0
\$\begingroup\$

I'm designing a system to drive 5 strips of RGB LEDs, it will draw around 25 amps, at 12 volts.

This system is only going to be used by me, and I have the suitable power supply coming in the mail.

In my design I had a Schottky diode from the DC jack to the power regulator to protect against reverse voltage. I'm currently pulling together my BOM and getting ready to order my PCB and the parts, and I can't find a Schottky diode with ratings for what I need. I'm mainly worried about accidentally frying my pre-release MKR 1000 Arduino board I got that I'm using for the project.

My question is, is it worth it to try to find a diode for reverse voltage protection?

This many be too broad or controversial but I wanted to see what you guys think, and if there is any kind of rule-of-thumb that I should be following

\$\endgroup\$
  • 1
    \$\begingroup\$ You might be better served using a MOSFET for reverse polarity protection. See: this and this. \$\endgroup\$ – helloworld922 Feb 20 '16 at 6:34
  • 1
    \$\begingroup\$ It all depends of how much you want to protect your stuff vs the probability of you screwing things up. I'd leave it off just for kicks so you can train your self to always remember to check the power. Once you blow things out a few times, you remember to always always double check your setup before you turn things on. \$\endgroup\$ – laptop2d Feb 20 '16 at 6:45
  • 1
    \$\begingroup\$ You can't find a Schottky rated for more than 25A? There are plenty (Digikey says there are more than 300). For example. \$\endgroup\$ – uint128_t Feb 20 '16 at 6:45
  • \$\begingroup\$ @uint128_t oh hmm, that's weird I was looking on digikey and it said 0, guess I should double check my search filters... \$\endgroup\$ – Keith M Feb 20 '16 at 6:47
1
\$\begingroup\$

I would definitely not choose to 'skip it' on reverse-polarity protection. Even if you expect to be the only one to ever use it, that doesn't guarantee against accidentally hooking up a replacement power supply wrong when the first one dies in a few years.

I didn't search for schottky in particular, just high amps & low volts, but I found this one for you (under 0.5V @ 10A) 3 of those with 0.01ohm >=1W series resistors should do a pretty good job of protecting your investment ;)

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.