If the chip is "in air", the only charge it can unload or accept is equal to its capacitance. Not much current, not much energy. If something in it is grounded though, all the charge from the source of rather big capacitance (i.e. your body) will flow through it, burning it.

In the thesis work, I had to replace the dev. board because the old one was destroyed by ESD. Now the setup:
There are 2 12V batteries attached to amplifier driven from DAC, current from one of them going through a regulator to the board, there is a board with 74LS series gates and to an optical encoder, a cable to transfer data over RS232 to/from PC, an electric motor driven through the amplifier, 1mF capacitors decoupling the power from the batteries, ADC that read voltage and current on the motor etc.

ESD from my finger strikes the board. It doesn't break it at the point where it entered the board. It blows the microcontroller port where it exits.

Where? Think before reading further. Which of the mentioned components got utterly destroyed?


Here's the answer: Everything was a tabletop demonstration. Practically nothing was really grounded, the capacitors didn't mean a target "deep" enough, the ADC, DAC, motor outputs, inputs, all survived. It was the RS232 TX port pin, because the PC was grounded and it was the only route the current leaving my body could take.
Blown port, no way to reprogram the board, good bye.