A control device includes a control IC that receives power supply from a power source unit activated by a first signal, and that is configured to control driving of the power source unit, a first signal acquisition unit configured to acquire the first signal, a detection unit configured to detect rising and falling of the first signal, a second signal output unit configured to output a second signal when the falling of the first signal is detected by the detection unit, and a lowering unit configured to lower, according to the second signal output from the second signal output unit, a voltage value of a terminal of the power source unit, to which the first signal is to be input, to a predetermined value or less for a predetermined period of time set in advance.