Temperature control of thick-film printed heaters

Abstract

Electronic circuitry powered from a single 24 V supply, based upon a Wheatstone bridge for controlling the temperature of planar thick-film platinum heaters, has been developed. A novel circuit modification was introduced to control the rate of temperature rise when switching on from cold without detracting from the response to convective perturbation at the operating temperature. Gas sensors operating at temperatures up to 900 degrees C represent an important application of this technology.