When to use ESD protected?

[Glenn Ashmore]

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

 

[James Beck]

In article <l%n5e.269$Z73.67@lakeread04>, gashmore@cox.net says...

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.



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

 

[John Woodgate]

I read in sci.electronics.design that James Beck
<jim@reallykillersystems.com> wrote (in
<MPG.1cc061221fba680e989b27@news.west.earthlink.net&gt about 'When to use
ESD protected?', on Fri, 8 Apr 2005:

In article <l%n5e.269$Z73.67@lakeread04>, gashmore@cox.net says...
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.



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
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

 

[Rich Grise]

On Fri, 08 Apr 2005 00:45:07 -0400, Glenn Ashmore wrote:

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.

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.

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.

Ayup.

Cheers!
Rich

 

[Palinurus]

Glenn Ashmore wrote:

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.

___________

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.

 

In <115jpfam88bou99@corp.supernews.com>, on 04/10/05
at 09:53 PM, Palinurus <trinitite@ev1.net> said:

Glenn Ashmore wrote:
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.

___________
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.

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