My Research Topics st Robu Low Robust er

My Research Topics st Robu Low Robust er Pow LSI V Power VLSI Alicia Klinefelter Dept. of Electrical Engineering, University of Virginia January 23, 2012

Areas § Cyber-physical Systems (CPS) [1] § Deliverable: Hardware for CPS system § NEMO § Deliverable: Whale tag § All-Digital Phase-Locked Loop (ADPLL) [2] § Have taped out § Testing is next st Robu Low er Pow VLSI § Simulink Model For Ultra. Low Power Systems [1] http: //www. imec. be/Scientific. Report/SR 2008/HTML/1225020. html [2] http: //hamptonroads. com/2008/08/researchers-tag-whales-track-ships-sonar-study 2

Context/Problems § CPS § Context: Want to combine the cyber (computational) and physical (body) aspects of body sensor nodes to create a network. § Problem: Incorporating multiple disciplines in one project and choosing the right architecture. § NEMO § Context: Debate exists on whether whales are affected by sonar from submarines. Record the sounds the whale hears and the depth and length of its dives. § Problem: Low-power chip that can interface with non-volatile memory and interface to a variety of sensors. Determine divide between analog and digital processing. § ADPLL st Robu Low er Pow VLSI § Context: Result of a class project on PLL’s § Problem: Most ADPLLs consume m. W of power and still contain analog components. 3

Approach/Findings § CPS § Approach: Work on modeling system architecture. In the meantime, develop plan for hardware. § Findings: Comprehensive model is difficult to pin down. § NEMO § Approach: Model small sections of the system (NVM interface, interfacing to sensors) § Hope to find: Analog/Digital partition, low-power signal processing. § ADPLL st Robu Low er Pow VLSI § Approach: Replace analog elements with digital elements and operate in sub-threshold for a coarse clock. § Findings: Sub-threshold limits max operating frequency of ringoscillator, accuracy of time-to-digital converter, and time to lock. 4

Questions? st Robu Low er Pow VLSI 5