QuoteP=IV = 6W, heatsink recommended I think!Yes, I agree with that. Same time it's applicable to any BJT, Darlingtons just have saturation little bit higher than others. So the trade is TIP120 + heatsink or MOSFET + TC426.
P=IV = 6W, heatsink recommended I think!
You only need a mosfet driver if you are switching much larger currents than the TIP120 can handle, or are using fast PWM
Darlington TIP127 has no trouble with voltage as low, as 2V at the base.
Actually 2.5V max @ Ic=3A according to the datasheet. If I was only switching 3A, I would probably use one of these http://www.farnell.com/datasheets/1648222.pdf which only needs 1.8V.
I was referring to P-channel , when I need high side switch in low voltage (< 3.3V) design.
I wish I had equipment to solder SMD components