Hi Can someone please help me with my homework for the attached circuit i need to find all the resistor values given the following Ic = 1ma Vre = 10%Vcc Hfe min = 110 R2 = 0.1hfeminRe Vrc= 1/2(Vcc - Ve) If someone could show the steps involved it would be much appreciated! Cheers!
1. Assume Ie = Ic and Hfe = Hfe min 2. Given Vre (= Ve) & Ie you can find Re 3. Given Ve and Vcc, you can find Vrc and hence Rc (knowing Ic) 4. Knowing Re gives you R2 - per question statement 5. Given Ve and assuming Vbe = 0.65 (say) then you can find Vb 6. Given Hfe and Ic you can find Ib 7. Given Vb and R2 you can find Ir2 8. Given Ir2 & Ib you can find Ir1 9. Given Vcc, Vb and Ir1 you can find Vr1 and hence R1
Thanks for your help TNK, i got the following values R1 = 14.9K R2 = 16.5K Rc = 12.85K Re = 1.5K I hope these are right!
Re and R2 look correct. Show how you got Rc and R1 and I or someone else will make a comment or suggestions. Hint: Did you use the relationship you were given to find Vrc - Vrc= 1/2(Vcc - Ve) ??? What current values did you get for Ib and Ir2?