Question.6
A hardware developer drives a BC547 from a 5V MCU GPIO to switch 50 mA through an LED. Use hFE(min) = 100, V_BE = 0.7 V, and a forced β of 10 for guaranteed saturation.
What value of base resistor RB is needed?
Select Answer
470 Ω
860 Ω
4.3 kΩ
8.6 kΩ
