Single Circuit Board Implementation of a Digitally Compensated SAW Oscillator (DCSO).
Abstract
A circuit, using standard 'off-the-shelf' components, for digital temperature compensation of a SAW oscillator was designed. This circuit was implemented on a single circuit board. A crucial component of the circuit, the AFIT IC, designed by four previous AFIT students and fabricated by NCR, failed to operate at a required frequency of 37 MHz. This caused an early halt to the project; however, several parts of the design were tested individually with good results. The portion of the circuit consisting of the D/A converter, op amp, and phase shifter was tested. For various addresses programmed on the D/A converter inputs, which simulated the output from the two EPROMs, a total phase shift of 107 degrees was obtained from the phase shift circuit. The thermometer and clock paths of the SAW device were made to oscillate at their respective resonant frequencies by introducing the proper amounts of phase shift and attenuation into the feedback loops. The thermometer and clock resonant frequencies were 309 MHz and 298 MHz respectively.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1983
- Accession Number
- ADA138313
Entities
People
- J. W. Mcguire
Organizations
- Air Force Institute of Technology