Multi channel battery charger

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This page describes a charger for multiple XO Laptop batteries.

Introduction

Code name "Supercharger"

Input Power

• 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.
  • DC connector is not yet finalized
• 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/projects/supercharger

Function

• Approximately 2 hours for complete charge
  • Maximum number of simultaneous charging channels
    • 15 Batteries on AC
    • 10 Batteries via 150W DC source
    • 8 Batteries via 2 60W solar blankets
    • 4 Batteries via 1 60W blanket

Datasheets

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