Or put a big wattage resistor to drop down the 12V before feeding into regulators.
Use a 7805SR from Murata. That's a switching regulator that fits in the same space as a 7805 linear regulator. Because it's a switching regulator, it wastes very little energy, and doesn't get hot.
http://www.murata-ps.com/data/meters/dms...
Another choice is to salvage the switching regulator from a USB adapter that plugs into the cigarette lighter in a car. Those are also high efficiency, low heat.
Use a heatsink. It doesn't have to be a fancy commercial one, it can be a chunk of aluminum or copper, or the metal case of whatever.
Or use a switch-mode circuit.
Try using a Sieglitz K500 - yes, you can still find them - with a a self-polarising parallax neutraliser field. The Z parameters can go off the scale sometimes, but hey, who cares ?
This turns me on! :D
I've got 12 volts DC power supply. This seems to dissipate too much heat when i connect it to a 7805 regulator.
What if I connected it to a 7809 regulator followed by a 7805 regulator?
That way the 7809 regulator would drop 3/7 of the power and the 7805 would drop the remaining 4/7 of the power!?
of course I could just use a big bulky heatsink on the 7805!
