I am sorry to be so thick, but I don’t have an electronics background, and I don’t understand your arguments.
My objective is the low quiescent current that newer battery-powered ESP devboards are designed for, by utilising the LiPo connector and voltage measurement built into the ESP32 FeatherS3 (or Firebeetle 2, or other) board. This should also reduce parts count and complexity.
Is this better ?
The Sunflower SPM has NO LOAD - all it is doing is charging the LiPo battery … by pushing current out the SPM’s battery connector. Does it matter to the ESP32 whether electrons it receives are coming from the battery or from the SPM ? As long as the voltage & current isn’t higher than a LiPo might supply, I assume not.
I am not trying to operate without any LiPo battery - but my previous attempt using the Sunflower SPM (as in the example Robert quotes) required two batteries.
Robert, what circuitry is between the Sunflower SPM’s “Li Battery IN” terminal block and JST connector ? I assume none. And how does the battery get charged if it is an INPUT only ?
As for the third image…
- I don’t understand how my ESP32 is acting as a second battery, which looks to be the reason for the “OR” you pointed out ?
- The microcontroller shown is connecting by USB; however this requires a second LiPo battery and more conversion losses …
The solar panel is connected to the Sunflower SPM and charging it’s LiPo - which is converted to 5V and passed to the ESP32 to charge it’s LiPo - which is used by the ESP32. This seems excessive conversion inefficiencies and unnecessary expense.
Robert I am still open to your suggestion of what is the right device to connect a solar panel safely to the 5V input of an ESP32 to charge the battery.
