Use 12v fans for your ESC/motor...

oh yeah, Brian, sweet regulator and write up man. thx

[BrianG]

Actually, if I really wanted to get anal about it, I would have written this:

In a linear regulator, no matter what the output voltage is, the current required by the load will be the same as the current from the battery. So, 1A at 12v will be 1A from the battery whether it's 15v or 200v. This is why they are so inefficient.

In a switching regulator, it's a power transfer. 1A at 5v UBEC output would be only 0.29A at 20v (assuming switching efficiency of ~85%).

:)

[Dafni]

Most fans I use are 5V, running them off the UBEC's 6V.
Sometimes I use 12V directly on the main batts. They seem to survive even on 5S setups :026: No doubt they are suffering, but if one goes, it just get's replaced. Usually they last pretty long, though. Can't remember when I killed my last fan.

[BrianG]

@AAngel: The insulator is used because the metal tab on many regulators is electrically the same point as the output of the IC. So, if you don't use it, the heatsink (and the shole chassis if you use the chassis as a heatsink) will be floating at 12v.

The pad I used is some kind of mica part that is electrically insulative, but thermally conductive. It's not really an ideal thermal conductor, but given the heat levels for this "circuit", it is more than adequate. I'd rather trade off a tad bit of thermal performance for the electrical insulative properties, especially since we dealing with power losses on the order of less than 1w.

@Dafni: I'm sure most fans have a working range. I just get real anal about running them (and anything really) higher than rated.