kdg007
Full Member level 3
I have built a simple circuit .I needed Ic = 23ma.. i have calculated and kept the resistor values for the requirement.Please give me suggestions if i have done any thing wrong ??? thank you
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Calculation :
1)Rc = (Vcc-Vce-Vled)/Ib = (5-0.06-3.5) / 23mA = 62 (kept 75 ohms as nearest value )
2) Ic = 19mA => Ib = 23mA/10 = 2.3mA
3)Rb=(Vin-Vbe) / Ib = (5-0.8) / 2.3mA = 1.8kOhms (took 1.5kohms as nearest value)
4)Iceo = 0.1microamp => so, i have to choose R3 such that it should drop 0.1microamp at the worst case. after trying few values i got 4.7k as good choice.... 4.7k drops 0.16microamps.