Device datasheet for the Atmel ATxmega A4 series, the 44-pin members of the AVR XMEGA A family. The 3.75 MB PDF provides pin assignments, memory options per device, package outlines, DC and AC characteristics and silicon errata. For peripheral register details it should be read together with the XMEGA A manual. Technicians use it to identify supply and PDI programming pins, check clock sources and confirm a replacement part fits. Remember these chips are low-voltage devices limited to around 3.6 V supply.
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