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Member Since: December 6, 2010

Country: Belgium

  • Could anyone enlighten me as to why Sparkfun doesn't like using the exposed pads on these things? The Pro Micro doesn't have one either. They must be there for some reason, no? I'm currently designing an Atxmega32u4 board, and it seems even the Atmel datasheet doesn't say anything specific about whether the exposed pad should be connected to anything... weird.

  • I figured it out, so I'm going to answer my own question here: 3.7V in the battery datasheet is the average voltage, 4.20 is the maximum 'starting' voltage of the battery. It will stop charging at that point. Since the MCP73831T regulates to 4.20V, this is a suitable charger.

  • From the MCP73831T datasheet, it looks like this IC regulates the output voltage to one of 4 options: 4.20V, 4.35V, 4.40V, 4.50V. Correct?
    If so, how is it suitable to charge a single cell 3.7V li-poly battery? The datasheet for the batteries you carry says 'Charge cut-off Voltage' is 4.20±0.03V. Seems really close.
    What am I missing?

No public wish lists :(