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PyPortal BOM question...
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PyPortal BOM question...

by microfoundry on Thu Jul 23, 2020 12:49 pm

I see the PyPortal boards have 3.6v zener diodes on the 2 I/O ports which I assume are for some level of ESD protection, correct? I'm building a data collection device to feed my PyPortal via i2c and will utilize the 2 I/O also. I like the ESD protection idea but have no clue as to what an appropriate zener diode would be. Anyone care to share some example of a manufacturer / part-number?

TIA,

-Terry

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Re: PyPortal BOM question...

by kattni on Thu Jul 23, 2020 1:18 pm

I looked into it. They are to protect from overvoltages. https://www.google.com/search?client=fi ... protection

Here is some information on their usage: https://components101.com/articles/desi ... ner-diodes

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Re: PyPortal BOM question...

by siddacious on Thu Jul 23, 2020 1:41 pm

The diodes in question are most likely to protect the main processor which is a 3.3v device. With this in mind, you'll want a zener that will breakdown at a bit higher than 3.3v to allow for some normal fluctuations, 3.6V is a decent number.

I found this useful:
https://www.digikey.com/en/maker/blogs/ ... plications

https://www.digikey.com/products/en/dis ... ageSize=25

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Re: PyPortal BOM question...

by microfoundry on Thu Jul 23, 2020 4:24 pm

Thank you for the info. I love you y'all do, keep up the great work!

-Terry

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Posts: 2
Joined: Sun May 03, 2020 7:40 pm

Please be positive and constructive with your questions and comments.