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ENG-CANSAT-PICO-POWERING (voir la source)
Version du 3 novembre 2022 à 23:38
, 3 novembre 2022 à 23:38→Pico and Sparkfun Lipo Charger/Booster
Here how it works. Please note that {{underline|only the Pico Micro USB}} is used in this setup.
Here how it works. Please note that {{underline|only the Pico Micro USB}} is used in this setup.
{{underline|'''When Pico is plugged on a computer:'''}}
For sure, you can program and interact with the board.
On the powering aspect:
# The Pico and its 3.3V regulator are powered via USB
# The Pico VBUS pin is set to 5V
# The Pico VSYS pin is also at 5V. Thanks to the diode, the 5V VSYS does not inject current into the 5V output of the PowerBoost charger.
# The 5V VBUS (on the Pico) do power the PowerBoost on the USB pin. As a result, the PowerBoost does charge up the Lipo.
Summary: the Pico is running and the Lipo is charging.
{{underline|'''When Pico is UNPLUG from computer:'''}}
# The Pico VBUS is at 0V
# The Pico VSYS is at 0V (but this will change).
# The Pico regulator is not powered
# As the PowerBoost is running, it generates 5V on its '''5V Output''' Pin. The 5V push the current through the diode to '''VSYS'''
# The Pico VSYS now receives 5V (a bit lower due to the diode lost). So the Pico regulator is powered and generating 3.3V.
Summary: the Pico is running and the Lipo is discharging.
{{underline|'''How to power off:'''}}
To power-off the Pico when the USB is unplug on the Pico, we have the following options:
# Tied the '''Pico 3V3_EN pin''' to the ground : that disable the Pico but the Powerboost is still discharging and producing 5V.
# Tied the '''PowerBoost EN pin''' to the ground : this disable the PowerBoost which stops to power up the Pico. The best approach.
== Pico, PowerBoost and Cansat Kit ==
== Pico, PowerBoost and Cansat Kit ==