1 parameter index

Process SMIC0.18um
working voltage VDD = 2.5V
slew rate SR ≥ 20V/us
load capacitance C_L = 2 pF
3dB bandwidth $f_{3dB}$ ≥ 1MHz
DC Gain |Av| ≥ 40
Power Consumption P ≤ 0.5mW
Common Mode Voltage V_{ICMR} = [ 0.8V , 1.6V ]

2 calculation process

See the handwritten version for detailed process

3 simulation process

3.1 Build the schematic diagram according to the W/L calculated in 2

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3.2 Simulation results

3.2.1 dc simulation

1. Set the VCM and VB values calculated in 2.
Run the DC simulation to check the working status of the tube.

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2. At the beginning, I forgot to set the W/L of the tailpipe. Press 220/180 to run, the pipe works in the linear area, increase the VB to 1.5v until it is saturated, and find the problem after inspection, adjust the W/L of the pipe, and then set the VB to 0.59V, then it can work normally.

3. The adjustment of the static working point of the pipe has not been fully grasped, and the understanding of this area needs to be strengthened.

3.2.2 ac simulation

1. Add a small AC signal with an amplitude of 0.2V to the input,
set the output, click Run, and check the gain and phase

Figure↓testbench
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Figure ↓ The gain is 82.7
, which meets the requirements of the index and is greater than 40 times.
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Display the gain as dB.
Note here that because the input is mv, directly use the dB20 function to calculate the gain, and a negative value will appear,
20lg(0.0827V) = -21.64dB