1. Design a dierential input dierential output op-amp with capacitive feedback as
shown in Fig. 1. Achieve the following specications while minimizing power consumption
Closed-loop gain 5 (absolute not dB)
Load Capacitance 2 pF
Settling time 40 nS for 0.01% settling
Supply Voltage 1.8 V
HD3 (Closed-loop) -50 dB
What is the HD2 and HD3 during open-loop and closed-loop operation?
Note: The only ideal supplies allowed in the design are (a) VDD = 1.8V or
lower, (b) One reference current source of 100 A.
Please report the following –
(a) Quantitative design approach and justication for device sizes and tradeos.
(b) Clear schematics with annotated DC voltages and bias currents through devices along
with the operating points such as VDS and VGS.
(c) Simulated AC performance in open loop, simulated AC performance in closed loop,
simulated common-mode to dierential-mode rejection ratio
(d) Transient sim with positive and negative step responses with settling time.
(e) Simulation of HD2 and HD3 using transients.
(f) Tar of your cadence library.