FIG. 5A shoWs an example of a ramp signal generating
circuit. The ramp signal generating circuits 3 and 11 are
fundamentally implemented by the same circuit. Remember
that, hoWever, the control signals for controlling the sWitch
S3 are different from each other in this case. The control
signal for the ramp signal generating circuit 3 is a pulse
signal from the oscillator 2, While the control signal for the
ramp signal generating circuit 11 is an output of the latch
circuit 5.