Field Programmable Analog Arrays (FPAAs) Anthony Chan ECE1352F Presentation

2 FPAAs Why Use Programmable Analog Switched Capacitors – Current Tech Pulse Based – Current Research Future of FPAAs Conclusions Agenda

3 FPAAs Faster Prototyping Faster Time-to-Market Shorter Design Cycles Design integration Improved component matching Why Programmable Analog?

4 FPAAs Structure

5 FPAAs Routing Architecture

6 FPAAs Continuous Time vs. Discrete Time Discrete Time Switched Capacitor Design (Current) Pulse Based Design (Under Research) CAB Implementation

7 FPAAs Switched Capacitor Based Design

8 FPAAs Design of SC circuits quite mature Switches already present in FPAA Allows for better accuracy than RC 0.05% - 0.2% vs. 10% - 30% 0.05% - 0.2% vs. 10% - 30% Benefits of SC Design

9 Currently limited to 1MHz Versatile design possibilities FPAAs Performance of SC Design

10 FPAAs Limitations on switching frequency Require non-overlapping clocks Require non-overlapping clocks Voltage used to represent signal Signal still susceptible to noise Signal still susceptible to noise Increased mixed signal noise Problems with SC Design

11 FPAAs Uses time to represent transmitted signal in the form of PWM Uses of digital signals levels Noise immunity Noise immunity Relatively new area of research Limited functionality Limited functionality Complete design not yet available Complete design not yet available Pulse Based Design

12 FPAAs Pulse Signals

13 FPAAs Pulse Based Integrator

14 FPAAs Pulse Based Performance

15 FPAAs Performance Comparison Voltage DomainPulse Based

16 FPAAs SC designs will dominate commercially Improvements must be acheived Improvements must be acheived FPAAs may lead to FPMAs Natural evolution of mixed-signal design Natural evolution of mixed-signal design Question of viability must be answered FPAAs vs. FPGA comparison FPAAs vs. FPGA comparison 8MHz vs. +1Gbps 8MHz vs. +1Gbps Future of FPAAs

17 FPAAs Programmable Analog has potential SC Designs currently quite functional SC Designs currently quite functional Pulse designs could offer improvement Pulse designs could offer improvement Requires additional development FPAA vs. FPGA needs better analysis Conclusions

18 FPAAs 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, September 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, September 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 A. Hamilton, K. Papathanasiou, “Reconfigurable Analogue Systems: The Pulse-Based Approach”, IEE Proceedings-Computers and Digital Techniques, Vol 147, No. 3, pg , May A. Hamilton, K. Papathanasiou, T. Brandtner, “Palmo: Pulse-Based Signal Processing for Programmable Analog VLSI”, IEEE Transactions on Circutis and Systems II – Analog and Digital Signal Processing, Vol 49, No. 6, pg , June Anadigm Website – References