Calculate the input current Iin for which the Darlington transistor D will begin to turn ON, and estimate a minimum value of Iin which guarantees that D will saturate. (here, the saturation voltage can be ignored; you may assume that in saturation VC = 0)
My attempt:
Iin = Vin / R
= 1.2 / 1000
= 0.0012mA
Ic = 15 / 15
= 1mA
Iin (sat) : Iin = Ic / 1000
= 1 / 1000
= 0.001mA
This was my final answer and I was right up to here, but the answer for Iin (sat) was actually 2.2μA. I dont get why Iin (sat) is the sum of the 2 Iin s that were worked out.
My attempt:
Iin = Vin / R
= 1.2 / 1000
= 0.0012mA
Ic = 15 / 15
= 1mA
Iin (sat) : Iin = Ic / 1000
= 1 / 1000
= 0.001mA
This was my final answer and I was right up to here, but the answer for Iin (sat) was actually 2.2μA. I dont get why Iin (sat) is the sum of the 2 Iin s that were worked out.
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