EE 791D Data Converter Design 2 Introduction

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Data Converters

Signal Conditioning -Amplification -Anti-aliasing filter ADC MCU DAC Post Processing ex. Smoothing filter • Analog-to-Digital Converters (ADCs) provide an interface from the outside world to a computing system • Digital-to-Analog Converters (DACs) provide an interface from a computing system to the outside world 2

Why This Course on Data Converters?

• • • • • • Needed to interface with the physical world Data converters are everywhere – huge market Demand for increasing data converter performance keeps growing System-on-a-chip applications mean that data converters are in truly mixed-signal applications Data converters are typically the bleeding edge of analog/mixed-signal design Data converters are notoriously difficult to design 3

Why is data converter design difficult?

• • • • • Need high precision from imprecise parts Very large, complicated systems, so simulation is difficult (and sometimes impossible) – Many, many transistors – simulations can last hours/days – Convergence problems These are mixed-signal systems – Noise – Coupling Often require advanced processing and/or post-fabrication correction – Laser trimming – – – Fuses Interaction with DSPs These techniques complicate design/simulation Different from other analog systems – Deal with large signals (not small-signal modeling) 4

Week 1 2 3 4 8 9 10 11 5 6 7 12 13 14 15 Final Date

8/21 8/28 9/4 9/11 9/19 9/25 10/2 10/9 10/16 10/23 10/30 11/6 11/13 11/20 11/27 12/4

Tentative Schedule

Topic

Class Policies Review of Data Converter Subcircuits Review of Data Converter Fundamentals Review of DACs and ADCs Review of Oversampled Converters

Quiz

Project Selection Presentation

Noise in Analog/Mixed-Signal Circuits Noise in Analog/Mixed-Signal Circuits

Quiz

Verilog-A Simulation Presentations

Topic 2 Topic 2 Topic 2

Quiz

FPAA Implementation Presentations

Data Converter State of the Art Data Converter State of the Art Data Converter State of the Art

Design Review Presentations

Thanksgiving Break (No Class)

Quiz

Final Project Presentations

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Expectations Coming into Class

• • • • • • That you will participate!

That you will actually do the reading Emphasis on doing, simulating, and creating That you remember (or can relearn) Cadence That we will be able to find a time to meet outside of class time for brief project updates (for the final project) A willingness to experiment and search for answers 6

CLASS MECANICS

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Reading Assignments/Synopses

• Reading synopses – Short write-ups on what you read – I would expect these to be approximately 2-3 pages of text • Longer more if you include figures – I would highly recommend that you retain a copy of your summaries • Very useful for preparing for quizzes • • Use the provided coversheet – Statement saying that you actually did the reading • Not applicable for the first two weeks – since review only First two weeks is purely review – No required reading – Allen and Holberg chapters 8 and 10 (second edition, available online through the library website) will likely prove useful – – Any way that you can refresh yourself with the information will be acceptable We will be using these ideas all semester long and will be assuming you know them 8

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Class Presentations

Presentation covers a portion of the reading assignments Typically one presentation per person every other week, or so Due midnight the night before the presentation is to be made Target presentation time = 10-15 minutes (if no discussion) – 10-15 minutes should be your guide as to how much detail to include – If you are much shorter, then it means you have left out too much detail – If you are much longer, then it means that you have included too much detail You should become an expert on this subject matter – you are leading the discussion This is a time for discussion!

– Bring your ideas and questions Please, minimize the bullet points. (Do the exact opposite of this presentation) – Pictures are much better 9

Participation in Class

• This class is a group effort, so participation is necessary – Talking, adding ideas, asking questions are all encouraged 10

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Quizzes

Targeted 4 quizzes for the semester The week after the last associate reading assignment was discussed in class Usually around 20-30 minutes Focus on understanding concepts, as opposed to solving problems There will be questions related to the journal paper readings Example questions – What does INL stand for, and what does this concept mean?

– Draw the block diagram of a ramp ADC. Explain the basic operation of this ADC in as much detail as possible. – What was the main contribution by [authors] in [paper name]? This is a time for you to show what you know about what we read and discussed the previous couple of weeks. 11

Mini Projects

• • • • A few smaller projects, mostly leading up to the Final Project Most of these will be useful stepping stones or largely related to the final project Reports are in the form of slides You will present your mini projects during class time 12

Final Project

• • • • • • A complete ADC design! Work in teams of 2 Due during Finals week – Presentation – Simulation – Layout These designs will be fabricated This project will encompass the entire semester, so we will be starting very soon I’m open to suggestions for particular topics, but otherwise, I can help create project ideas 13

Topic 2

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