Energy Processors for EH Designs

ENERGY PROCESSORS FOR EH DESIGNS
High Efficiency Energy Harvesting-based Power
Steve Grady
VP Marketing
sgrady@cymbet.com
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
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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
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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
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EH Transducer – Constant Impedance
Examples: Thermoelectric Generators, Piezoelectric Materials, Electromagnetic
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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
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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%
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Cymbet CBC915 Energy Processor
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» 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
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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