Hey guys, Ive been struggling with this transistor problem and I can't seem to figure out the problem. I am suppose to find the state that the transistor is in, and no matter what I do, it seems like I'm getting the wrong answer. I start off by assuming saturation and making the left side into a thevenin equivalent. This causes the Vs = Vth = 2.92V, and the Rb = Rth = 12.078kOhm.
Also β=100
KVL(1):
2.92V - Vb - 0.6V - Ve = 0
->2.32 = (12.078kOhm)Ib + (1kOhm)Ie
->2.32 = (12.078kOhm)Ib + (1kOhm)(Ib + Ic)
->2.32 = (13.078kOhm)Ib + (1kOhm)Ic
KVL(2):
15V - Vc - 0.2V - Ve = 0
->14.8V = (3kOhm)Ic + (1kOhm)Ie
->14.8V = (3kOhm)Ic + (1kOhm)(Ic + Ib)
->14.8V = (4kOhm)Ic + (1kOhm)Ib
Now you do a system of equations with (1) and (2) and you get a negative number for Ib, which isn't possible. And I'm very confused with what the issue is.
I also tried assuming that it was foreward active, but when I do this, and find the relation between Vce and Vs, I notice that the Vth of 2.92 is large enough for the transistor to be in saturation. So I believe that it should be saturated, but the math isn't working out correctly. Please help me!
Thank you.
Also β=100
KVL(1):
2.92V - Vb - 0.6V - Ve = 0
->2.32 = (12.078kOhm)Ib + (1kOhm)Ie
->2.32 = (12.078kOhm)Ib + (1kOhm)(Ib + Ic)
->2.32 = (13.078kOhm)Ib + (1kOhm)Ic
KVL(2):
15V - Vc - 0.2V - Ve = 0
->14.8V = (3kOhm)Ic + (1kOhm)Ie
->14.8V = (3kOhm)Ic + (1kOhm)(Ic + Ib)
->14.8V = (4kOhm)Ic + (1kOhm)Ib
Now you do a system of equations with (1) and (2) and you get a negative number for Ib, which isn't possible. And I'm very confused with what the issue is.
I also tried assuming that it was foreward active, but when I do this, and find the relation between Vce and Vs, I notice that the Vth of 2.92 is large enough for the transistor to be in saturation. So I believe that it should be saturated, but the math isn't working out correctly. Please help me!
Thank you.
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