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Pololu 12V Step-Up Voltage Regulator
Topic Started: Jan 9 2014, 09:23 PM (348 Views)
Shed Boy
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I got this in the mail today.
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Hoping this will allow me to only have to use one battery. My lights and FPV gear all need 12 volts and the Blizzard and the Thumper both run 7.4 volts. Lights and FPV gear don't draw much so I think this should do it. I'll tap in right at the switch so everything comes on at one switch.

These guys have a pretty nice variety of electronic do-hickies and gear boxes with motors. www.pololu.com/
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Itch
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What kind of amps does it put out at 12 Volts? You didn't want to run a 3S lipo for your lights and FPV?
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Shed Boy
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Itch
Jan 15 2014, 08:40 AM
What kind of amps does it put out at 12 Volts? You didn't want to run a 3S lipo for your lights and FPV?
The specs say 5 amps in...I'm guessing that means 5 amps out too. 2 amps would be plenty for what I need.

Yes, I need 3s power for my FPV gear and lights. I would rather not pack a separate 3s battery if I can boost the voltage. I would rather carry an extra 2s battery to power the rig longer.

Inversely...I guess I could have used a 3s and dropped the voltage down. But 3s battery packs cost more and are bigger.

I haven't tried this thing yet. I'll update this thread once I see if/how well it works.
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Itch
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Looks like it'll work for you, and you can get about 2.25 amps max out at 12V from a 7.4V source from the chart.

Just doing the math:

If you have a 7.4 volt source with a max of 5amp: Watts=Volts*Amps....7.4*5=37 Watts input MAX. You can only get 37 watts out, assuming 100% efficiency, which isn't possible at the moment, but we will assume it does for math purposes.

Output: 37 Watts= 12 Volts (what you are asking it to put out) * Amps (what we don't know). 37/12 = 3.083 Amps output at 12 volts. Looks like you will be getting around 85% efficiency, so .85 * 3.083 gets you 2.62 amps mathematically. This is very rough for calculations and doesn't take into considerations all the other loses and additional heat loss.

They do have this image, which is what I would go off of though, but the math above is good reference for any future finds that may not have efficiency charts.

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Shed Boy
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Thanks Itch, good info! Gee, 85% efficiency is pretty decent. I was worried that it might be an energy hog and not make it worth it to not carry 2 batteries, but this just might do it.
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