# Simple MOSFET current mirror, Cascode Current Mirror, Impedance and Output Voltage Swing

Sorry if I don't format this exactly correct, this is my first post on this site.

I am working with a simple MOSFET current mirror and a cascode current mirror and need to determine the output swing and impedance of each. In a DC sweep of Vo from 0 to 5V, I graphed $$\ID2\$$ and $$\\large\frac{1}{D(ID2)}\$$ versus $$\Vo\$$ while $$\Vo\$$ and ended up with the following results for each respective circuit. I believe that the $$\\large\frac{1}{D(ID2)}\$$ plot represents the impedance but am unsure. As far as the Voltage output swing from what I have found online the minimum output voltage that can be used for the simple current mirror to operate is Vomin=VGS. For the Cascode current mirror I am also very unsure but believe it to be $$\Vomin= 2Vgs + Vt\$$. From what I understand there would be no maximum voltage output limit which makes me think that I may be calculating the completely wrong swing in general. Any help would be greatly appreciated and once again sorry for the format I promise I will improve lol simulate this circuit – Schematic created using CircuitLab simulate this circuit  • Welcome to the site. This sounds like a homework question. They are not typically answered without a bit more background and research. You will get better replies if you can boil down your message to a set of concrete questions, as well as what you have tried to do on your own... – spuck Nov 11 '20 at 22:47