Field Programmable Analog Arrays (FPAAs)

1. Field Programmable Analog Arrays (FPAAs) Anthony Chan ECE1352F Presentation

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

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

4. FPAAs Structure

5. FPAAs Routing Architecture

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

7. FPAAs Switched Capacitor Based Design

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

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

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

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

12. FPAAs Pulse Signals

13. FPAAs Pulse Based Integrator

14. FPAAs Pulse Based Performance

15. FPAAs Performance Comparison Voltage Domain Pulse Based

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

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

18. FPAAs References 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 1998 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, September 1998 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 1998 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, May 2000 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 Digital Signal Processing, Vol 49, No. 6, pg 379-387, June 2002 6. Anadigm Website – www.anadigm.com