Apparatus and methods for estimating a sleep clock frequency
US7529531B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 2005 |
| Grant date | May 5, 2009 |
| Priority date | — |
| Expiry date | Mar 26, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D30/70
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Apparatus and methods for estimating the frequency of a sleep or slow clock using a fast clock, such as a temperature compensated crystal oscillator. The disclosed apparatus include an estimator having a first counter that receives sleep clock synchronized pulses issuing each cycle of the sleep clock period, yet are synchronized to a fast clock. The slow clock synchronized pulses are counted up to a predetermined number; whereupon a full count signal is issued. A second counter receives the full count signal and increments each time the full count signal is received. A third counter counts fast clock cycles until the full count signal occurs. Based on the number of counts of the slow and fast clock cycles, the frequency of the slow clock may be determined using only the domain of the fast clock for performing the measurement thereby tying accuracy of the measurement to the accuracy of the fast clock. The disclosed apparatus also include an integrated circuit and a transceiver employing the disclosed estimator. Corresponding methods are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.