A new architecture for non-linear analogue-digital conversion

A modified architecture is proposed for the non-linear analogue-digital conversion of a transducer response. It is proved that by making use of a dual-slope A/D converter and by changing the clock frequency fed to the A/D converter during the deintegration period and blocking some of the pulses during this period, a nonlinear A/D conversion can be achieved. This method was used to linearize a Pt-PtRh thermocouple response and excellent results were obtained. Further, it is proved that the frequency change depends only on the maximum slope of the transducer response that is to be corrected.