This problem is very frustrating to me, because it should be a simple, systematic problem and I want to understand it. When I set up the KCL at the drain, it is very similar to, but not quite the same as, the solution provided in the NCEES book.
Here is what I get for my KCL equation:
0 = (Vout-Vin)/Rg + gmVin + (Vout-15)/Rd + Vout/Rl
And here is what is provided in the NCEES book:
0 = (Vout-Vin)/Rg + gmVin + Vout/Rd + Vout/Rl
So you see, the only difference between my KCL equation and the book's is that my equation includes the 15 V in the (Vout-15)/Rd term. The 15 V seems to disappear in the NCEES book. The NCEES solution doesn't explain how this equation was derived; it just presents it.
What am I missing? I'm sure it's some very basic, important assumption that I'm forgetting, but I have looked at this problem for a long time and I can't understand why the 15 V disappears. This is so frustrating, because I am so close. Somebody please, please help me, for my sanity's sake.
Thank you in advance.
Here is what I get for my KCL equation:
0 = (Vout-Vin)/Rg + gmVin + (Vout-15)/Rd + Vout/Rl
And here is what is provided in the NCEES book:
0 = (Vout-Vin)/Rg + gmVin + Vout/Rd + Vout/Rl
So you see, the only difference between my KCL equation and the book's is that my equation includes the 15 V in the (Vout-15)/Rd term. The 15 V seems to disappear in the NCEES book. The NCEES solution doesn't explain how this equation was derived; it just presents it.
What am I missing? I'm sure it's some very basic, important assumption that I'm forgetting, but I have looked at this problem for a long time and I can't understand why the 15 V disappears. This is so frustrating, because I am so close. Somebody please, please help me, for my sanity's sake.
Thank you in advance.