When to use ESD protected?

I need to have a several PIC16F783s talk to each other in pairs over about

40' in the boat. MAX232's come in several flavors. the -30C non-protected chips from TI cost about $1 and the protected Maxim version costs $5. For what I have spent on the boat so far $$45 is no big thing but I would like to know if it is really needed.

BTW, you guys goaded me into microcontrollers and after the original frustration I have found assembler is actually kinda fun. When you have spent 30 years trying to write idiot proof application software for imaginative idiots doing it for a silicon chip with no imagination is a joy. :-)

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack 
there of) at:  http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com
Reply to
Glenn Ashmore
Loading thread data ...

Well, it sounds like you are doing a one off control of some sort. Wouldn't it be best to use the ESD protected IC and not need it than to go cheap and find out you should have gotten the ESD part? BTW, you usually find these things out at the worse possible time.

Jim

Reply to
James Beck

Yes, think St Elmo's Fire.

--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk
Reply to
John Woodgate

If you have to ask, you can't afford it. ;-P

It doesn't matter if it's "needed." It's a boat, for heaven's sakes! What's 45 bucks in a boat?

And yes, imagine a lightning strike going down through your mast and every electronic bit in the boat on its way to the water.

Ayup. :-)

Cheers! Rich

Reply to
Rich Grise

___________ In terms of handling, I've handled thousands of CMOS parts with very little in the way of ESD precautions, and never lost one. Basically, just use common sense. Being wired to the bench becomes extremely irritating in the course of a long day. Occasionally a defective circuit will fry it, but that's something else. As for surviving in its application, on-chip Zeners or whatnot are not going to make any difference in a lightning strike or near-miss. The circuit external to the chips should provide all the protection that you think it should have.

Reply to
Palinurus

Always there are exceptions, but for the most part, ESD does not make a CMOS device instantly unusable, but it will do subtle amounts of internal damage that may not show up until long after the fact.

I will not argue with experts, but I have seen a lot of long term failures in products that are hard to explain, and would not be surprised to know that a number of them were due to ESD issues when the product was first built. Tough one to track.

I would pay the extra money for the protected parts, and not have to sit and wonder what happened if the devices fail down the road.

JB

Reply to
learning

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.