Field Programmable Field Programmable Analog Arrays (FPAAs)Analog Arrays (FPAAs)

Anthony ChanAnthony Chan

ECE1352F Presentation

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Why Use Programmable AnalogWhy Use Programmable AnalogSwitched Capacitors – Current TechSwitched Capacitors – Current TechPulse Based – Current ResearchPulse Based – Current ResearchFuture of FPAAsFuture of FPAAsConclusionsConclusions

AgendaAgenda

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Faster PrototypingFaster PrototypingFaster Time-to-MarketFaster Time-to-MarketShorter Design CyclesShorter Design CyclesDesign integrationDesign integrationImproved component matchingImproved component matching

Why Programmable Analog?Why Programmable Analog?

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StructureStructure

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Routing ArchitectureRouting Architecture

66

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Continuous Time vs. Discrete TimeContinuous Time vs. Discrete Time

Discrete TimeDiscrete TimeSwitched Capacitor Design (Current)Switched Capacitor Design (Current)Pulse Based Design (Under Research)Pulse Based Design (Under Research)

CAB ImplementationCAB Implementation

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Switched Capacitor Based DesignSwitched Capacitor Based Design

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Design of SC circuits quite matureDesign of SC circuits quite matureSwitches already present in FPAASwitches already present in FPAAAllows for better accuracy than RCAllows for better accuracy than RC 0.05% - 0.2% vs. 10% - 30%0.05% - 0.2% vs. 10% - 30%

Benefits of SC DesignBenefits of SC Design

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Currently limited to 1MHzCurrently limited to 1MHzVersatile design possibilitiesVersatile design possibilities

FPAAsFPAAs

Performance of SC DesignPerformance of SC Design

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Limitations on switching frequencyLimitations on switching frequency Require non-overlapping clocksRequire non-overlapping clocks

Voltage used to represent signalVoltage used to represent signal Signal still susceptible to noiseSignal still susceptible to noise

Increased mixed signal noiseIncreased mixed signal noise

Problems with SC DesignProblems with SC Design

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Uses time to represent transmitted Uses time to represent transmitted signal in the form of PWMsignal in the form of PWMUses of digital signals levelsUses of digital signals levels Noise immunityNoise immunity

Relatively new area of researchRelatively new area of research Limited functionalityLimited functionality Complete design not yet availableComplete design not yet available

Pulse Based DesignPulse Based Design

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Pulse SignalsPulse Signals

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Pulse Based IntegratorPulse Based Integrator

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Pulse Based PerformancePulse Based Performance

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Performance ComparisonPerformance Comparison

Voltage Domain Pulse Based

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SC designs will dominate commerciallySC designs will dominate commercially Improvements must be acheivedImprovements must be acheived

FPAAs may lead to FPMAsFPAAs may lead to FPMAs Natural evolution of mixed-signal designNatural evolution of mixed-signal design

Question of viability must be answeredQuestion of viability must be answered FPAAs vs. FPGA comparisonFPAAs vs. FPGA comparison 8MHz vs. +1Gbps8MHz vs. +1Gbps

Future of FPAAsFuture of FPAAs

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Programmable Analog has potentialProgrammable Analog has potential SC Designs currently quite functionalSC Designs currently quite functional Pulse designs could offer improvementPulse designs could offer improvement

Requires additional developmentRequires additional developmentFPAA vs. FPGA needs better analysisFPAA vs. FPGA needs better analysis

ConclusionsConclusions

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1. D. R. D’Mello, P. G. Gulak, “Design Approaches to Field-Programmable Analog Integrated 1. D. R. D’Mello, P. G. Gulak, “Design Approaches to Field-Programmable Analog Integrated Circuits”, Analog Integrated Circutis and Signal Processing, Vol 17, No. 1-2, pg 7-35, Circuits”, Analog Integrated Circutis and Signal Processing, Vol 17, No. 1-2, pg 7-35, September 1998September 1998

2. H. Kutuk, S. M. Kang, “A Switched Capacitor Approach to Field-Programmable Analog Array 2. H. Kutuk, S. M. Kang, “A Switched Capacitor Approach to Field-Programmable Analog Array Design”, Analog Integrated Circutis and Signal Processing, Vol 17, No. 1-2, pg 51-65, Design”, Analog Integrated Circutis and Signal Processing, Vol 17, No. 1-2, pg 51-65, September 1998September 1998

3. A. Bratt, I. Macbeth, “DPAD-2 A Field Programmable Analog Array”, Analog Integrated 3. A. Bratt, I. Macbeth, “DPAD-2 A Field Programmable Analog Array”, Analog Integrated Circutis and Signal Processing, Vol 17, No. 1-2, pg 67-89, September 1998Circutis and Signal Processing, Vol 17, No. 1-2, pg 67-89, September 1998

4. A. Hamilton, K. Papathanasiou, “Reconfigurable Analogue Systems: The Pulse-Based 4. A. Hamilton, K. Papathanasiou, “Reconfigurable Analogue Systems: The Pulse-Based Approach”, IEE Proceedings-Computers and Digital Techniques, Vol 147, No. 3, pg 203-207, Approach”, IEE Proceedings-Computers and Digital Techniques, Vol 147, No. 3, pg 203-207, May 2000May 2000

5. A. Hamilton, K. Papathanasiou, T. Brandtner, “Palmo: Pulse-Based Signal Processing for 5. A. Hamilton, K. Papathanasiou, T. Brandtner, “Palmo: Pulse-Based Signal Processing for Programmable Analog VLSI”, IEEE Transactions on Circutis and Systems II – Analog and Programmable Analog VLSI”, IEEE Transactions on Circutis and Systems II – Analog and Digital Signal Processing, Vol 49, No. 6, pg 379-387, June 2002Digital Signal Processing, Vol 49, No. 6, pg 379-387, June 2002

6. Anadigm Website – 6. Anadigm Website – www.anadigm.comwww.anadigm.com

ReferencesReferences