Temperature compensated clock
US5644271A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1996 |
| Grant date | Jul 1, 1997 |
| Priority date | — |
| Expiry date | Mar 5, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L1/027
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A temperature compensation system includes a first oscillator to generate a number of pulses which vary from a desired frequency as a function of temperature of the first oscillator. The system also includes a second oscillator to generate digital pulses at a corrective frequency which is greater than the desired frequency. A sensor provides an temperature signal for the first oscillator. A digital memory has a digital error table addressable by a signal corresponding to the temperature signal to provide a number of pulse errors corresponding to temperature error for each of the number of pulses. Each pulse error is a function of the corrective frequency and a temperature versus frequency characteristic of the first oscillator. An accumulator receives each pulse error to generate a cumulative error corresponding to one of the number of pulses. A variable delay device counts a quantity of corrective pulses from second oscillator to provide a delayed output pulse in accordance with the desired frequency. The quantity of corrective pulses is a function of the cumulative error signal received from the accumulator. The converter, memory, accumulator and delay device may be part of a mic…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.