Abstract
This paper describes a low-cost realization of a precision capacitance measurement instrument. The method is based on synchronous modulation and demodulation operating at a frequency of 100 kHz. A two-channel multiplying digital-to-analogue converter is used to generate a sinusoidal drive voltage and to perform multiplication with the demodulation signal. The modulation and demodulation signals are generated using a direct digital synthesizer, which is implemented using a field programmable gate array. Experimental results show a reproducibility of better than in the range from 50 pF to 600 pF.
| Original language | English |
|---|---|
| Pages (from-to) | 510-517 |
| Number of pages | 8 |
| Journal | Measurement science and technology |
| Volume | 9.1998 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 1 Jan 1998 |