| 摘要 |
<p>PURPOSE: To provide a clock supply device which can supply an operation clock that synchronizes with the operation clock to a peripheral circuit at all times and is stable to the peripheral circuit even when the operation clock to a CPU is switched. CONSTITUTION: A reference clock is divided by a CPU frequency division part 17 to generate 1st and 2nd clocks. One of the 1st and 2nd clocks is selected by a CPU clock switching part 15 and outputted to the CPU 12, and also inputted to a peripheral circuit frequency division part 18. The peripheral circuit frequency division part 18 outputs 3rd and 4th clocks generated by performing frequency division as many times as predetermined and a peripheral circuit clock supply part 16 selects and supplies an operation clock of specific frequency to the peripheral circuit 13.</p> |
