backup cam voltage regulation

Printed From: the12volt.com
Forum Name: Mobile Video, GPS, and Navigation
Forum Discription: Mobile Video Head Units, DVD Players, LCD and TFT Monitors, Navigation, GPS, PS2, PS3, XBox, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=116161
Printed Date: May 14, 2025 at 2:50 AM

Topic: backup cam voltage regulation

Posted By: dustins2000
Subject: backup cam voltage regulation
Date Posted: September 07, 2009 at 1:15 PM

I have a 2008 Nissan Armada. Im going to install a backup cam. I know how to do everything, its not hard but I have 1 question.

I want to use a factory camera (to keep the stock look). The connector has 4 pins: 6V power, ground, video, and shield.

How do I turn the 12VDC into 6VDC without the magical box that Nissan uses? Also, what can I do for the sheild? Thanks!

Replies:

Posted By: dustins2000
Date Posted: September 07, 2009 at 1:38 PM

Also, do I even need to step it down to 6v. I know its the amperage that will hurt it, not the supply voltage. just a thought....

Posted By: Ween
Date Posted: September 08, 2009 at 10:06 AM

Hi,

Yes, you should reduce the voltage to the camera. A LM317 (voltage regulator IC) and a few external parts will give you the desired output voltage. The shield is the outer conductor of a coaxial cable.

Posted By: dustins2000
Date Posted: September 08, 2009 at 7:39 PM

So if I buy and RCA cable from radioshack there will be a wire to connect to the shield wire?

Posted By: dustins2000
Date Posted: September 08, 2009 at 7:48 PM

When I was looking into that I found the LM138 which is a 5A voltage regulator. Where would I buy one of those? I only see places that sell them in bulk.

Posted By: Ween
Date Posted: September 08, 2009 at 8:04 PM

I wouldn't worry about the need for the LM138, definitely overkill for your application. A LM317 with a small heatsink/ piece of aluminum will work fine. Most cameras don't draw much power, unless the are setup for night use..infrared LED's. You'll need to cut the end off the RCA cable and twist the strands..or get an inline female jack and attach wires to it.

Posted By: KPierson
Date Posted: September 08, 2009 at 8:33 PM

If you are looking to order a voltage regulator just order a 7806 (like this one https://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=497-1445-5-ND)

It's a little easier then setting up a 317 to work correctly. However, 317s are typically available locally so they may be a bit cheaper. Either one will do the job though.

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Kevin Pierson