running SAMD21 at 1.8V

Development Boards
1

Hi there,

I’m trying to run Sparkfun SAMD21 mini dev board at 1.8v, but I was only able of running up to 2.2v.

Bellow that value the chip bricks (locks) in the last state.

I then thought it was the BOD33 limiting the voltage, but as it seems from the datasheet, that the default value is 0x07, meaning around 1.7v.

Is there something in the arduino or sparkfun core that limits the voltage to 2.2v?

thank you for your support

2

All input voltage runs through the AP2112K 3.3V Regulator (with the exception of Analog Input). The minimum rated voltage, as per the datasheet: https://www.diodes.com/assets/Datasheets/AP2112.pdf, is 2.5V. Perhaps, that could be the issue.