So, I am working on a project where I am running about a 300mA load through a transistor. I have tried two different transistors, one rated at 500mA(2N-4401-218), and the other rated at 1A(C1384-031). They both burn up, and I am wondering if I have misunderstood the Amp ratings, or if I just need to heat-sink these somehow. ? ? ?

Here is the schematic: The 18 ohm and 15 ohm loads represent incandescent lights. They tend to be pulling about 300mA each

I also checked my power dissipation, the 2N4401 is rated at 630mW I checked my power dissipation and calculated it to be 301mW, (Vce*Ice+Vbe*Ibe) = (1.170*0.780+0.256*0.00126) = 301mW.

Here is the schematic: The 18 ohm and 15 ohm loads represent incandescent lights. They tend to be pulling about 300mA each

I also checked my power dissipation, the 2N4401 is rated at 630mW I checked my power dissipation and calculated it to be 301mW, (Vce*Ice+Vbe*Ibe) = (1.170*0.780+0.256*0.00126) = 301mW.

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