Sensor system with one-chip microsystem

The paper describes design, construction of and results obtained with a contactless measuring system using a passive integrated resonance circuit. The system is intended for measurement of small pressure variations and contactless information transmission. It is based on the principle of variation of the resonance frequency of a single-chip integrated tuned circuit with measuring capacitance. The one-chip resonant circuit has been realised as a monolithic integrated sensor in CMOS technology. The dimension is approximately 10 mm/sup 2/. The active part has the form of an absorption resonance frequency meter. Measurement, control, approximation, computation and result processing are performed on a PC. The paper proper deals with the theory of system design, electronic circuit connections, parasitic capacitances effects calculation, fabrication technology of the integrated passive resonant circuit, result evaluation and techniques of PC-controlled absorption meter.