Design of a planar interdigital capacitor for pressure measurement

Abstract

This paper presents the design and fabrication of a planar interdigital capacitor (IDC) for pressure measurement. This design uses the basic principle of capacitor. A planar interdigital capacitor for pressure measurement is fabricated from a single-sided FR-4 printed circuit board (PCB) and constructed by dry film technique. The experimental of a planar interdigital capacitor for pressure measurement used an LCR meter to input a voltage of 2 V, frequency 100 kHz and recorded the capacitance obtained from the test and use Table Top Universal Testing Machine Force Test (TUTMFT) to create pressure. The test is repeated five times at a pressure of 5–70 N; each time, the pressure will increase by 5 N until it reaches 70 N, and so on until 5 times have been completed. The results of the capacitance of the pressure applied to a planar interdigital capacitor for pressure measurement at created found the capacitance changed from 5.3183 pF dropped to 5.2889 pF, which decreased according to the weight of the pressure used, the test had an correlation coefficient (R2) was 0.9904, sensitivity was 0.0802 pF/N, accuracy of 0.991 (99.1 %) and precision was 99.94 %. The results show that the designed and fabrication of a planar interdigital capacitor for pressure measurement has achieved excellent experimental results. A planar interdigital capacitor for pressure measurement can be applied to microcontroller for weight measurement or related industrial pressures. Moreover, the advantage of a planar interdigital capacitor for pressure measurement is that it has a simple structure uncomplicated installation and is inexpensive