Thread: LED Strip Power
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Unread 23-02-2015, 13:06
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Re: LED Strip Power

Quote:
Originally Posted by Mike Bortfeldt View Post
I've used this successfully in the past.
Use this or one of the 12V to 5V Voltage Converters from previous years (check the output current capacity first).


Quote:
Originally Posted by wmarshall11 View Post
Would throwing a couple of 5v regulators in parallel work for your application? Something like 4 LM323's on a perf board (with appropriate filtering) should be enough for your application.

Edit: See below and apparently don't do this. Also I may have a soon-to-be-crispy board floating around and should actually learn to EE.
A single LM323 would be sufficient if you have a large enough heat sink. Putting multiple linear regulators in parallel will not give you more output current capacity than with just one. Increasing the output current capability of a linear voltage regulator is done by adding a large output device.


Quote:
Originally Posted by GeeTwo View Post
AAAAAAAAAAAAA!

Putting regulators in parallel is never a good idea unless you put enough resistance between each of the outputs to allow the variation in output voltage to go somewhere other than frying electronics.
The internal circuitry of all the linear regulators I have ever looked at are such that they can only source current and cannot sink current. Because of this, they cannot "fight" each other. The one that has the highest output voltage, by even a few millivolts, will end up supplying most or all of the output current. The other ones will sense the higher output voltage and shut off their output stage so that they supply little or no current to the load. In this mode of operation, they are not likely to be damaged.

The output isolating resistors will cause the output voltage to be lower than what you may want unless there is circuitry to compensate for them.