Hello!

I'm at my wit's end trying to find a good solution for a simple problem... I need a regulator that accepts about 12 - 24V input and outputs 5V, and at least 2A of current.

I know I can get a linear regulator, but I have size constraints. The heatsink I'd need just won't fit. I'm thinking I could just use a switching regulator IC (step-down). I'm familiar with IC's that need an inductor, a cap, and a diode, but my friend said that there are some certain voltage step-down IC's that do not need any external components. Can anyone give me suggestions?... THANKS!!!

 

These are available on the internet for very little money.

Sometimes I make my own, but often it is not worth it.

Buyincoins has these (for instance).

Even a switcher needs cooling for 2 Amps.

 

It can be done. But for a small number of units. It is better to purchase of the shelf. Here is one example http://www.tracopower.com/products/tsr3.pdf

 

Upto 1.5A, OKI-78SR series regulators available at Digikey. These are almost drop-in switching regulator replacements for 78XX series.

 

Wow, thanks for the replies!!!

I think I'm going to go with the LM2596. I can't buy premade boards because the regulator has to be part of a bigger board.

Now a follow up question. I don't think I'll be going beyond 2A. So, if the LM2596-5.0 has 80% efficiency, and I'll be drawing 2A max, will it always dissipate 2.5W??? I calculated that like this:

output of 5V * 2A = 10W
efficiency 0.8 so, 10W/0.8 = 12.5W of input needed for 10W.
12.5W - 10W = 2.5W

My question is, do i still need a heatsink for that?...