ESD protection for max1044???

Started by 12afael, March 31, 2008, 07:04:09 PM

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12afael

I want to add some ESD protection to a voltage inverter using a max1044(or ltc1044, etc), someone have an idea of how I can do it? I `ve already burned one :icon_redface:
thanks

Rafael

flo

A zener diode in series with a 10 Ohm resistance should protect it against voltage spikes / over-voltage. Especially the LTC1044 can not take more than 9.5V.

Sir H C

ESD or overvoltage?  I think the Maxim parts have pretty damn good ESD protection, but not necessarily good overvoltage protection.  The zener is probably the best idea.

12afael

ESD is a kind of overvoltage isn`t? I`ve seen how a ESD meter show a voltage of 8000V in a chair where I was sitting(IIRC).

thanks for the zenerd idea.

soulsonic

The Klon Centaur uses a 1N4742 12v 1w Zener diode between the B+ and ground for ESD protection. This is no secret - that part isn't even under the goop, so you can clearly see it if you look closely.
You can see it here:


The MAX1044 (and its cousins) are CMOS devices and are therefore HIGHLY susceptible to ESD damage. I believe people are frying theirs just by changing the battery and touching the snap. Some kind of protection like a Zener is an absolute necessity.
And if all this damage people are getting is from over-voltage, why does the Centaur use a 12v Zener (without a voltage dropping series resistor!)? Has anyone ever heard of a Centaur being fried?
I believe ESD protection is the most important thing to consider when using a charge pump chip.
Check out my NEW DIY site - http://solgrind.wordpress.com

Sir H C

ESD is the idea that you have shuffled across the carpet, have built up a high voltage low power/current charge on you and that you touch the component.  Overvoltage assumes that you have a large amount of continuous current at hand for the overvoltage.  In general, where a chip can handle hundreds or thousands of volts in an ESD event, if you give it an overvoltage of only 20 percent or so, you can kill the chip.  

soulsonic

I mentioned that the MAX1044 is a CMOS device - that means than any ESD can easily kill it.
There is NO PROTECTION IN THE CHIP!!!
Without ESD protection, the chip is a sitting duck waiting to get fried.
People need to stop harping on over-voltage and start paying attention to the reality that ESD is killing people's chips because they aren't being careful enough with them. You have to have the proper protection included in the circuit design and you should be protected while handling them.
Check out my NEW DIY site - http://solgrind.wordpress.com