Summary datasheet for the ATmega406 AVR microcontroller, a 179 KB PDF. The ATmega406 is aimed at smart battery management, so this part often turns up inside laptop and tool battery packs. The short edition gives features, pinout and package information, enough to identify cell voltage inputs, supply and programming pins while diagnosing a pack. Detailed register and electrical chapters are omitted here; consult the full ATmega406 datasheet before attempting to read or rewrite the chip firmware.
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