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Re: truck battery to 12vdc regulated supply

Posted: Tue Sep 13, 2005 7:55 pm
by positronicle
--Edited by Positronicle--

Re: truck battery to 12vdc regulated supply

Posted: Tue Sep 13, 2005 9:57 pm
by terri
Where are you driving this rig with all that entertainment stuff?<p>I want to know so I can avoid the roads in that part of the country.<p>[ September 13, 2005: Message edited by: terri ]</p>

Re: truck battery to 12vdc regulated supply

Posted: Tue Sep 13, 2005 10:19 pm
by High4Volts
Terri- Colorado mainly.... ;) It's legal as long as the driver can not see the screen. I don't plan to use the GPS unless i'm on a long trips which i will have my girlfriend with me so i can make her drive so i can pla... errrr i mean moniter the gps and other things on there.. *grin*

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 8:57 am
by terri
Yikes!<p>Who answers the cell phone?

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 3:06 pm
by High4Volts
Terri.. that's what speaker phone is for.. leaves one hand free to adjust the radio station and the other to surf to www.nutsvolts.com ;)
Seriously, if anyone has a simple diagram useing the nte970 as positronicle suggested that would be so awesome. I did a few web searches but all i come up with are PSU's others want you to buy..

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 4:53 pm
by Robert Reed
Without the bother of googling, just what are these NTE devices any how? A low dropout regulator? 12VDC regulated is getting might close to input voltage available.

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 5:08 pm
by Chris Smith
Industry Number : NTE970
NTE Device Number: NTE970
IC-POS VR,1.2-33V,3A,TO-3

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 5:20 pm
by jollyrgr
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by positronicle:
<p>How does the regulator block voltage between the battery and an this device?<hr></blockquote><p>Typically 3 Terminal regulators have a bipolar pass transistor. This transistor is switched on and off to regulate the voltage. Thus voltage can flow from the input terminal to the output terminal easily. But if there is a cap on the output of the regulator and the input is suddenly disconnected from power (but there are other loads in parallel with the regulator input) power from the capacitor on the output won't flow backwards from the capacitor to the regulator input.<p>But I did notice something that was posted about this screen; it needs 2 amps. The NTE956 can handle a max of 1.5 amps. So this regulator won't cut it without some sort of power transistor arrangement.<p>Another idea. 12V to 120V inverter. The original power supply plugged into the output of the inverter.<p>Or how about building a regulator from a 2N3055 (or similar transistor) and make a high current linear regulator. <p>Here is an example of one done using a zener diode.<p>http://www.mp3car.com/vbulletin/showthread.php?t=17905<p>The same thing can be done by attaching the base of the transistor to the output of the regulator. Throw a resistor on the output of the regulator as well to act as a load.<p>Take note: If the "thunder capacitor" is the far right cap in the referenced schematic, the power stored in the cap cannot go backwards through the transistor and is thus isolated from the battery source.

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 6:25 pm
by positronicle
--Edited by Positronicle--

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 7:19 pm
by High4Volts
Jolly, that's kinda what i am looking for. I would like it to still produce 12vdc while under a cranking load. Kinda what this picture is showing on that website Here! Is this simulation correct or as they talk in the message board, saying it will not work?

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 7:47 pm
by Chris Smith
Small Battery followed by a regulator.

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 8:32 pm
by High4Volts
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by Chris Smith:
Small Battery followed by a regulator.<hr></blockquote><p>What type of regulator would you use Chris?

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 8:42 pm
by positronicle
--Edited by Positronicle--

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 8:54 pm
by High4Volts
so the 2 amps is going to pull it way down. Think a 26000 microF would do?

Re: truck battery to 12vdc regulated supply

Posted: Wed Sep 14, 2005 8:54 pm
by positronicle
--Edited by Positronicle--