julius it occurred to me from your comments that you may have been reviewing the wrong PCB3 schematic, as the latest revision PCB3 includes a 4A buck-boost converter that ups the 3.8-4.2v battery output to 5.0V.  could you confirm that you've been reviewing the schematics that include a TPS63020, the BQ24193, and the BQ27542?

l.

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