GPIO voltage levels


I’ve been looking through the Edge schematics and other documents. I’d like to work out which Edge fingers / Edge V pins are 3.3V, which are 1.8V and which are the weird 3.0V ones. This isn’t documented anywhere as far as I can see, although the schematic shows clearly which SoC lines each finger/pin connects to.

Is there a good place to look to get a list of which RK3399 GPIO/SPI/I2C/etc. lines are which voltage? I assumed I could find this info somewhere in the RK3399 data sheet or TRM, but I couldn’t locate it when I browsed through.


Following up to myself, I’m guessing that the GPIOs that are brought out on the Edge-V header are 3.3V apart from the ADCs at 1.8V, or it wouldn’t be compatible with the VIM2.

However, I’d really appreciate a pointer to a reference where this is documented, and see the voltage domain of the many other GPIO/I2C/SPI lines exposed on the Edge fingers. It’s quite an important thing for buyers to be aware of: if they shove 3.3V into a 3.0V or 1.8V GPIO, they’ll probably fry their brand new RK3399…