MY QUESTION: Suppose you have two voltage regulators that both are configured to output 12 volts. If the first one has a voltage input of 25 volts and the second one has a voltage input of 15 volts, which one gets hotter? YOUR ANSWER:
Thanks, Bruce in Fresno (designing how power motor speed controller.)
My answer? Do your own damn homework. You aren't doing yourself any favors by trying to cheat. Even if someone does give you the answers, you will be unprepared to pass your finals and unprepared to get a job.
-- The other, better looking, Dreaded Libertarian
Suck it and see.... LITERALLY :)
The dissipated power is the voltage difference over the regulator times the current.
the one with the undersized heatsink.
The 15 volt one.
Me? I'm trying to cut down on the competition. ;)
I once had one overheat because it was clamped onto shiny bright aluminium box. The ones on black anodised aluminium of the same size were fine. A coat of paint cured it.
Regards, Martin Brown
Just do not use it in the sun.
Nah, homework questions are more specific and less practical. If you have to ask for details to answer the question, it's not a homework question.
Given equal heat sinks, the linear regulator will get hotter than the switching regulator.
What is your _real_ question?
Three terminal regulators like the 7805 & 7812 work by dumping the excess energy to heat. The lower the voltage dropped across one the cooler it will run. I used a 7805 1-amp regulator last week from a 12 volt source and discovered that anything over 250 ma was going to need a heat sink.
I w>MY QUESTION: Suppose you have two voltage regulators that both are
:MY QUESTION: Suppose you have two voltage regulators that both are :configured to output 12 volts. If the first one has a voltage input :of 25 volts and the second one has a voltage input of 15 volts, which :one gets hotter? :YOUR ANSWER: : : :Thanks, :Bruce in Fresno (designing how power motor speed controller.)
You didn't specify the load for each case. If you have no load on either one then they will both be the same temperature - cool.
First, answer two more questions: Each at what current? Each what circuit type / topology? I do not care to guess in the dark.
The one putting out 100 Amps, rather than 100 milliAmps.
The one that isn't a switcher.
The one not in a bath of liquid nitrogen.
++++++++++++As in, not nearly enough is specified in this question (or is it a homework problem you were supposed to pick holes in yourself?)
The one downwind.
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