| 摘要 |
A frequency divider section generates a frequency-divided clock RSELO by dividing the frequency of an internal clock LCLK, which lags behind an external clock in phase, and generates a delayed frequency-divided clock RSELI by delaying the frequency-divided clock RSELO. A signal input from the outside in synchronization with an internal clock PCLK which lags behind the external clock in phase is held in a latch circuit in synchronization with the delayed frequency-divided clock RSELI. Then, an output signal of the latch circuit is read into a latch circuit in synchronization with the frequency-divided clock RSELO and is output as a signal which is synchronized with the internal clock LCLK. In addition, a frequency divider section includes a variable divider which divides the frequency of the internal clock LCLK by a predetermined divide ratio which can be changed.
|
