Voltage Regulator Question

Thread Starter

pcon2009

Joined Aug 5, 2012
18
This should be a fairly simple question for those in the know, but I am having difficulty getting a direct answer out of research.

With a voltage regulator IC, such as an L7815CV, I understand that the idea is for it to output 15V... Question is, with what input? Will it act as a boost converter if I apply, say 12V to the input, as well as reduce the voltage to 15V if 24v were supplied?

Hopefully someone can clarify this for me. Thanks!
 

fender7802

Joined Apr 7, 2012
43
Hello,

Voltage regulators require an input voltage greater than the specified output voltage. The difference between input voltage and output voltage is known as "dropout voltage". You most likely will have to apply about 17V or more to get the 15V output (2V minimum dropout voltage).

Hope this helps!
 

crutschow

Joined Mar 14, 2008
34,201
That is a linear regulator which can only regulate voltage below its input voltage. To boost the voltage you need a switching regulator.
 
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