An RC Logarithmic Converter-Digitizer

Theoretical considerations and experimental data support the suggestion that high accuracy of conversion and long-term stability could be obtained with a logarithmic RC converter-digitizer. The operation of the proposed converter is based on time measurements of the exponential voltage decay across a linear RC network. Linearity error of this converter, built with commonly available and noncritical components, was found to be less than 0.05 percent of full scale for a two-decade operation.