Rabotnik & Ding
Hey Rabotnik, Iāve been looking into lowācost solarāpowered microcontroller clusters for remote data logging. Ever tinkered with something like that?
Yeah, Iāve built a few of those. Start with a cheap MCU like the ESP32 or STM32, then add a solar panel that can give at least 2ā3āÆW. Put a charge controller in the middle, maybe a small battery like a 12āÆV leadāacid or a lithium pack. Keep the firmware lean ā just log the sensor data, timestamp, and push it when WiāFi is available. Use a lowāpower mode between samples so you donāt drain the battery. The trick is to size the panel and battery for the worstācase daylight, and keep the code simple so it can run on a single core. I can show you the schematic if you need it.
Sounds solid, but a few tweaks could shave off weight and cost. If youāre using the ESP32, the builtāin regulator is already pretty efficient; you might get away with a 4.5āÆV buckāconverter instead of a full charge controller if youāre powering the board directly from the panel. For the battery, a 3.7āÆV LiāPo with a 10Ah capacity is lighter than a 12āÆV leadāacid and works nicely with the ESP32ās 3.3āÆV logic after a simple LDO. Make sure the panelās peak voltage matches the regulatorās input range, otherwise youāll waste energy. If you send me your schematic, I can point out any hidden drains or places where you could consolidate components.
Nice tweak. Iāll drop the heavy charge controller and go straight to a 4.5āV buck. The 10Ah LiāPo will keep the weight down and the ESP32 will handle the 3.3āÆV with an LDO. Just make sure the panelās peak is above the buck input, or the regulator will choke. Send me the current layout and Iāll spot any extra leakage or parts we can trim.We followed instructions.Got it, letās keep it lean. Send the schematic and Iāll hunt for any sneaky drains or redundant parts.
Sure thing, just drop the schematic file or a link to a CAD view and Iāll go through it. Make sure youāve got the panelās max voltage around 5.5ā6āÆV so the buckās not starved, and doubleācheck that the ESP32ās deepāsleep pins are actually in lowāpower mode between samples. Iāll flag any stray traces or unneeded decouplers once I see the layout.
Got it. Iāll fire up the CAD file, zip it, and drop the link in the chat. Iāll keep an eye on that 5.5ā6āÆV window and doubleācheck the deepāsleep pins. Look forward to your feedback on the layout.
Sure thing, just drop the link when youāve got it and Iāll take a look. Let me know if you need anything else in the meantime.
Alright, pulling up the CAD file now. Iāll zip it and drop a link in this chat as soon as itās ready. Just let me know if you need any tweaks or a quick runāthrough of the deepāsleep setup before that.