Two-wire, low component count soil temperature sensor

• Main Author: Sitter, Nicholas James
• Other Authors: Kruger, Anton
• Format: Others
• Language: English
• Published: University of Iowa 2011
• Subjects: Bidirectional; Low component; Parasitic; Pulse width modulation; Temperature; Two-wire; Electrical and Computer Engineering
• Online Access: https://ir.uiowa.edu/etd/1081; https://ir.uiowa.edu/cgi/viewcontent.cgi?article=2466&context=etd

A two-wire, low component count soil temperature sensor was developed. The sensor uses one wire for ground and the other wire is used for both power and communication. Pulse width modulation is used to send temperature measurements to the master, where the duty cycle is proportional to the temperature. The sensor parasitically powers itself from the bidirectional data line. In order to reduce the number of components necessary, a microcontroller with an internal temperature sensor is used. Finally, the sensor can receive data from the master on the bidirectional communication line, which is used for calibrating the sensor.