ERROR PROPAGATION IN INTERFACE ELECTRONICS FOR PASSIVE SENSORS.

Contemporary interface electronics for passive sensors may be divided into three groups according to the output variable: frequency output, voltage output and pulse duration modulated output. The paper presents the basic principles of error propagation for only two groups. The error propagation depends mostly on the sensor properties ("m" coefficient) and on the structure of the interface electronics (nondifferential or differential one). For sensors with low "m" values the similarity of error propagation for both investigated groups has been found in spite of the great differences in their design. Specific properties of quasi-differential strictures - like bridges - are presented too.