A 0.1 ppm Successive Approximation Frequency-Temperature Compensation Method for Temperature Compensated Crystal Oscillators (TCXO)
Computer Science and Information Engineering, World Congress on (2009)
Los Angeles, California USA
Mar. 31, 2009 to Apr. 2, 2009
In this paper, we present a high accurate frequency-temperature compensation method for Temperature Compensated Crystal Oscillators (TCXO) which can achieve 0.1 ppm frequency stability over a wide temperature range from -25˚C to 85˚C by using 1-bit successive approximation differentiated interpolation. By applying a frequency-temperature compensated digital binary word to a digital frequency synthesizer, the generated frequency signal is controlled so as to be temperature compensated. The presented method can be also used for the crystals with abnormal frequency-temperature curve such as with abrupt frequency jump points. Compared to the traditional look-up table method, the presented method can dramatically reduce the storage cost to about 5%. The presented method has been implemented into the Xilinx FPGA and CMOS standard cell ASIC. The test result shows that 0.1 ppm frequency-temperature stability can be achieved with a temperature sensitivity of 0.5˚C.
TCXO, Successive Approximation
M. Zhang and W. Cao, "A 0.1 ppm Successive Approximation Frequency-Temperature Compensation Method for Temperature Compensated Crystal Oscillators (TCXO)," 2009 WRI World Congress on Computer Science and Information Engineering, CSIE(CSIE), Los Angeles, CA, 2009, pp. 493-498.