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ATMEGA644PA-MU

MCHPATMEGA644PA-MU

Microchip Technology
Closer mid-range alternative with more Flash than 328P but typically less than 1284P.
NRND619 in stock
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Overview

The ATMEGA644PA-MU is a high-performance, low-power 8-bit AVR RISC-based microcontroller featuring 64KB of Flash memory and 4KB of SRAM. This device bridges the gap between the popular ATmega328P and larger ATmega1284P, providing 32 I/O lines and a 20MHz maximum clock speed in a compact 44-VQFN package.

Why Choose This Part

The ATMEGA644PA-MU offers a balanced memory-to-pin-count ratio, providing twice the Flash and SRAM of the ATmega328P while maintaining a low-power profile. Its advanced RISC architecture executes most instructions in a single clock cycle, achieving throughput near 1 MIPS per MHz.

Applications

Capacitive Touch Interfaces
Utilizes the QTouch library support to implement buttons, sliders, and wheels with minimal external components.
Industrial Controller Nodes
The 32 I/O pins and dual USART connectivity make it suitable for managing multiple sensors and industrial communication protocols.
Battery-Powered Instrumentation
Features ultra-low power consumption with a sleep current of 0.6uA and multiple power-saving modes like ADC Noise Reduction.
Embedded Data Logging
Equipped with 2KB of internal EEPROM for non-volatile storage of calibration data and system logs.

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-VFQFN Exposed Pad
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-VQFN (7x7)
Voltage - Supply (Vcc/Vdd) 1.8V ~ 5.5V

Getting Started

Developers can use the Microchip Studio (formerly Atmel Studio) or the MPLAB X IDE along with the AVR GCC toolchain for firmware development. Hardware debugging and programming are supported via the Atmel-ICE or Power Debugger using the JTAG or ISP interfaces.

ATMEGA644PA Family

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

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

Also Consider

ATmega1284P MCHPMicrochip Technology - Doubles the Flash to 128KB and significantly increases SRAM to 16KB for memory-intensive applications.
ATmega328P MCHPMicrochip Technology - A smaller, more cost-effective alternative for projects that only require 32KB of Flash and 2KB of SRAM.
ATmega644PA (DIP) MCHPMicrochip Technology - The same silicon in a 40-pin PDIP package for easier breadboarding and through-hole assembly.

Categories

Consumer Electronics > Touch & Gesture Control
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