Complete datasheet for the ATmega164, ATmega324 and ATmega644 AVR microcontrollers, a 2.66 MB PDF.

Family manual for the Atmel AVR XMEGA D series, a 5.25 MB PDF describing the core, memories, clock system, power management, ports, timers, communication peripherals…

Datasheet in PDF form for the Atmel ATmega323, an older 8-bit AVR microcontroller with in-system programmable flash, EEPROM, SRAM and JTAG interface.

Family manual for the Atmel AVR XMEGA A series, a 4.96 MB PDF that explains the CPU, DMA, event system, clocks, power management, timers, USART, SPI, TWI, ADC, DAC…

Datasheet for the Texas Instruments TPS51219, a single-phase synchronous buck controller often used for memory or system rails on laptop motherboards, provided as a 1.23…

Complete datasheet in PDF form, 1.23 MB, for the tiny26, which corresponds to the Atmel AVR ATtiny26 8-bit microcontroller. No revision is given in the name.