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Author Topic: 12V to 5V DC to DC converters  (Read 5271 times)

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Offline DaaniiTopic starter

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12V to 5V DC to DC converters
« on: February 05, 2011, 03:20:03 AM »
I need to convert 12V DC to 5V DC to run a BeagleBoard, a USB hub, and some other electronics from a car battery. Do I need something as expensive as this: http://www.powerstream.com/dda.htm?

I want relatively high efficiency. Probably need about 3A maximum current.

Offline rbtying

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Re: 12V to 5V DC to DC converters
« Reply #1 on: February 05, 2011, 09:41:56 AM »
That isn't all that expensive for being ready-to-use.

Try this? : http://www.pololu.com/catalog/product/2110 (It's half the price, but will require you to find some connectors)

Offline DaaniiTopic starter

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Re: 12V to 5V DC to DC converters
« Reply #2 on: February 05, 2011, 02:10:08 PM »

Try this? : http://www.pololu.com/catalog/product/2110 (It's half the price, but will require you to find some connectors)

Good suggestion, that's a better choice for me. Looks like it comes with a choice of connectors, too.

Offline momomo68

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Re: 12V to 5V DC to DC converters
« Reply #3 on: February 06, 2011, 02:09:44 PM »

Offline HDL_CinC_Dragon

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Re: 12V to 5V DC to DC converters
« Reply #4 on: February 07, 2011, 10:23:06 AM »
The Switching Regulator that momo posted would be perfect for what youre trying to do. I used a similar setup a year and a half ago trying to run a few small test circuits off a deep cycle 12v SLA battery (Basically a car battery... but slightly different...). If you want efficiency, switching regulators are definitely the way to go. You also dont have to worry about it over heating itself either because unlike typical VREGs (Such as the one that the $50 robot uses) which dissipate the excess voltage as heat, this one just cuts the voltage on and off with a cap to filter its own noise.
I found a decent switching regulator for around like 6 or 7 bucks on one of the more common supplier websites last year when I shopped around for one... I want to say I found it on Digi key. If memory serves correctly, It came as an ~9 pin IC that looked like a typical audio amp. I forget its electrical properties though.... ill try to find it again and send you a link
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Offline DaaniiTopic starter

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Re: 12V to 5V DC to DC converters
« Reply #5 on: February 07, 2011, 05:31:40 PM »
Thanks for the suggestions. I too am using a deep-discharge 12V car battery. So the switching regulator the two of you describe should work well.

 


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