About this component
Makes the 3.3 V rail for the module and the 3V3 header pin. Wi-Fi transmit bursts draw several hundred milliamps, so a weak or overheating regulator shows up as brown-out resets when Wi-Fi starts. Feeding a separate 3.3 V supply into the 3V3 pin bypasses it. Labelled U2 on the schematic.
What it does on this board
Supplies the 3.3V module rail from 5V USB.
Pinout & readings
Pinout and readings are for members
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- The full pinout — 4 pins with what each one does
- Datasheets