How to make each stage of pipeline ADC behave similarly?

Hi guys,

I would like to know how to make each stage of pipeline behave similarily as close to each other as possible. I mean the multiplication factor of residue in each stage should be nearly same among all stage of pipeline. Its doesnt matter if there are large errors in each stage but the error factors like the comparator offset ,multplication factor should be nearly equal for each of the stage. How can one design such piepline in layout.

thanks

Re: Pipeline adc layout

Modeling a Powerbus with HFSS

Geometry and setup

Double-sided PCB:
Size: 125 mm × 100 mm × 1 mm
Top and bottom metal: PEC
Dielectric: FR4, εr = 4.5, dielectric loss tangent = 0.015
Solution type: Driven terminal
Excitation: Voltage source (1 V, 50 ohms)
Boundary: Radiation
Analysis Setup:

Solution Frequency: 1.15 GHz
Maximum Number of Passes: 50
Maximum Delta S: 0.001
Do Lambda Refinement: 0.2
Maximum Refinement Passes: 40%
Sweep:

Sweep type: Discrete
Frequency Setup: 5 MHz - 2 GHz, Step Size = 5 MHz
hfss_powerbus.zip

Simulation result

Simulation Time: 12 hrs
Number of passes completed: 7
Number of tetrahedra: 39325

Decisions the user must make that affect the accuracy of the result

Solution type: driven terminal
Location of absorbing boundary: cylinder, radius=150 mm, height=300 mm
Maximum delta S: default = 0.2, this model = 0.001
Do lambda refinement: default = 0.333, this model =0.1
Maximum refinement passes: default=20%, this model=30%

Comments

How do we select the solution type?

Two kinds of solution types were used in this model, driven modal and driven terminal. Choose the Driven Modal solution type when you want HFSS to calculate the modal-based S-parameters. The S-matrix solutions will be expressed in terms of the incident and reflected powers of waveguide modes. Choose the Driven Terminal solution type when you want HFSS to calculate the far-zone radiation.

How do we select the excitation type?

In HFSS, impedance matrix parameters are computed from the S-parameters and port impedances. Since Lumped ports compute S-parameters directly at the port, it is more efficient to use a lumped port when you want HFSS to calculate the input impedance. Assign a voltage source when you want to specify the voltage and direction of the electric field on a surface. In this model, the power bus is driven by a voltage source with 50 ohm in series resistor. To simulate the voltage source, an idea voltage source was assigned to a rectangle from the edge of the upper layer to the RLC boundary. The RCL boundary is modeled as a 50 ohm resistor which is in series with the idea voltage source.

Screen shots


Fig. 1. Simulation model


Fig. 2. Simulation meshes


Fig. 3. Input impedance


Fig. 4. Electric field at 3 m, θ=0°, φ=0°


Fig. 5. Electric field at 3 m, θ=90°, φ=0°


Fig. 6. Electric field at 3 m, θ=90°, φ=90°