ATMEGA328-PU Microchip 8 Bit Microcontroller DIP-28

ATMEGA328-PU Microchip 8 Bit Microcontroller DIP-28 is the highly popular, high-performance, low-power AVR microcontroller featuring the robust RISC architecture developed by Microchip (formerly Atmel). This specific part comes in the through-hole, DIP-28 package (PU), making it exceptionally easy to prototype and integrate into breadboards and custom PCBs. Consequently, the ATMEGA328-PU remains a foundational component for countless hobbyist projects and commercial embedded systems worldwide, primarily serving as the core processor of the ubiquitous Arduino Uno and Pro Mini platforms. Furthermore, its combination of 32 KB Flash memory, powerful instruction set, and ample peripheral integration delivers an excellent balance of capability and cost-effectiveness for developers.

Key Features:

• High-Performance AVR RISC CPU: Executes powerful instructions in a single clock cycle, achieving throughputs approaching 1 MIPS per MHz, optimizing both power consumption and processing speed.
• 32KB Flash Memory: Offers substantial program storage, allowing for complex sketches and integrated software libraries.
• Robust Memory Architecture: Features 2 KB of SRAM for dynamic data and 1 KB of EEPROM for non-volatile configuration storage.
• Rich Peripheral Set: Includes multiple timers/counters, 6-channel 10-bit ADC, USART, SPI, and I²C (Two-wire Serial Interface), offering wide flexibility for diverse applications.
• DIP-28 Package: The P (Plastic) U (Through-Hole) package simplifies prototyping and minimizes assembly complexity for small-to-medium volume production.

Technical Specifications:

• Architecture: 8-bit AVR RISC
• Maximum Clock Frequency: 20 MHz
• Flash Memory: 32 KB
• SRAM: 2 KB
• EEPROM: 1 KB
• I/O Pins: 23 programmable I/O lines
• ADC Channels: 6 channels (10-bit resolution)
• Operating Voltage (V_CC): 1.8 V to 5.5 V
• Operating Temperature Range: −40°C to +85°C (Industrial Grade)

Mechanical Specifications:

• Package Type: DIP-28 (Dual In-line Package)
• Mounting: Through-Hole Technology (THT)
• Pin Spacing (Pitch): 2.54 mm (0.1 inch)
• Row Spacing: 15.24 mm (0.6 inch)
• Material: Plastic Encapsulation

Dimensions:

• Body Length: ≈ 36.8 mm
• Body Width: ≈ 6.4 mm
• Overall Width (Pin Tip to Tip): 15.24 mm (Standard 0.6 inch DIP width)
• Weight: ≈ 2.5 g

Pinout and Wiring:

• VCC/GND: Connect VCC to the positive supply (typically 5V) and GND to ground.
• AVCC/AREF: AVCC powers the ADC, and AREF is the analog reference pin. Connect AVCC to VCC and bypass with a capacitor; connect AREF to VCC or an external reference.
• Port B (D8-D13): General purpose I/O pins, including the main SPI interface and Timer/Counter pins.
• Port C (A0-A5, RESET): Analog Input pins (A0-A5), I²C pins (A4/A5), and the critical RESET pin. Drive the RESET pin low to restart the chip.
• Port D (D0-D7): General purpose I/O pins, including the main USART (Serial) communication pins (RXD/TXD).
• XTAL1/XTAL2: Connect these pins to a crystal or ceramic resonator (e.g., 16 MHz) and appropriate load capacitors for external clocking.

Datasheet Reference:

• Download Microchip ATmega328P Datasheet

Commonly Used in:

• Arduino Boards: It is the primary MCU used in the Arduino Uno R3 and many Pro Mini variants.
• Hobbyist Electronics: Because of the vast online community and simple programming environment, hobbyists widely adopt this chip for learning and experimentation.
• Rapid Prototyping: The DIP package simplifies development, allowing engineers and students to quickly test circuits on breadboards.

Applications:

• Simple Automation: Controlling relays, lights, and small motors in home automation projects.
• Sensing and Measurement: Reading sensor data (temperature, humidity, distance) and processing information via the built-in ADC.
• Display Control: Driving LCDs, OLEDs, and seven-segment displays via SPI or I²C communication.
• Standalone Embedded Systems: Serving as the low-cost controller for custom electronic devices, timers, and small gadgets.

Equivalent Models:

• ATMEGA168-PU: A lower-memory variant (16 KB Flash) that shares the same pinout and architecture, however, it is suitable for simpler applications.
• ATMEGA328P-AU: The surface-mount technology (SMT) equivalent in a TQFP package, often used when space constraints require a smaller footprint.
• ATMEGA328PB: A newer iteration that includes extra peripherals (like an additional USART and I²C), often used when upgrading legacy designs.

Package Includes:

• 1 x ATMEGA328-PU Microchip 8 Bit Microcontroller DIP-28