>I interfaced the recommended way and it worked for a while ker-pow the >DSP's osc died and so did the DSP. I was just wondering if anybody has >experienced similiar occurances. I'm attributing this to static for I can't >find anything wrong with my design or construction. Though I can't finger >out how it got sparked in circuit ? Having a static sensitive component in circuit is NO guarantee at all that it is any safer than out of circuit - it is a dangerous illusion ! In fact depending on how you approach a circuit (that is; what you are wearing, level of humidity and how fast you move etc), it can be more susceptible because one side of the circuit might be very close to or at ground potential - here you come with a nice 1000V (or more) charge from walking across the carpet and pick up the board or attach a test clip. You will likely not feel a thing but nature will find a nice easy path for that stored charge - whereas if your board is already sitting (unplugged) on a more or less insulating surface then (even with that charge on your body) the board may not have a discharge path develop from you to ground so the board (or chip) can be a bit safer unplugged. So the answer is - ALWAYS use static protection - at least with wrist straps, even on BIPOLAR devices - since die sizes are getting smaller and they are now about as susceptible as cmos devices. And use a proper bench top, 3M is generally considered the best - since they also have an embedded nickel mesh under slightly conductive vinyl (so its OK for 110/240v type work). Oh and if you're the sort of guy who says you never have a static problem and nothing goes wrong - then IMHO you are just lucky (or your environment does not let too many charges hang around) and you end up playing the odds or you are now so embarrased at the realisation as to why things are starting to fail - and you're suffering from a bad case of denial ! There used to be a company here called 'AutoArc' that made welders using high power MOSFET's - by the time they realised and ended up getting the MOSFETs in sealed drums by the 100,000 - it was too late. Its a bit like a seat belt - you might drive around for years and never have a smash - but one day - BLAM and boy can it cost heaps ! I had lots of odd failures disappear dramatically after I used proper static protection devices about 15 years ago, if I get a call at 7pm on a Sunday night - I don't shiver in my legal boots anymore. The interesting and disturbing thing about electrostatic damage and various hints are:- 1. It need not be catastrophic - sometimes results in specs being shifted or rise times changing, usually slower (but sometimes it blows part of a capacitive driver and the rise time is faster, quite weird because ringing starts to appear etc). 2. Non catastrophic damage now, can result in device failure anytime from then on - due to electron migration stress. Funnily enough there is some correlation when the humidty changes - EITHER way ! 3. You very often don't feel a thing and your hair doesn't have to stand up either - if you have any that is (or use brylcream) ? 4. Even moving your hand through the air (above a static bench) can generate about 200v on your (hairy) arm. Go and touch a MOSFET (with no protection diodes) and its zapped (even on the bench and even whilst you are strapped in on wrist or ankle), so don't wave at someone through the window whilst soldering MOSFETs - or improve the static controls using one of those air static field dissipators by 3M etc. 5. Putting some fluorescent lights above a normal static control mat can induce enough voltage to damage MOSFETS. This happened to me and was fully reproducable, we found about 27volts of 50Hz as potential difference between the wrist strap and ground connection of the mat - only when the fluorescents were on. Since the MOSFETs gate impedance is several hundred ohms it was easy to see that the gates were susceptible to puncture, we blew about 20% of them quite consistently. The potential difference of 27-30v was measured on a 10Meg voltmeter. The cure was to move the fluoro AND reduce the mats bleed resistor from 1Meg to about 200K, anything less than about 100K allows to fast a bleed and can cause just as much damage as if you never had a static mat or strap. 6. Putting a fully grounded metal surface underneath any boards can make matters far worse - especially if you are doing any work on mains equipment. Even putting a resistor between (aluminium) sheet and ground doesn't help that much. Thats the whole point about static mats the top seurface is a quite good insulator with a ghood charge bleed from the conductive layer underneath. 7. Using sticky tape to fasten the end of tubes holding integrated circuits may subject them to damage - even on static control mats. 8. Pushing integrated circuits into polystyrene covered with aluminium foil (you TV service guys) does not protect at all well - since momentary gaps between the pins and the foil allows a mechanism for static to hit that pin... 9. Holding unprotected parts clasped in a closed hand just puts your sweat (from the stress of picking it up?) onto the part so its going to be harder to solder and the pins get bent, so when you use your nice plastic grip-pliers to straighten the pins - guess what happens... 10. There is *NO* definitive way (unless you open the device under a ** microscope) to be sure static damage has not already occured to ** a board or component - even if it seems to *'work'* !!! So thats it chaps if you run any sort of professional outfit its absolutely necessary to have good static protection. Just think about it next time you are up in one of those fly-by-wire airplanes and you hope the manufacturer AND field service engineers use GOOD and proper static handling procedures AT ALL TIMES on any of those [buggy] flight control systems - especially where the designer has the lack of foresight to remove the pilot from the feedback loop with those dumb joysticks ! I suppose thats one reason why the older jets (and cars) can be a bit more desirable sometimes... Hewlett Packard made a major study of all sorts of electrostatic effects about 15 to 20 years ago (and as a result saved about *$100Million* ) - anybody know if the reports are on an ftp site, I can't find them ? Rgds Mike Perth, Western Australia (The most isolated city on the driest continent on Earth). PS: I have no affiliation with 3M or any static control companies, I'm just a guy that wants to arrive safely after a flight AND hopes like hell the aircraft is not a fly-by-wire (with S/W bugs) AND hopes like more hell that budding control systems designers, manufacturers and field service engineers ALWAYS use static protection - since my life and yours and our childrens really does depend and RELY on it ...... ! Some say there is no magic but, all things begin with thought then it becomes academic, then some poor slob works out a practical way to implement all that theory, this is called Engineering - for most people another form of magic. Massen