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my question is, I need to drop the voltage down from a car battery, probably 14v or 12v, down to 5v to power a picaxe microntroller. Would a voltage regulator work fine for this? which one would work best? Would that develope too much heat?

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closed as not a real question by Camil Staps, Nick Alexeev, clabacchio May 16 '13 at 7:28

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.

Current requirements? – Brian Carlton Feb 27 '13 at 0:47
Not nearly enough information. – NickHalden Feb 27 '13 at 1:10
Yes you can use a voltage regulator for this. What kind (to avoid producing too much heat) depends on how much current your Picaxe uses. – The Photon Feb 27 '13 at 1:12
According to picaxe.com/docs/picaxe_manual1.pdf "Power Supply: 4.5V or 5V DC is recommended. Do not use 6V, 7.2V or 9V battery packs, these could permanently damage the chip. For trouble-shooting use 3xAA cells only. 28X2/40X2 parts were also optionally available in special low power (1.8V to 3.3V) variants called the 28X2-3V and 40X2-3V. Note that 4.5V or 5V will permanently damage these special low power parts." – Gary S. Weaver Feb 27 '13 at 20:40
So, should be ~1 A ? (very roughly, depending on type and how much is left in battery) according to powerstream.com/AA-tests.htm and batteryuniversity.com/learn/article/… – Gary S. Weaver Feb 27 '13 at 20:40

Get a USB car charger. Those make 5 V efficiently and are designed to deal with the nasty parts of car power. Due to the high volume these things are produced in, you'll have a hard time making something as effective and cheap. At the very least they will put out 500 mA, but a "charger" will usually put out significantly more. 1 A or more output current is common. You left out the all-impotant information as to how much current you need, but 1 A is most likely well more than what a "pixace" needs.

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yeah you will be able to find a 2+ amp 5V regulator without too much problem... if you are sourcing online check to make sure the package is what you expect it to be (I am a dumb beginner and have been surprised a few times by tiny smd versions of what I am used to).

linear or switching will work fine for you, linear uses fewer pins, switching will probably run cooler.

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I would guess a 500mA version would work for you, but for a 1 off, it is often easier to just go big – Grady Player Feb 27 '13 at 2:13

Just use a voltage regulator from radio shack that's for 5 volts, I know they are overpriced but it's OK because you are only getting one component so it will be fine. If it burns out, get a more powerful one. Because I don't know your current requirements I don't think a microcontroller takes too much current so an amp should be plenty, just if it gets too hot get a more POWERFUL one.

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or add multiple in parallel (linear regulators only) – hassan789 Feb 27 '13 at 1:56

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