Yes, I know what Vtp/Vtn means. It specifies the minimum |Vgs| needed to turn the mosfet on. This is required to create the channel.NPN and PNP refers to the polarity of BJTs. MOSFETs are defined as N-channel or P-channel.
The circuit is in the linear region when both MOSFETs are conducting at the same time. So under what input voltage conditions is that true? Do you know what Vtp and Vtn means?
Thank you for the video. It was helpful.How would you defined the linear region? And without any calculation I would pick answer B.
http://forum.allaboutcircuits.com/threads/pmos-souce-drain-voltage.47763/#post-314871
Good question. But forget about that, I wrongly understood the question. They ask only about M1 transistor. And ask about the linear region (triode region). So in this case I choose A as a right answer.Thank you for the video. It was helpful.
Option C and D are ruled out. Because for PMOS to turn on Vin<4V.
Why did you prefer B to A?
Answer A might be correct if it was >1.875V but it says <1.875V.Good question. But forget about that, I wrongly understood the question. They ask only about M1 transistor. And ask about the linear region (triode region). So in this case I choose A as a right answer.
M1 is a P channel so for Vin<1.875V M1 will be in triode/linear region.Answer A might be correct if it was >1.875V but it says <1.875V.
Egg on my face. I was thinking of M2.M1 is a P channel so for Vin<1.875V M1 will be in triode/linear region.
Jony, I understand that A is correct answer among these. But what does the value of 1.875V signifies here? Why it is a boundary? Or is it to be solved by just looking at options?M1 is a P channel so for Vin<1.875V M1 will be in triode/linear region.
Thanks a lot Jony!! You have helped me a lot here.Well for Vin>1.875 the M1 transistor leaves the linear region and enters the saturation region.
So, M1 is in linear region and M2 is in saturation.
ID1 = ID2
Id1 = Kp*(Vgs - Vtp)*Vds - Vds^2/2
Id2= 0.5*Kn*(Vgs - Vtn)^2
Then
(Vin - Vdd - Vtp)*(Vout-Vdd) - (Vout - Vdd)^2/2 = 0.5*(Vin - Vtn)^2
And M1 leaves the linear region when Vds = (Vgs - Vtp) hence Vout - Vdd = Vin - Vdd - Vtp
then
Vout = Vin - Vt
And after we solve this for Vin I get 1.8333V
http://www.wolframalpha.com/input/?i=(X - 5 - (-1)) * (X - 1 - 5) - (X - 1 - 5)^2/2 = (X - 1)^2/2
But I made a error so this solution is not true.
http://oldeee.see.ed.ac.uk/private/ee3/med/rc/week5MOSFET.pdf
http://www.prenhall.com/howe3/microelectronics/pdf_folder/lectures/tth/lecture11.fm5.pdf
http://nptel.ac.in/courses/117101058/downloads/Lec-15.pdf
by Jake Hertz
by Aaron Carman
by Aaron Carman