摘要 |
An existing analog two-wire transmitter (11) has a sensor module (35), and analog circuits (23) which provide an output representative of a sensed process variable, such as pressure, to a two-wire current loop (14). At least portions of the analog circuit (23) are removed and replaced with apparatus including a digital converter (52) that digitally calculates the transmitter output using the same current range in the current loop (14) and calculating corrections for obtaining linearity of the output. |