Hello All
Looking at the electronic layout I have the impression that the pin labelled 3V3 can drive some small sensors ( XC6206P332MR is providing 200 mA). Is it correct that the 3V3 pin is actually an output? Does anyone knows this more precisly?
Regards, JuergL
Hi JuergL
After you connect the XIAO with a USB cable to your computer or a power source, the 3V3 pin will be powered and you can use it to feed this power to sensors. However, I am not sure about the max current available
Hi daaeed
Thanks for your reply. Then the CX6206… is really an output. This helps and makes my life with the Xiao easy 
I have 10 uF tantalum and 0.1 uF thin film capacitors on the 3.3V pin and using that output to power an I2C 20x4 LCD display and RTC (DS 3231) dev board with no issues whatsoever.
Hi Roussel,
I am curious to know why you are attaching an external RTC chip (DS 3231) when the SAMD21 has a built in RTC that has a clock & calendar mode?
Cheers, Brian.
