Patent ID: 7043202

Claim:
A phase-selective type frequency modulator comprising: multiphase clock signal generating means for generating N-phase clock signals having phase differences from each others; control means for sequentially activating one of first group of clock selection signals indicating a clock signal to be selected from the N-phase clock signals outputted from said multiphase clock signal generating means, said first group of clock selection signals corresponding to said N-phase clock signals; edge appearance time adjusting means for adjusting a rising edge appearance time and/or a trailing edge appearance time of the first group of clock selection signals outputted from said control means to output second group of clock selection signals corresponding to the N-phase clock signals outputted from said multiphase clock signal generating means; and modulated clock signal generating means for selecting one clock signal from said N-phase clock signals in accordance with an activated state of said second group of clock selection signals outputted from said edge appearance time adjusting means to output the selected clock signal as a modulated clock signal.