Adafruit Feather M4 Express, Руководство пользователя

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ENable pin
If you'd like to turn off the 3.3V regulator, you can do that with the EN(able) pin. Simply tie this pin to Ground and it will
disable the 3V regulator. The BAT and USB pins will still be powered
Alternative Power Options
The two primary ways for powering a feather are a 3.7/4.2V LiPo battery plugged into the JST port or a USB power
cable.
If you need other ways to power the Feather, here's what we recommend:
For permanent installations, a 5V 1A USB wall adapter (https://adafru.it/duP) will let you plug in a USB cable for
reliable power
For mobile use, where you don't want a LiPoly, use a USB battery pack! (https://adafru.it/e2q)
If you have a higher voltage power supply, use a 5V buck converter (https://adafru.it/DHs) and wire it to a USB
cable's 5V and GND input (https://adafru.it/DHu)
Here's what you cannot do:
Do not use alkaline or NiMH batteries and connect to the battery port - this will destroy the LiPoly charger and
there's no way to disable the charger
Do not use 7.4V RC batteries on the battery port - this will destroy the board
The Feather
is not designed for external power supplies
- this is a design decision to make the board compact and low
cost. It is not recommended, but technically possible:
import board
from analogio import AnalogIn
vbat_voltage = analogio.AnalogIn(board.VOLTAGE_MONITOR)
def get_voltage(pin):
return (pin.value * 3.3) / 65536 * 2
battery_voltage = get_voltage(vbat_voltage)
print("VBat voltage: {:.2f}".format(battery_voltage))
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