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Prefered: Undervolt or Overvolt a circuit?

sharpbiohazard

Sep 12, 2012
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Sep 12, 2012
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I have just finished building a color organ circuit from canakit.com http://www.canakit.com/3-channel-ac-colour-organ-kit-ck185-uk185.html

The kit calls for a regulated 12v DC supply in order to power the functions on the board. I have found an unregulated 12v@200mA DC supply and have built the common LM317 voltage regulator circuit to keep it under control. The kit pulls around 100mA while operating.

My problem is-

I cannot get an exact 12v value out of the voltage regulator, based on the restrictions of common value resistors. I can either choose to go 11.8v, or 12.4 volts.

My question is-

What is better for the circuit? Provide it with a little more voltage, or a little less?
 
Last edited:

john monks

Mar 9, 2012
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I would pick 11.8 volts.
If I am looking at the right part of the spec it says that a 9 volt source or a 12 volt source can be used.
 

BobK

Jan 5, 2010
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You are also not likely to get more than 10V from an LM317 with input of 12V.

Bob
 

BobK

Jan 5, 2010
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Okay, you might get by then with a current draw well below the rating of the power supply.

Bob
 
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