Digital converter apparatus for improving the output of a two-wire transmitter

摘要: An existing analog two-wire transmitter has a sensor module, an excitation circuit, and detector circuit which provides output representative of sensed process variable, such as pressure, to current loop. The detection is removed replaced with apparatus including digital converter that digitally calculates the transmitter's output. improved by calculating correction for linearity. may also be replacement circuit. can energized in series control energization current. A charge pump coupled loop balance provide electrical span zero adjustments.