Low-Power and High Precision Sensing Circuit for a Three-Channel Electrochemical Sensor

A discrete, compact, low-power sensor readout circuit that can simultaneously handle two current measurements, and one voltage measurement. This work provides a compact, low-power sensor architecture, with the intent for the serial readout to be replaced with a low-power radio frequency transmitter for continuous monitoring. The proposed circuit is highly precise with an average current draw of 21 micro amps for a sampling frequency of once per minute. The target application is livestock health monitoring, which would be done by placing the sensor and circuit inside of a cow's rumen to monitor changes in pH, lactate, and VFA levels to catch metabolic disease early.