GPIO output source resistance

[Rushd]

What is the source resistance for the GPIO pin when driven high and configured as following:

• Output, Standard 0.5mA drive, No pullup, S0S1
• Output, High 5mA drive, No pullup, H0H1

[Håkon Alseth]

Hi,

We do not have specification for this parameters, but by looking at the guaranteed voltage area for the output, you can do some simple calculation to find the resistance.

In both "High" and "Standard", we guarantee that the voltage shall be within VDD-0.3V when setting the output.

The equivalent resistance can then be calculated:

Re = delta(U) / I

For "Standard" 0.5 mA:

Re = 0.3 V / 0.0005 A = 600 ohm 

For "High" 5 mA:

Re = 0.3 V / 0.005 A = 60 ohm

Cheers, Håkon

[Håkon Alseth]

NP, always happy to help! :-)