An NMOS technology has μnCox = 50 μA/V2 and Vt = 0.7 V. For a transistor with L = 1μm, find the value of W that results in gm 1mA/V at ID = 0.5 mA.
Consider an NMOS transistor having kn= 2 mA/V2. Let the transistor be biased at VOV = 1V. For operation in saturation, what dc bias current ID results? If a +0.1-V signal is superimposed on VGS, find the corresponding increment in collector current by evaluating the total collector current ID and subtracting the dc bias current ID.
We know ID =1/2 kn (VGS + vgs – Vt)2. Let the signal vgs be a sine wave with amplitude Vgs, and substitute vgs = Vgs sin ω t in Eq.(5.43). Using the trigonometric identity show that the ratio of the signal at frequency 2ω to that at frequency ω , expressed as a percentage (known as the second-harmonic distortion) is
If in a particular application Vgs is 10 mV, find the minimum overdrive voltage at which the transistor should be operated so that the second-harmonic distortion is kept to less than 1%.
(Q.5-Q.7) An NMOS amplifier is to be designed to provide a 0.50-V peak output signal across a 50-kΩ load that can be used as a drain resistor.
If a gain of at least 5 V/V is needed, what value of gm is required?
gmRd = 5 or gm= 5/50 mA/V.
Using a dc supply of 3 V, what values of ID and VOV would you choose?
What W/L ratio is required if μnCox = 200 μA/V2?
(Q.8-Q.9) For a 0.8-μm CMOS fabrication process: Vtn= 0.8 V, Vtp = −0.9 V, μnCox = 90 μA/V2, μpCox = 30 μA/V2, Cox = 1.9 fF/μm2, VA (n-channel devices) = 8L (μm), and |VA| (p-channel devices) = 12L (μm).
Q. Find the small-signal model parameters (gm, ro and gmb) for an NMOS transistor having W/L = 20 μm/2 μm and operating at ID = 100 μA and |VSB| = 1V.
Find the small-signal model parameters (gm, ro and gmb) for a PMOS transistor having W/L = 20 μm/2 μm and operating at ID = 100 μA and |VSB| = 1V.
The overdrive voltage at which each device must be operating is