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ATmega328P

MCHPATmega328P

Microchip Technology
Popular AVR alternative for projects that do not require native USB but benefit from wide ecosystem and low-cost modules.
Active13,074 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The ATmega328P is a high-performance, low-power 8-bit AVR RISC-based microcontroller featuring 32KB of ISP flash memory and 1024 bytes of EEPROM. It is optimized for low power consumption, achieving as low as 0.2uA in shutdown mode while providing a rich set of peripherals like a 2-cycle multiplier and a Peripheral Touch Controller.

Why Choose This Part

The ATmega328P offers an exceptional balance of power efficiency and ease of use, supported by one of the largest open-source software ecosystems in existence. Its wide operating voltage range of 1.8V to 5.5V and 27 I/O pins make it highly versatile for interfacing with both legacy 5V logic and modern low-voltage sensors.

Applications

Battery-Powered Sensors
Utilizes extreme low-power sleep modes (1.3uA in power-save) to extend the life of remote wireless nodes and environmental monitors.
HMI Touch Interfaces
Leverages the integrated Peripheral Touch Controller (PTC) for implementing capacitive buttons, sliders, and wheels without external ICs.
Industrial Control
Uses the internal calibrated oscillator, programmable brown-out detection, and 20MHz clock speed for reliable logic control in space-constrained modules.

Key Specifications

Speed 20MHz
RAM Size 2K x 8
Core Size 8-Bit
EEPROM Size 1K x 8
Peripherals Brown-out Detect/Reset, POR, PWM, WDT
Connectivity I2C, SPI, UART/USART
Mounting Type Surface Mount
Number of I/O 27
Core Processor AVR
Package / Case 32-VFQFN Exposed Pad
Data Converters A/D 8x10b
Oscillator Type Internal
Program Memory Size 32KB (16K x 16)
Program Memory Type FLASH
Operating Temperature -40degC ~ 85degC (TA)
Supplier Device Package 32-VFQFN (5x5)
Voltage - Supply (Vcc/Vdd) 1.8V ~ 5.5V

Getting Started

Engineers typically begin development using the Arduino Uno Rev3 for prototyping or the Atmel-ICE for hardware debugging. The toolchain is supported by Microchip Studio (formerly Atmel Studio) and the AVR-GCC compiler, allowing for both high-level C++ and optimized assembly development.

ATMEGA328P Family

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

Part Number I/O Pins Stock
ATmega328P (this part) 27 13,074
ATMEGA328P-MU 23 5,629
Also available as: ATMEGA328P-AUR, ATMEGA328P-PU, ATMEGA328P-AU

Also Consider

ATmega328PB MCHPMicrochip Technology - An enhanced version of the 328P offering additional timers, a second USART, and a second SPI/I2C interface in the same 32-pin package.
ATSAMD21G18A MCHPMicrochip Technology - A 32-bit ARM Cortex-M0+ alternative for applications requiring more RAM (32KB), native USB support, and higher processing performance.
ATtiny85 MCHPMicrochip Technology - A smaller 8-pin AVR microcontroller for extremely simple logic tasks that do not require the high pin count of the ATmega328P.

Categories

Microcontrollers > AVR Education & Prototyping > Arduino Ecosystem
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