A NON-LINEAR ANALOG-TO-DIGITAL CONVERTER FOR LINEARIZATION OF TRANSDUCER INPUT-OUTPUT RELATIONSHIPS

Analog and digital techniques for linearization of non-linear input-output relationship of transducers are briefly reviewed. The condition required for linearizing a non-linear function y equals f(x) using a non-linear analog-to-digital converter is explained. A simple technique to construct a non-linear digital-to-analog converter based on 'segments of equal digital interval' is described. The technique was used to build an N-DAC which can be employed in a successive approximation or counter-ramp type ADC to linearize the non-linear transfer function of thermistor-resistor combination. The possibility of achieving an order of magnitude higher accuracy in the measurement of temperature is shown.