| 摘要 |
A delay circuit is to produce a delay timing which is larger than one cycle time of a reference clock while the resolution of which is smaller than the one cycle time of the reference clock. The delay circuit includes a coarse delay circuit for producing a borrow signal having a delay time which is an integer multiple of one cycle time of a clock signal supplied thereto, a divider for dividing the frequency of the reference clock to produce the clock signal, a flip-flop circuit for delaying an incoming signal by one cycle time of the reference clock, a re-timing circuit for receiving an output signal from the flip-flop circuit and producing a coarse delay signal in synchronism with the reference clock, a decoder for receiving the borrow signal from the coarse delay circuit and selectively providing the borrow signal to either the flip-flop circuit or the re-timing circuit, and a fine delay circuit for adding a fine delay time which is smaller than the one cycle time of the reference clock to a coarse delay signal from the re-timing circuit. |
