Short-form summary datasheet covering the Atmel ATmega329, ATmega3290, ATmega649 and ATmega6490 microcontrollers, AVR parts with integrated LCD controllers. The 4-digit variants come in larger packages with more pins. This 263 KB PDF gives the feature list, pin configurations, package outlines and ordering information rather than full register descriptions. Technicians use it for fast pin identification while probing or swapping chips, then turn to the complete datasheet for timing, fuse and peripheral details. Readable in any PDF program.
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