@msfujino, @hobbya
This is interesting information which I didn’t find so far.
But this confuses me even more, as when calculating the current which the battery will be charged based on the ISET-resistor (2k7) we get lower values than reported from the thread linked above from @msfujino. So, we now even have contradictory information.
@PJ_Glasso
Interesting to know would now also be, if this Note 1 is really only applicable on the Charge Mode or should be used on the Standby Mode as well. Because under Charge Termination it is noted, that when the chip enters Standby Mode (which I guess happens when no battery is connected but ISET is still pulled to GND) the input current drops to 200 uA, which is well above the values in the table.
This then could actually be this vampire-current. I did check with a second XIAO, which behaves exactly the same.
And regarding the battery level read: they at least justify the lack of implementation. And I guess, an additional voltage divider would mean one more time some more current.