REFERENCE'S ACCURACY IN VIRTUAL FREQUENCY-TO-CODE CONVERTERS

摘要

The methodology and experimental results of the researches for thermal instability of reference clock generator in microcontroller based frequency-to-code converters with virtual channel are described in the Paper. The temperature uncertainty of the frequency and time references, distribution laws and correlation factor of their errors were determined in the experiments. The maximum relative temperature error of the frequency reference is +- 11.5 10~(-6), and the maximum temperature error of the time reference is +- 0.38 10~(-6). The total relative error of the "measurement standard" in the microcontroller based frequency-to-code converters is equal to +- 10.9 10~(-6). The obtained results are used at research of the limiting metrological characteristics for microcontroller based measuring instruments of frequency/time parameters with virtual measuring channel.