Power Train Prototype and measurements

A project log for SoLoRa - Solar Powered always-on IoT sensor node

Unique, compact power conditioning enables always-on sensor monitoring and Long-Range radio (LoRaWAN) link for IoT applications.

Joe MillerJoe Miller 07/11/2018 at 21:300 Comments

This is the prototype of the power train for the project. I used this to measure its characteristics.

Power train prototype

In full sun I measured 90mA of charge current into my LiFePo4 battery when perpedicular to the Sun and 60mA. 30mA on a cloudy day and 23mA when tilted at 45-degrees to the apparent Sun direction.  500uA in shade, not pointing at the sky.  20mA of charge current was measured through a window in my house pointing at a blue sky (the Sun not in view).

The back-leakage from the battery storage cell to the circuit with no sun was ~1uA, ~6uA at dusk and dawn conditions.