Paul_KD7HB:
What did you see on the data sheets that lead you to think there MOSFETS would not get hot?Paul
On the datasheet of the p-channel FQP27p06: R.JA = 62.5 degrees/Watt
RDSon = 0.07 ohm
Max junction temperature = 175 degrees
Current from powersupply = 4 Amp
So this is how i calculated that they shouldn't get hot: (175 degrees - 25 degrees)/62.5 degrees/Watt = 2.4
0.07 ohm 44 = 1.12
So 2.4 > 1.12 So i don't have to use a heatsink ? But the mosfets are getting so hot that i can't even touch it.
I don't know what i have to do or change with my circuit ?
thank you for your reply !