I'm working on a project with the RPi Pico that makes use of both the UARTs and has two LEDs attached to other random-ish GPIO pins. The LEDs will probably be turned on for the majority of time that the Pico is powered on.
I wish to add a mechanism to the firmware that lets the user configure the GPIO drive strength of the UARTs, as this should make certain baud rates more reliable through longer cables. However, I noticed that if I add the option to set both the TX and both the RX pins to 12mA, then we get a total of 48mA that may be used by all four of them at any given moment. Add the 2mA each LEDs on top, and we hit a total of 52mA of current at 3.3v that may flow out of the Pico's GPIO pins at any given moment.
This is above the maximum specified by the datasheet which is 50mA. I do not wish to damage the Pico or shorten its lifespan, so I want to make sure that setting 12mA drive strength on four of the UART pins along with other loads doesn't present a risk.
P.S. is there a real benefit to increasing drive strength to 12mA for UARTs or am I misunderstanding the effects it has? My understanding is that stronger drive strength produces cleaner, more square-like signals, which we need when dealing with baud rates as high as 3000000 (which my project will use).