the first input signal, and controls the second switch block when outputting the second input signal, wherein the first switch block is configured to have a smaller number of switching elements than that of the second switch block.