Note:
(1) Please use A4 size papers.
(2) Please use the SPICE model on page 3 for simulation and calculation.
1. [MOSFET DC Biasing, 60%] Use the drain current equations below. Donβt consider channel-length modulation and body effect. Assuming Wdrawn /Ldrawn =20ΞΌm/2ΞΌm,sketchIX ofM1 asafunctionofVX increasing from 0 V to VDD = 5 V. (Note: finish this part before the midterm exam)
π π π π
= ΞΌ π π [(π β π )π β π π π] (NMOS in triode region) π π§π¨π±ππππ πππππππππ
= π ΞΌ π π (π β π )π (NMOS in saturation region) π ππ§π¨π±ππππ ππ ππ
= ΞΌ π π [(π β |π |)π β π π π] (PMOS in triode region) π π©π¨π±ππππ ππ ππ πππππ
= π ΞΌ π π (π β |π |)π (PMOS in saturation region) π ππ©π¨π±ππππ ππ ππ
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2. [MOSFET Small-Signal Model] Assume Wdrawn / Ldrawn = 20 ΞΌm / 2 ΞΌm. (a) [20%] Use Pspice to plot the drain current of a NMOS as a function ofVDS increasingfrom0Vto5V,atVGS =1V,1.5Vand2V.Label the off, triode and saturation regions for each curve. Derive ro from each curve in the saturation region and compare it with hand-calculation result. (b) [20%] Use Pspice to plot the drain current of a NMOS as a function ofVGS increasingfrom0Vto3V,atVDS =5V.Derivegmfromthe curve when VGS = 2 V and compare it with hand-calculation result.
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Vacuum permittivity (ππ¨) = π. ππ Γ ππβππ (F / m) Silicon oxide dielectric constant (ππ«) = π. π
