Regulate Car Outlet To 12.0 Volts

kgrant

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I need to regulate my cig outlet to 12.0 Volts, max draw 3 amps. What's the best way to do this? I can't seem to find anything commercially available. Thanks
 

DIPSTIX

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Usually this topic is avoided. It is a gateway subject which leads to people installing aftermarket LEDs in their vehicles which of course is not DOT approved.
 

kgrant

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Ok, interesting. This isn't going in my car. It's going to power a cellphone amplifier at my cabin. The manufacturer requires 12.0 Volts. I think I'll just use a cig plug inverter and wall wart. I was looking for something more efficient.
 
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dgbrookman

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The Powerstream PST-DC2012 is a bit on the expensive side, but is rated at 4A current and 90% efficiency. The inverter and wall wart setup would probably work OK though. The wall wart would help clean up the power from the inverter.
 

Steve K

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Ok, interesting. This isn't going in my car. It's going to power a cellphone amplifier at my cabin. The manufacturer requires 12.0 Volts. I think I'll just use a cig plug inverter and wall wart. I was looking for something more efficient.

boy... I'd be very surprised if 12VDC isn't a nominal value instead of an absolute max value. You might try contacting the manufacturer and asking about this.
 

kgrant

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boy... I'd be very surprised if 12VDC isn't a nominal value instead of an absolute max value. You might try contacting the manufacturer and asking about this.

I did contact them and they stated anything over 12.0v may damage the amplifier. They don't offer a dc power option because of FCC regulations for this size of amplifier to keep people from using them in a vehicle.

I did find a dc power supply for a Microsoft Surface that is regulated to 12v, max 4a. I should be able to use it.
 

Steve K

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I did contact them and they stated anything over 12.0v may damage the amplifier. ....

Well, if that's what they say, then it's best to follow their directions. I'm still scratching my head to understand why an amp would be strictly limited to 12V. Most analog parts are rated to at least 15V or so.

Is your MS Surface power supply designed to run from a car battery? If not, then there are some DC to DC converters that should do the job (depending on how much power you need). For example, Digikey sells this....
https://www.digikey.com/product-detail/en/cui-inc/PYB30-Q24-S12-U/102-3263-ND/4477521
It's not inexpensive; $58. It might be cheaper than an inverter and an AC powered DC source, though.
 

Lynx_Arc

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Ok, interesting. This isn't going in my car. It's going to power a cellphone amplifier at my cabin. The manufacturer requires 12.0 Volts. I think I'll just use a cig plug inverter and wall wart. I was looking for something more efficient.
It depends on what type of battery you are using as a source. Car batteries are not a lot above 12vdc if not on a charging circuit they typically read about 12.6-13v and a resistor would probably suffice at such a low voltage differential and current load if it was higher voltage then a linear regulator would probably suffice. It isn't until you get a larger voltage difference that other inverter type circuitry would be profitable. Like others here I'm more inclined to think that "exactly 12v" claim is rather bogus as most electronics have an operating voltage range that is usually a few volts wide. If the cellphone amplifier has a 12v power supply I would measure the voltage output of it both with and without the amplifier operating.
 

kgrant

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I wasn't searching for the right thing, thanks for showing me they do make what I'm looking for!

The Microsoft surface power supply has a cig plug on it. And it's only 10$. I bet the power supplys in the links you guys provided would be more precise, but I'm not sure if I need that.

I was also surprised they said only 12v for the amplifier. If it didn't cost $900 I wouldn't be so worried about the voltage.
 

kgrant

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Measured the wall wart output at 12.22 vdc with no load.

I can't test the output under load right now because I don't have the antennas on hand so I can't put a load the amplifier. Manufacturer says not to power it without antennas hooked up.
 
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