Serial Voltage

Hello,

On the OPENIMU300XX Eval Kit, are the serial interface 3.3v or 5v?

I am connecting GNSS and need to ensure I have the correct reference voltage for the GNNS device communication.

Is there a 3.3v or 5v output reference on the OPEN IMU?

I looked at the documentation and reviewed schematics, maybe I missed something?:
https://openimu.readthedocs.io/en/latest/300ZI/spi-uart.html
https://openimu.readthedocs.io/en/latest/300ZI/pinout.html#connector-pinout-including-gps-sensor-interface

Thank you!

the serial interface use 3.3v.
we supply 3.3v out by P2 area on board, current < 500mA.