[Amps] New NXP BLF578XR 1200W LDMOS FET is "indestructible"

[Paul Decker]

Over the years I've heard many people say that adequately cooling a transistor is difficult because it is so small.  It's really difficult for me to wrap my brain around that statement though after playing with the 3cx400A7/3cx800A7 series tubes.  If one were to take the anode cooler off the tube, they would end up with a piece of ceramic about 1.4" in diameter and about .75" high.  This is on par with the size of these transistors.   It seems to me the dissipated power per area is roughly the same when looking at the devices minus their coolers.  What would be interesting is if a transistor manufacturer took a page from the tube world and integrated similar cooling.