A2337 2020 MacBook Air

A2337 (820-02016) MacBook Air

=== **Important** MacBook logic boards with a M1 processor may display 20v, 0.01 amps as measured on a USB-C amp meter if the board is out of the enclosure with the display disconnected. This is normal and is a operating characteristic of these boards. The device may be fully booted into an operating system with this amperage due to the M1's power conservation features. ===

820-02016 Power Sequence
Once a valid external power source (Charger or battery) is connected, the following rails will come online.

PPBUS_AON- Normal voltage ~12.6 - 13.1. Produced from the ISL9240 (U5200) that uses PPDCIN_AON_CHGR_R as its VIN.

PP3v8_AON_VDDMAIN- Normal voltage is ~3.8v. Produced from U5700 that uses PPBUS_AON as its VIN.