nRF52840 GPIO Drive Strength; how to interprete "Standard drive, low frequency I/O only"

[rodims]

I need to decide which pins I should use for 3 LEDs (5 mA each).

The "recommended usage" column in the documentation for the nRF52840 in Table 1 Pin assignements 

mentions "Standard drive, low frequency I/O only" for many pins. But it does not distinguish between "drive strength" and "frequency" here. 

I'm aware about the differences between standard and high drive, and also that I should not use these pins for higher frequencies > 10 kHz. 
( I will use RF radio )

But my problem is simply that I'm not sure how to read "Standard drive, low frequency I/O only"
Should it be read as "Standard drive only OR low frequency I/O only" ? 

I.e. should I not use these pins for my (more or less static) LEDs, if I want to configure High-Drive ? 

[Simonr]

Hi

"Standard drive, low frequency I/O only" is the tag of the pins that are close to the radio on the nRF52 series chips, and has this tag as they may interfere with the radio if they're set to use anything other than standard drive or low frequency while the radio is running. So if you're planning to use the radio at the same time as the LEDs are running and configured in for example high drive, I suggest you do not use these pins for that purpose. 

Best regards,

Simon

[Ron]

Hi

Is it recommended to use them for i2c? at what max Freq?

Thanks!

Ron

[Simonr]

Hi Ron

This is mentioned in the note on page 580 on nRF52840 PS. https://infocenter.nordicsemi.com/pdf/nRF52840_PS_v1.8.pdf 

"Note: For more information on standard drive, see GPIO — General purpose input/output on page 151. Low frequency I/O is a signal with a frequency up to 10 kHz."

Best regards,

Simon