1 5. Application Examples 5.1. Programmable compensation for analog circuits (Optimal tuning) 5.2. Programmable delays in high-speed digital circuits (Clock skew compensation) 5.3. Automated discovery – Invention by Genetic Programming (Creative Design) 5.4. EDA Tools, analog circuit design 5.5. Adaptation to extreme temperature electronics (Survivability by EHW) 5.6. Fault-tolerance and fault-recovery 5.7. Evolvable antennas (In-field adaptation to changing environment) 5.8. Adaptive filters (Function change as result of mission change) 5.9 Evolution of controllers

2 Adaptation to extreme temperature electronics (Survivability by EHW) Extreme environments - temperature, radiation –Space, defense, commercial Recovery of degraded behavior via evolutionary reconfiguration (Temperature compensation via architectural changes) Extreme temperature circuits through evolutionary design –Robust circuits (wide range of operation) –Designed for the extreme temperature Diehard electronics (controls need also to survive)

3 Expanding Operational Envelope through Adaptive Reconfiguration (A Circuit Solution) Claim: Circuits solutions can further expand the operational envelope, and should be considered in addition to device solutions Temperature Circuit (reconfiguration) solutions Bulk CMOS Limitations are of the ensemble device/configuration, not of the device(material) only Devices/material solutions (e.g SOI) +250 C-200 C Radiation

4 {T1, D(T1), C1} -> F {T2, D(T2), C1} -> G {T2, D(T2), C2} -> F Expanding Device Operational Envelope through Adaptive Reconfiguration Background: High temperature operation: drastic change in device parameters;Limit for silicon (below 100V) : 250 o C; Main MOS transistors parameters dependent on temperature: Threshold voltage, mobility, Fermi potential. EHW can preserve/ recover system functionality by reconfiguration/morphing. If device characteristics change with temperature, one can preserve the function by finding a different circuit solution, which exploits the altered/modified characteristics

5 Steps of the temperature experiments 1. Get human design or evolutionary design of a circuit at 27 C 2. Expose chip to low/high temperature and observe degraded response 3. Apply evolution, and obtain a new circuit solution, which recovers functionality

6 (a). High temperature experimental setup with heat pump and chip under test (b). Temperature measurement with thermocouples above and below the die (c) Picture of the apparatus (d)Photo of the heated chip with infrared camera High temperature testbed

7 T=27C Functional response of original circuit affected by temperature Functional response of original circuit design F T= -196 C Repaired functional response of evolved new circuit configuration F Functional Recovery at Low Temperatures T= -196 C G

8 T: -196CT: +27CT: =+245C Input1: 2.5Volt Input2: Ramp 0Volt to 5Volt Output Current bias Current bias Current bias changes Continuous adaptation to temperature via reconfiguration Circuits evolved at-196C, +27C and +245C

9 Wrong logic response at high temperature ‘1’ instead of ‘0’ Degradation of logic circuits with temperature

10 Evolution can automatically (on-chip, in-situ) find circuit solutions that recover lost functionality, thus expanding the operational envelope of current devices 1g 1d 2g 2d 4s 4g 3g 3d4d 6d 6g5g 5d 6s5s 7d 7g 8d 8g In1 In2 Out AND Gate evolved at 27 C Recovered by as 3.3V 1g 1d 2g 2d 4s 4g 3g 3d4d 6d 6g5g 5d 6s5s 7d 7g 8d 8g AND Gate recovered at 180 C Expanding the temperature operational range through circuit reconfiguration

11 Measured Measured 3.3VCompliant AND circuit evolved at 27C degrades as temperature increases Evolved at 240C becomes compliant; however this circuit degrades when temperature decreases Solutions evolved are point solutions; continuous monitoring and evolution is needed

12 Evolution can recover functionality of circuits affected by faults and degradation, by finding a new circuit bypassing the fault or using damaged components in a different configuration. Experiments at low (-196 C) and high (>+300 C) demonstrate that electronic functions altered by temperature can be recovered through reconfiguration. Coping with faults and degradation in extreme environments

13 High temperature recovery of various circuits: OpAmp, DAC, filters Reconfigurable Cell (FPTA-2) –8 cells: 0,1,2,3,4,5,6,7. –Input: 4 Digital Inputs (0 to 2 Volt – 10 kHz) Genetic Algorithm –400 individuals –Chromosome: 500 bits –less than 50 generations – 1 min

14 Robust circuits (wide range of operation) Conditions for evolution: maintain behavior over a wide range: new designs, possible trade-offs (size, accuracy, speed) Need silicon validation – high temperature SPICE models may be less accurate

15 Circuits designed specifically for high temperatures (only) Evolve circuits that work at temperature beyond that of conventional cells Vdd In1 In2 Out Vdd Conventional AND gate deteriorates at 320oC Evolution synthesized AND gate operating at 320oC. In1 In2 50p Out Vdd 27C 320C Topology + Parameters (W/L) Silicon validation needed; potential model inaccuracy of the model

16 Diehard electronics How do we make sure the hardware running the evolutionary algorithms is not itself affected by temperature? Analog functions are usually more sensitive (narrower specs, less noise margin) and will generally go first. However we only have experiments with reconfigurable HW under temperature extremes. One can accommodate some designs (either for controlling algorithm or for specific function) specific for certain environment, kicking in only there