EVIX-CX3AA IXYS-DIRECTED ENERGY, EVIX-CX3AA Datasheet

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... EVIX-CX3AA Application Note Introduction The EVIX-CX3AA solar charging evaluation board demonstrates several IXYS technologies in a simple solar charger for a single AA rechargable alkaline battery. The circuit represents an improvement over the the typical solar cell charger that uses a blocking rectifier diode to prevent back discharge from the battery when no sun light is present. Instead, it uses a MOSFET as the blocking mechanism and a small solar cell to power the gate of the MOSFET to turn it on and off ...

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Background Some basic information needs to be covered to better understand what to expect in terms of the evaluation board’s performance with regards to solar cell type, lighting conditions in terms of power density, and general industry standards as they ...

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Fig. 2 Relative Light Power Densities Relative Lighting Power Density Figure 2 compares relative power density for various lighting conditions in units of Watts per square meter (W/m ). The reference standard condition is 1 Sun and is equal to ...

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... In the opposite sense, the charge rate capacity is the ability to supply current (power) over time to the battery. Trickle charging of alkaline cells is usually done at 0.1C or less. The EVIX-CX3AA evaluation board charges with a maximum current of about direct bright sunlight (1 Sun), hours to charge. There are a number of battery chemistries available in AA size packages, but we ...

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Component Description IXYS XOB17-12x1 Solar Cell The battery charging current is generated by three series-connected IXYS XOB17-12x1 s. Each of these monocrystalline, high-efficiency solar cells generates 0.63 V open SolarBIT circuit voltage and 42 mA short circuit current (0.51 V ...

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Test Results Battery Discharge Test To provide an additional set of data for the battery capacity, a 22-ohm resistor was con- nected across a fresh battery to continuously discharge it down to 0.8V. The voltage across the resistor was measured ...

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Fig. 6 Battery Discharge Current Battery Charge Test Using the battery that was discharged in the previous section, an experiment was run to see how long it would take to recharge it using solar power. The current from the solar ...

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... Device Datasheet Links IXYS XOB17 Solar Cell http://ixdev.ixys.com/DataSheet/XOB17-Solar-Bit-Datasheet_Mar-2008.pdf IXYS IXTY12N06T Power MOSFET http://ixdev.ixys.com/DataSheet/99947.pdf Clare CPC1832N Solar Cell http://www.clare.com/home/pdfs.nsf/www/CPC1832.pdf/$file/CPC1832.pdf EVIX-CX3AA Bill Of Materials Qty Part Description 3 SolarBIT 1 Solar Bulb 2 ...