Semiconductor integrated circuit and information processing system
US7668675B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 29, 2008 |
| Grant date | Feb 23, 2010 |
| Priority date | — |
| Expiry date | Jun 2, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K5/19
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In a semiconductor integrated circuit, a counter counts the number of high-speed clock signals that have been generated in a predetermined number of clock cycles of a low-speed clock signal. In synchronization with the low-speed clock signal, the semiconductor integrated circuit compares the counter value and a predetermined value, and judges whether the frequency of the high-speed clock signal has reaches a predetermined frequency. Since variations in the frequency become smaller as the oscillation of a high-speed oscillator stabilizes, the semiconductor integrated circuit detects that the oscillation is stable when the semiconductor integrated circuit has judged affirmatively a plurality of times.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.