Hi everyone,
I have an Arduino MKR NB 1500 connected to a QTPY SAMD21 using a STEMMA cable. The QTPY runs using the power from the Arduino. Is it safe to use the QTPY with BFF charger and a battery at the same time it's connected to the Arduino? Thanks,
Mike
QT PY with STEMMA power and LiPoly charger BFF
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- jcurryhydro
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- dastels
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Re: QT PY with STEMMA power and LiPoly charger BFF
Not likely. You'd have 2 power sources connected together which is never good.
More concerning is having the two boards connected via I2C/STEMMA. How are they wired?
Dave
More concerning is having the two boards connected via I2C/STEMMA. How are they wired?
Dave
- jcurryhydro
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- Joined: Sun Mar 22, 2020 11:39 am
Re: QT PY with STEMMA power and LiPoly charger BFF
Hi Dave, thanks, it sounds like I will need to find a different approach - When the Arduino is powered on, I want it to communicate with the QT PY and also be able to remove power to the Arduino for short periods while the QT PY stays on. I wired them using Adafruit item #4483 - QT to Arduino MKR 100mm cable.
Mike
Mike
- dastels
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Re: QT PY with STEMMA power and LiPoly charger BFF
You can have them communicate via I2C (one side will need to be in peripheral mode) but not powered. Just connect SDA, SCL, and ground.
Dave
Dave
- jcurryhydro
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Re: QT PY with STEMMA power and LiPoly charger BFF
I am using the same battery to power both the Arduino and the BFF charger. The QTPY controls the EN pin on an Adafruit powerboost 500 that powers the Arduino with a USB cable. The wiring from the battery will connect in parallel to both the powerboost 500 and the BFF (see image). Removing the power wire from the I2C cable is a good idea, thanks,
Mike
Mike
Please be positive and constructive with your questions and comments.