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Xinyuan-LilyGO / LilyGO-T-SIM7000G

LilyGO T-SIM7000G
https://pt.aliexpress.com/item/4000542688096.html
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Which pins to read solar and battery voltage levels and expected value ranges? #174

Open num-lock opened 2 years ago

num-lock commented 2 years ago

I keep reading about measuring the battery and solar voltage levels (documentation, issues, product pages) but I can't figure out which pins to use and I am not good at reading schematics. Can anyone tell me which pins to read in as analog and what values to expect for each? I assume there are some resistors in place so I guess there is some standby drain and current as well on the battery?

Also might be worth adding that to the documentation.

rtrombetta commented 1 year ago

In schematic on page 2 TEST section, for VBAT there is a voltage divider formed by R62 and R63 which appears to split the VVBAT voltage and is connected to IO35. There is another voltage divider formed by R64 and R65 that seems to divide the VSOLAR voltage and is connected to the VP (IO36). But... I think these components don't exist on the board and this is just a suggestion to build a circuit to measure the voltage, because I put a multimeter on the IO35 pin and I couldn't measure any voltage. As I don't have and I couldn't find the board layout on the internet, it's hard to find out if they exists.

DevinCarpenter commented 1 year ago

I couldn't get anything to work for a voltage divider with the built in components on this board. For now I have built my own voltage divider to use to measure the battery. Here's a link to my Tinkercad voltage divider here if you'd like to test it out and build one for yourself.