Prompt B — Historical & conceptual reflection: Discuss how the transition from analog to digital signal processing changed circuit design priorities in power, bandwidth, and noise, citing specific examples (filters, amplifiers, communications receivers). Include one prediction for the next major shift in EE design over the next decade.
Problem 5 — Op-amp design (15 pts) Design an inverting amplifier with gain -10 using a real op-amp whose open-loop gain Aol(s) ≈ 10^5/(1 + s/2π·10 Hz). a) (6 pts) Choose Rf and Rin values (standard decade resistances) to realize the closed-loop midband gain -10 and justify choice. b) (5 pts) Compute the closed-loop bandwidth approximately using op-amp open-loop dominant pole. c) (4 pts) Discuss one stability concern with using very large feedback capacitances in the feedback network.
Problem 6 — Three-phase & power (12 pts) A balanced Y-connected load: Z_phase = 10∠30° Ω, supplied by a 208 V (line) three-phase system. a) (6 pts) Find phase and line currents (phasors) and per-phase real, reactive, and apparent power. b) (6 pts) If one phase goes open (unbalanced), describe qualitatively what happens to neutral current and load voltages.
Prompt A — Innovation case: Propose a compact, low-cost power-supply module for a battery-powered sensor node requiring 3.3 V at 100 mA from a 3.7 V Li-ion cell. Include topology choice, efficiency considerations, thermal constraints, component selection rationale, and brief EMI mitigation strategies.
