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Topic: 3 volt regulator (Read 833 times) previous topic - next topic

majenko

What is your incoming voltage?  How much current will you be drawing?

Given enough incoming voltage headroom, and low enough current draw, you could very easily use an LM317T regulator.  It's far from perfect, but a handy one to have lying around (I have lots here) as they can be adjusted to create a wide range of output voltages with just 2 resistors and a couple of capacitors.  They can even be wired up in a constant current arrangement, which is useful for driving LEDs.
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dhenry

It is very easy to tell. The 1117 has emitter output, like 7805. Thus the high drop out.

A typical LDO has collector output, and has a drop out voltage of less than 0.5v - and many times much lower, because of its collector output toplogy.

dhenry

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They can even be wired up in a constant current arrangement,


Any voltage regulators can be wired to do that.

majenko


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They can even be wired up in a constant current arrangement,


Any voltage regulators can be wired to do that.


Yes, but these ones are commonly wired up like that, so there are plenty of resources and schematics on the web for the "user" to get.
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dhenry

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these ones are commonly wired up like that,


Which ones are "those ones"?

lm317 has an advantage in this application because of its low Vref - so lower losses on the current-setting resistor.

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