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ATMEGA644PA-AU

MCHPATMEGA644PA-AU

Microchip Technology
Offers a mid-point with 64 KB flash and similar AVR peripherals for projects that need more resources than an ATmega328P but less than a 1284P.
NRND1,042 in stock
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Overview

The ATMEGA644PA-AU is a high-performance, low-power 8-bit AVR RISC-based microcontroller featuring 64 KB of ISP Flash memory and 4 KB of SRAM. It serves as a middle-ground solution in the AVR family, providing more memory and I/O than the ATmega328P without the footprint or cost of the ATmega1284P. With 32 general-purpose I/O lines and an on-chip 2-cycle multiplier, it is optimized for efficient processing in embedded control systems.

Why Choose This Part

This MCU offers a balanced 64 KB Flash and 4 KB RAM profile that accommodates larger software stacks and RTOS kernels better than entry-level 8-bit chips. It features the picoPower architecture for ultra-low power consumption in sleep modes and includes 131 instructions for high-efficiency code execution.

Applications

Industrial Control Systems
Utilizing 32 I/O lines and integrated PWM for managing actuators, sensors, and local control loops.
Capacitive Touch Interfaces
Leveraging QTouch library support for implementing buttons, sliders, and wheels in user interface panels.
Battery-Powered Instrumentation
Taking advantage of the 0.5uA power-down mode and wide operating voltage for long-term remote monitoring.
Communication Bridges
Using dual USARTs, SPI, and I2C to act as a protocol converter between various industrial peripherals.

Key Specifications

Speed 20MHz
RAM Size 4K x 8
Core Size 8-Bit
EEPROM Size 2K x 8
Peripherals Brown-out Detect/Reset, POR, PWM, WDT
Connectivity I2C, SPI, UART/USART
Mounting Type Surface Mount
Number of I/O 32
Core Processor AVR
Package / Case 44-TQFP
Data Converters A/D 8x10b
Oscillator Type Internal
Program Memory Size 64KB (32K x 16)
Program Memory Type FLASH
Operating Temperature -40degC ~ 85degC (TA)
Supplier Device Package 44-TQFP (10x10)
Voltage - Supply (Vcc/Vdd) 1.8V ~ 5.5V

Getting Started

Development is primarily supported through Microchip Studio or the MPLAB X IDE using the XC8 compiler. Hardware debugging and programming are typically performed via the JTAG interface or ISP using the MPLAB PICkit 5 or Atmel-ICE programmers. For rapid prototyping, the part is compatible with various AVR-based breakout boards and the standard Arduino software environment through third-party core definitions.

ATMEGA644PA Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number Package Stock
ATMEGA644PA-AU (this part) TQFP-44 1,042
ATMEGA644PA-PU DIP-40 1,041
ATMEGA644PA-MU VFQFN-44 619

Also Consider

ATMEGA1284P-AU MCHPMicrochip Technology - Provides a direct upgrade path with 128 KB Flash and 16 KB SRAM in the same 44-TQFP footprint.
ATMEGA328P-AU MCHPMicrochip Technology - A more cost-effective and common alternative if your application fits within 32 KB Flash and 2 KB RAM.
ATMEGA644PA-PU MCHPMicrochip Technology - The PDIP-40 through-hole version of the same silicon for easier breadboarding and prototyping.

Categories

Consumer Electronics > Touch & Gesture Control
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