No Warmup Crystal Oscillator
Abstract
During warmup, crystal oscillators often show a frequency offset as large as 1 part in 10 to the 5th power. If timing information is transferred to the oscillator and then the oscillator is allowed to warmup, a timing error greater than 1 millisecond will occur. For many applications, it is unsuitable to wait for the oscillator to warmup. For medium accuracy timing requirements where overall accuracies in the order of 1 millisecond are required, a no warmup crystal concept has been developed. The concept utilizes two crystal oscillators, which are used sequentially to avoid using a crystal oscillator for timing during the trauma of warmup. One oscillator may be a TCXO which preserves timing information during the warmup of the second crystal oscillator which has a much higher frequency accuracy once warmed up. This paper will show the accuracy achieved with practical TCXOs at initial start over a range of temperatures. A second design utilizing two oven controlled oscillators will also be discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1981
- Accession Number
- ADA494478
Entities
People
- D. H. Phillips
Organizations
- United States Naval Research Laboratory