A few years ago, Julian Ilett designed the original, PIC microcontroller based “PWM5” solar charge controller. He also experimented with an Arduino based version. You can find his videos here: https://www.youtube.com/channel/UCmHvGf00GDuPYG9D…
according to Julians schematic, arduined.eu designed a very small version, based on the 5V, 16MHz Arduino Pro Mini: https://www.arduined.eu/arduino-solar-charge-cont…
After I already designed and built two MPPT buck solar chargers, I wanted to try this very simplistic design.”

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