>> ..., sometimes the whole IC literally blows up. Sounds like the chip got into latch-up mode. This is caused by too much current on a pin (in this case ESD-spike), making part of the chip trigger like an SCR. It is probable that the chip in some cases should have survived the ESD-spike itself, if we just eliminated the high current. This might be done by putting a series resistor to the supply (The supply current is very low) and a zener and a small cap (10nF) on the chip side to stabilize and limit. If latchup occours it might reset itself if R is hight enough, else it resets at power off. Of course, use all ESD protection discussed here too /Morgan Morgan Olsson ph +46(0)414 70741 MORGANS REGLERTEKNIK fax +46(0)414 70331 H�LLEK�S (in A-Z letters: "HALLEKAS") SE-277 35 KIVIK, SWEDEN mrt@iname.com ___________________________________________________________