Multi channel battery charger

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Multi Channel Battery Charger

== 

• AC Power 100V-230V. 300W
• DC 10V-28V. 150W

Exterior Connections

• AC In: IEC for 120/220VAC
• DC In: 10VDC to 28VDC 2 Pin connector that mates with whats on the GP solar blanket.
• USB B connector (Its a USB device)
• 2 cables with XO DC jacks on them

Electrical Misc

• The CPU is an Atmel At91SAM7x family part.
  • See http://www.atmel.com/dyn/products/product_card.asp?part_id=3754
• The per battery DC-DC charger is a SEPIC design based around a MicroChip MCP1631 part

Software

• Forth/C combination.
• http://dev.laptop.org/git?p=projects/supercharger;a=summary

Mechanical

• Density. Getting as many batteries as possible in as small a footprint is a goal.

• Physical Safety. Its got to be stable and hold lots of heavy batteries but not be able to fall over on top of a child who might be trying to climb on it to get his battery.

• Stackable. More vertical space is available than floor sq footage so an idea was to make them stackable. But see above point.

• Heat dissipation. Input stage power supply is about 85% (DC/DC may be higher). 2nd stage is 82%. So while on DC heat dissipation will be around 64 Watts and on AC around 98 Watts. (Calculated. Not yet measured)

• Enclosure. Metal. Except perhaps for some plastic for the battery holder. Having metal available to heatsink to should help in keeping the electronics from burning up in hot countries.

Datasheets

• File:At91sam7x128 256 pc.pdf Atmel CPU
• File:DS2756.pdf DS2756