Summary datasheet for the ATmega325, ATmega3250, ATmega645 and ATmega6450 AVR microcontrollers, a 231 KB PDF. As the short edition, it typically provides the feature list, pinouts for the different packages, pin descriptions and ordering codes. It is convenient for fast identification of pins when probing a board or checking a replacement part. For registers, fuses and detailed electrical figures, use the full datasheet of this family, and confirm the pin count before reading any diagram.
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