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BrianG · 03.06.2011, 11:56 AM

For electronics prototyping, I have a homemade breadboard setup with a modded PC power supply as the supply. I only use the 12v output of the supply, but to get adjustable voltages, I then use a LM317T with a large pass-transistor mounted on a large heatsink to get for ~1.5 to ~10v @ 10A.

You have a drop-out with any linear regulator, so make sure your supply is rated for at least 2v higher than any voltage you will want. To get around this, I use a switch that selects 12v (direct from the PS) or adjustable (from the regulator).

Also be aware that the use of a linear regulator with high differential voltages and high output current, while simple, can create a lot of heat. If I am drawing 10A @ 3v for something, the heat will be (12v-3v)*10A=90w.

The use of a CCBEC Pro would be perfect, except you can't quickly and easily adjust it; you have to hook it to a PC. It would be really nice if you could hook up a pot to it somehow to adjust it...

	(#5)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	03.06.2011, 11:56 AM For electronics prototyping, I have a homemade breadboard setup with a modded PC power supply as the supply. I only use the 12v output of the supply, but to get adjustable voltages, I then use a LM317T with a large pass-transistor mounted on a large heatsink to get for ~1.5 to ~10v @ 10A. You have a drop-out with any linear regulator, so make sure your supply is rated for at least 2v higher than any voltage you will want. To get around this, I use a switch that selects 12v (direct from the PS) or adjustable (from the regulator). Also be aware that the use of a linear regulator with high differential voltages and high output current, while simple, can create a lot of heat. If I am drawing 10A @ 3v for something, the heat will be (12v-3v)*10A=90w. The use of a CCBEC Pro would be perfect, except you can't quickly and easily adjust it; you have to hook it to a PC. It would be really nice if you could hook up a pot to it somehow to adjust it...