Author Topic: Voltage regulator not regulating  (Read 1218 times)

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Offline Warhawk87Topic starter

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Voltage regulator not regulating
« on: September 27, 2010, 04:05:42 PM »
Hey everyone,

I apparently blew out the voltage regulator on my duemilanove board so I built an external one... Two 100uF capacitors on the input and out of a 7805 regulator... Unfortunatly I'm still getting 12 volts from my multimeter...

Offline galannthegreat

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Re: Voltage regulator not regulating
« Reply #1 on: September 27, 2010, 05:53:11 PM »
Show us how you have it wired in, maybe you may have did something wrong.
Kurt

Offline Warhawk87Topic starter

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Re: Voltage regulator not regulating
« Reply #2 on: September 27, 2010, 07:02:39 PM »
its positive battery terminal to capacitor to voltage regulator, middle pin goes to ground, other voltage regulator pin goes to other capacitor which goes to ground.  I dont know how to physicaly show it to you so thats the best I got...

Offline waltr

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Re: Voltage regulator not regulating
« Reply #3 on: September 27, 2010, 07:35:23 PM »
Sounds like you have the regulator input and output pins reversed.
Recheck the pin-out on the data sheet and note if the view is from the bottom or the top. This has gotten me a few times.

Offline knossos

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Re: Voltage regulator not regulating
« Reply #4 on: September 27, 2010, 07:37:24 PM »
Waltr beet me to it, hehe.  If that isnt your problem, can you take a picture and post it or sketch your schematic in paint or something?
"Never regret thy fall,
O Icarus of the fearless flight
For the greatest tragedy of them all
Is never to feel the burning light."
 
Oscar Wilde

Offline Warhawk87Topic starter

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Re: Voltage regulator not regulating
« Reply #5 on: September 27, 2010, 08:48:06 PM »
If I put it in the wrong way would that have busted it? Because I thought of that too and switched it around but I still got nothing

Offline galannthegreat

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Re: Voltage regulator not regulating
« Reply #6 on: September 28, 2010, 01:56:45 AM »
It could have, but most linear regulators a pretty resilient. But if so, it's a 50 cent part, so I wouldn't worry.
Kurt

 


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