DS-72-40 Datasheet, PDF (17/17 Pages) Cymbet Corporation – EnerChip™ CC Energy Harvester Evaluation Kit

CBC-EVAL-10B EnerChip CC EH Evaluation Kit
Power Conversion Efficiency Considerations
System factors such as PV cell properties; ambient light; input and output capacitor sizes; battery state-of-
charge; and CBC3150 VMODE/input POR peak power voltage point setting will all affect the duty cycle of the
CBC3150 charge pump and system power conversion efficiency.
The CBC3150 has a built-in latency of about 200ms with respect to the timing of RESET/ being asserted low
af¬ter the charge pump is disabled. For optimum power conversion efficiency, size the input capacitor so that
it will only charge one or two tenths of a volt during that 200ms period under the lowest anticipated lighting
condition - that is, where the PV cell gives its lowest power output.
For example, suppose the PV cell at 200Lux can deliver 50µA at a maximum power point of 3.0V. Transposing
the standard equation I = C x dv/dt, the input capacitor can be sized as C = 50µA x 200ms/100mV = 100µF of
capacitance. When the charge pump runs, it will quickly pump the capacitor to the switching point. When the
charge pump stops during the 200ms latency time, the capacitor will not charge above the maximum power
point. At higher light intensity, the efficiency is less important and thus the capacitor does not need to be over-
sized to maintain operation at the peak power point of the PV cell.
Ordering Information - Products Discontinued and Not Available
EnerChip Part Number
CBC-EVAL-10B
CBC3150-D9C
CBC050-M8C
Description
EnerChip CC Energy Harvester
Evaluation Kit
EnerChip CC with Integrated Power
Management
EnerChip 50µAh Solid State
Battery
Notes
Contains Solar Cell Panel and
CBC51100 Module
Packaged in Tape and Reel or
Tubes
Packaged in Tape and Reel or
Tubes
Disclaimer of Warranties; As Is
The information provided in this data sheet is provided “As Is” and Cymbet Corporation disclaims all representations or warranties of any
kind, express or implied, relating to this data sheet and the Cymbet battery product described herein, including without limitation, the
implied warranties of merchantability, fitness for a particular purpose, non-infringement, title, or any warranties arising out of course of
dealing, course of performance, or usage of trade. Cymbet battery products are not approved for use in life critical applications. Users shall
confirm suitability of the Cymbet battery product in any products or applications in which the Cymbet battery product is adopted for use and
are solely responsible for all legal, regulatory, and safety-related requirements concerning their products and applications and any use of
the Cymbet battery product described herein in any such product or applications.
Cymbet, the Cymbet Logo and EnerChip are trademarks of Cymbet Corporation. All Rights Reserved.
EnerChip products and technology are covered by one or more patents or patents pending.
©2014 Cymbet Corporation • Tel: [phone] • www.cymbet.com
DS-72-40 Rev C

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