FREQUENCY SWITCHING METHOD, FREQUENCY SWITCHING DEVICE, AND IMAGING APPARATUS

PROBLEM TO BE SOLVED: To provide a frequency switching method by which enlargement of a circuit scale can be suppressed and abnormal operation can be prevented from occurring when a frequency is switched during operation. SOLUTION: When a frequency of an output signal is switched to a target frequency, a phase frequency comparator 10, a charge pump circuit 11 and a multiplication setting circuit 14 are reset (S2), a multiplication number is switched to a multiplication number C1 corresponding to the target frequency (S4), and a frequency division number is switched to a temporary frequency division number 2N larger than a frequency division number corresponding to the target frequency (S5). Thereafter, reset states of the phase frequency comparator 10, the charge pump circuit 11 and the multiplication setting circuit 14 are released (S6), and the frequency division number is switched to a frequency division number N corresponding to the target frequency (S8). COPYRIGHT: (C)2008,JPO&INPIT