Dummy load - 4 NMOS share the load

MOSFET do have a positive temperatur coefficient and dont need source resistors. Could you explain why you think its nessesary?

I also though so. But after reading the reply#6 to the tread cited on the forum descripion, I understand that the +temp.co. when driven hard. I'll try to edit the description so the link points to reply #6

"The thermal-runaway situation occurs when you use large devices at low current-limit settings.” Thermal Stability of MOSFETs, ON semi AND8199/D, http ://www.onsemi.com/pub_link/Collateral/AND8199-D.PDF

The link did not worked for me, now its better lets see....

Ok i heard about that, and this reads like a joke, but makes sense. What I'm missing in this appnote and8199-d.pdf is how this effect is explained by physics. I think MOSFET have negative as BJT, but because of thier internal wiring structur (thousends of fets interconected by metal layer in parallel) its the wiring dominating by high currents. For lower currents it turns around and fets behaviour like normal BJTs and have a termal runaway. This is only a problem if you use for switching optimized mosfets and use them for linear application. I hate MOSFET for linear applications. Just take biplor and forget all this fucking driver controller for mosfets ;-) BTW, there are special MOSFETs for linear operation which do not have this coeff turnaround and selfdestruction! Thanx to highlight this!