Programmable AC Current Source Using Mixed Signal Microcontroller for Reliable and Low Cost Soil Conductivity Sensor

Abstract:

In this paper, a digitally programmable AC current source is introduced. The proposed scheme provides the ability of digitally setting the output current frequency and amplitude. The realization method, based on commercially available devices, employs digital-to-analog converter (DAC), and voltage controlled current source (VCCS). The proposed circuit offering high accuracy and linearity is suitable for measuring soil conductivity. Experimental results showing the circuit performances are also included. The developed source provides acceptable precision i.e. absolute percentage error of 3%. The covered conductivity range indicates the importance of such a low cost and reliable source.

• Periodical: Advanced Materials Research (Volumes 403-408)
• Pages: 3980-3987
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.403-408.3980
• Online since: November 2011
• Authors: Babankumar S. Bansod, Kunal Bansal, Priyank V. Hirani, Ritula Thakur
• Keywords: Conductivity Sensor, Difference Amplifier, Soil Conductivity, Voltage Controlled Current Source

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