ENERGY PROCESSORS FOR EH DESIGNS High Efficiency Energy Harvesting-based Power Steve Grady VP Marketing [email protected] Energy Harvesting Overview » Energy can be harvested from almost any environment: » Light, vibration, flow, motion, pressure, magnetic fields, RF, etc. » Energy Harvesting applications include: » Permanently powered wireless sensors, » Hybrid & Active RFID, data logging and access control » Self-Powered Systems need reliable energy storage: » Must have energy storage because EH Transducer energy source is not always available » Self-Powered devices enable inaccessible remote placement and lower installation costs » High battery cycle life enables extended operation – no more service calls » Ideal storage solution is a highly-efficient, eco-friendly, energy storage device that lasts the life of the product 2 Energy Processing for Wireless Sensors Light ΔT Motion Transducer Photovoltaic Thermoelectric Piezoelectric Inductive RF MCU + Radio EM Field Energy Processing Power Conversion Energy Storage Power Management EnerChip ™ CC or EnerChip EP 3 4 Energy Harvesting Transducers Energy Source Challenge Typical Electrical Impedance Typical Voltage Typical Power Output Light Conform to small surface area; wide input voltage range Varies with light input Low kΩ to 10s of kΩ DC: 0.5V to 5V [Depends on number of cells in array] 10µW-15mW (Outdoors: 0.15mW-15mW) (Indoors: <500µW) Vibrational Variability of vibrational frequency Constant impedance 10s of kΩ to 100kΩ AC: 10s of volts 1µW-20mW Thermal Small thermal gradients; efficient heat sinking Constant impedance 1Ω to 100s of Ω DC: 10s of mV to 10V 0.5mW-10mW (20°C gradient) RF & Inductive Coupling & rectification Constant impedance Low kΩs AC: Varies with distance and power 0.5V to 5V Wide range EH Transducer – Variable Impedance Example: Photovoltaic Cell 5 EH Transducer – Constant Impedance Examples: Thermoelectric Generators, Piezoelectric Materials, Electromagnetic 6 Matching Impedance is Critical RT RT RT 10KΩ Energy Processing Stage RL Reach PMAX when RT = RL 100Ω Impedance mismatch means significant lost power RL EP stage matches transducer impedance for high efficiency power conversion and optimal power management to load 7 8 EnerChip CC Energy Harvester and Battery » Solid State Battery with Integrated Charge Control » » » » » Reflow tolerant, surface mount technology and assembly process 3.3V compatibility, power-fail detect and automatic back-up Drop-in solution, small footprint and minimal external component count Thousands of recharge cycles, low self-discharge, flat VOUT Single-Chip Energy Harvesting Solution EnerChip CC 20-pin DFN Package Energy Processor for Max Peak Power » CBC915 Energy Processor - Universal Energy Harvesting Device: » Supports Multi-Modes of EH: Electromagnetic, Photo Voltaic, Thermo-Electric & Piezoelectric » Enables system to be “Energy Aware” provides harvester status to system » Achieves high-efficiency conversion – 70%-90% 9 Cymbet CBC915 Energy Processor 10 » High-Efficiency, Universal Energy Harvesting Device » Supports Maximum Power Point Tracking (MPPT): » Dynamically matches output impedance of EH Source device to load • Provides Energy Awareness to host: – Conveys harvester status to host system via I2C interface – Monitors & reports whether EH system is running from harvested or stored energy – Input power measurement and status reporting – Enables “Coulomb counting” by host system 11 EVAL-09 Universal Energy Harvesting Kit Thermoelectric Generator (TEG) or RF Induction or Photovoltaic Cell or Electromagnetic or Piezoelectric Generator CC2500 Radio Various Transducer Interface Electronics Energy Processor CBC915 EnerChip Energy Storage MSP430 with Temperature Sensor Available at www.avnetexpress.avnet.com keyword Eval-09