A switching control circuit includes a serial-to-parallel converter, a
rewritable storage device, and a decoder. The serial-to-parallel
converter performs serial-to-parallel conversion for converting an
inputted first control signal into a first parallel signal, and outputs
the first parallel signal. The rewritable storage device has a write mode
and a read mode selectively switched over in response to a storage mode
switching signal, stores therein data of the first parallel signal in the
write mode, and outputs the stored data as a second parallel signal in
the read mode. In the read mode, the decoder decodes the first control
signal and the second parallel signal to generate and output a plurality
of element control signals to a plurality of elements, respectively. In
the write mode, the decoder holds the plurality of element control
signals generated in the read mode.