7.24 For the amplifier in Fig. 7.10, let VDD = 2 V, RD = 15 kΩ, Vt = 0.5 V, = 0.4 mA/V2, W/L = 12.5, VGS = 0.7 V, and λ = 0.
(a) Find the dc current ID and the dc voltage VDS.
(b) Find gm.
(c) Find the voltage gain.
(d) If vgs = 0.015 sin ωt volts, find vds assuming that the small-signal approximation holds. What are the minimum and maximum values of vDS?
(e) Use Eq. (7.28) to determine the various components of iD. Using the identity , determine the second-harmonic distortion defined as the ratio of the component of iD of frequency 2ω to the component of iD of frequency ω, multiplied by 100.
(a) 0.1 mA, 0.5 V; (b) 1 mA/V; (c) −15 V/V; (d) −0.225 sin ωt, V, 0.275 V, 0.725 V; (e) 1.9%
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