# Do we have a voltage drop across this ideal current source?

Additional info includes Vss=0V, Vdd=3V. Also assume saturation (since we have Vd=Vg) and λn=0. We also know the reference current but not the Resistor. I know Vgs and thus Vds but I am looking to find Vs/Vd/Vg. I am guessing that there is a voltage drop across the current source so it is not as straightforward as Vd=Vdd=Vg.

Can we calculate those voltages?

• Homework? What have you accomplished so far? – PDuarte Jun 2 '18 at 14:59
• Not homework, studying for exams. Proved strong inversion and saturation, determined Ir current and found Vgs from square law. – Kiotis Jun 2 '18 at 15:11
• Do you know Ib? – The Photon Jun 2 '18 at 15:27
• Yes, it is 100μA and I am also aware that it is equivalent to Ids. – Kiotis Jun 2 '18 at 15:30
• You have Vs.... – PDuarte Jun 2 '18 at 15:36

Do we have a voltage drop across this ideal current source?

Yes, an ideal current source will produce whatever voltage drop is necessary to maintain its defined output current.