Accession Number : ADP002512

Title :   An Improved Method of Temperature Compensation of Crystal Oscillators,


Personal Author(s) : Wilson,J. S.

Report Date : 1983

Pagination or Media Count : 6

Abstract : A new method of temperature compensation of crystal oscillators has been developed. It is primarily intended for AT-cut crystal oscillators and offers advantages of higher stability, lower power consumption and smaller size compared with oscillators in current production. Compensation is achieved by generating a power series representation of the control voltage for a voltage controlled crystal oscillator. A bipolar integrated circuit has been designed which generates four voltages, each varying as a function of temperature. One voltage is constant while the others have a linear, quadratic and cubic variation with temperature. These voltages are similar in shape to the first four Chebyshev polynomials and the compensation voltage is obtained by summing the voltages in an operational amplifier. Prototype oscillators have been assembled which have a frequency tolerance of less than + or - 1ppm over the temperature band 85 deg C to -40 deg C. The current consumption of these oscillators is 1mA. (Author)

Descriptors :   *Crystal oscillators, *Temperature control, Integrated circuits, Stability, Frequency, Power series, Voltage controlled oscillators

Distribution Statement : APPROVED FOR PUBLIC RELEASE