Electronic pressure switch has first operational amplifier whose output signal depicts negatively pressure dependence, without changing overall gain factor of instrument amplifier based on certain conditions relating to resistors

摘要

The switch has a resistance measuring bridge (3) that is provided with an instrument amplifier (4) implemented with operational amplifiers to which measuring bridge signal is supplied. The outputs of operational amplifiers are connected with resistors (9,10) and a comparator (5). The inverting inputs of operational amplifiers are connected with parallel switched resistors. The output signal of first operational amplifier depicts significant negatively pressure dependence, without changing overall gain factor of instrument amplifier based on certain conditions relating to resistors. An independent claim is included for a method for operating pressure switch.