LT1300 Solar Powered Power Supply

This architecture was generated as allotment of a alien acclimate base project. One of the requirements of the architecture is that it accept a solar-powered accumulation with rechargeable batteries. This architecture is based on a photovoltaic arrangement accessible from Radio Shack alleged a BatterySAVER (part cardinal 980-1045). It was advised to allegation your car array during the day. They allegedly aren't actual accepted because you can aces them up for $15. The affidavit claims an achievement of 1 watt but I begin that at apex in Atlanta, the ability was a little les than bisected a watt. Maybe at the equator during the autumnal equinox...




 

 LT1300 Solar Powered Power Supply 

 
For my application, the boilerplate cesspool off the batteries would is abundant abate than the charging accepted (50mA). If your appliance has college boilerplate accepted requirements, again R1 will charge to be adapted accordingly:

R1=64mV/(50mA+Average Amount Current)

Don't try to cull too abundant accepted admitting because the solar console can alone accommodate 500mW and the batteries charge 40% of that. That leaves 300mW for your load.

The architecture is based on four anatomic blocks: 1) a 50mA accepted antecedent apprenticed by the solar cells, 2) three AAA NiCAD batteries with a 500mAHr capacity, 3) a 5V, 400mA switch mode regulator, and 4) a low dropout 3.3V 150mA beeline regulator. If you accept no charge for 3.3V again U3 and C4 can be eliminated. If you alone charge 3.3V again U3 and C4 can be alone and pin 2 of U2 can be affiliated to arena - this will catechumen U2 to a 3.3V switch mode regulator.

All the capacitors on the switch mode ability accumulation should be tantalum with C2 actuality affiliated anon to pins 6 and 8 if possible.