Response to the following problem:
The variability (? ID/ID) in the bias current ID due to the variability (?Vt /Vt) in the threshold voltage Vt can be evaluated from
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and find the variability in ID for Vt =0.5 V and _Vt /Vt = ± 5%. Let the MOSFET be biased at VOV = 0.25 V.
For the case of a MOSFET biased with a fixed gate voltage VG and a resistance RS included in the source lead, show that
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For the same parameters given in (a), find the required value of (IDRS) and VG to limit ? ID/ID to ± 5%. What value of RS is needed if ID is 100 μA?