Testing subsystem for battery powered Smart Modules

Smart Module processor under test: current variable between 8mA and 15mA. All readings taken at 8am each day.

The measured battery performance is consistent with the Coppertop AA voltage vs. time graph provided in their datasheet. Remarkable end-of-battery life results: the subsystem maintained Vdd at 5.2V and current supplied >8.2mA while the voltage supplied by the 4 AA batteries declined to 2.15V at 4pm on the 18th! The last 2 hours saw a precipitous decline in Vdd from 2.8V to failure at 2.1V at 4:15pm.