Datasheet

ATmega164A/PA/324A/PA/644A/PA/1284/P
 2018 Microchip Technology Inc. Data Sheet Complete DS40002070A-page 15
timer base while the rest of the device is sleeping. The ADC Noise Reduction mode stops the CPU and all I/O
modules except Asynchronous Timer and ADC, to minimize switching noise during ADC conversions. In
Standby mode, the Crystal/Resonator Oscillator is running while the rest of the device is sleeping. This allows
very fast start-up combined with low power consumption. In Extended Standby mode, both the main Oscillator
and the Asynchronous Timer continue to run.
Microchip offers the QTouch library for embedding capacitive touch buttons, sliders and wheels functionality into
AVR microcontrollers. The patented charge-transfer signal acquisition offers robust sensing and includes fully
debounced reporting of touch keys and includes Adjacent Key Suppression
™ (AKS™) technology for
unambiguous detection of key events. The easy-to-use QTouch Suite toolchain allows you to explore, develop
and debug your own touch applications.
The device is manufactured using the high-density nonvolatile memory technology. The On-chip ISP Flash
allows the program memory to be reprogrammed in-system through an SPI serial interface, by a conventional
nonvolatile memory programmer, or by an On-chip Boot program running on the AVR core. The boot program
can use any interface to download the application program in the application Flash memory. Software in the
Boot Flash section will continue to run while the Application Flash section is updated, providing true Read-
While-Write operation. By combining an 8-bit RISC CPU with In-System Self-Programmable Flash on a
monolithic chip, the ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P is a powerful microcontroller
that provides a highly flexible and cost effective solution to many embedded control applications.
The ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P is supported with a full suite of program and
system development tools including: C compilers, macro assemblers, program debugger/simulators, in-circuit
emulators, and evaluation kits.
2.2 Comparison between ATmega164A, ATmega164PA, ATmega324A, ATmega324PA,
ATmega644A, ATmega644PA, ATmega1284 and ATmega1284P
2.3 Pin Descriptions
2.3.1 VC
Digital supply voltage.
2.3.2 GND
Ground.
Table 2-1. Differences between ATmega164A, ATmega164PA, ATmega324A, ATmega324PA, ATmega644A,
ATmega644PA, ATmega1284 and ATmega1284P
Device Flash EEPROM RAM Units
ATmega164A 16K 512 1K
bytes
ATmega164PA 16K 512 1K
ATmega324A 32K 1K 2K
ATmega324PA 32K 1K 2K
ATmega644A 64K 2K 4K
ATmega644PA 64K 2K 4K
ATmega1284 128K 4K 16K
ATmega1284P 128K 4K 16K