Hello Kirin, I actually managed to measure the current through the 100pF cap. I took a 4.1 Ohm resistor in series and measured directly over it with my scope probe (short leads - 10mm). I got a short pulse like waveform at 44mV pk-pk which gives 10.7 mA at the peak of the pulse which duration is about 50 to 100ns... This is more than the 4mA maximum spec, so I assume there should be a series resistor. I will use 1k since this is already in the BOM. These are static IO signals turned on/off occasionally. Nevertheless, this pulse current must be supplied by the external decoupling capacitors - so in order not to stress them and cause brownout, I assume best practice is to use a series resistor. I guess the actual question to be answered is if it is OK/safe to allow short pulses of higher than 4mA as IO load? Thanks for the data! Regards, HC
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