ATMEGA328P-AN Microchip Technology

The ATMEGA328P-AN from Microchip Technology is a high-performance, low-power 8-bit AVR microcontroller based on the advanced RISC architecture. This model, housed in a compact 32-pin TQFP package, features 32KB of in-system self-programmable Flash memory, 2KB SRAM, and 1KB EEPROM. Operating from 1.8V to 5.5V, it integrates a rich set of peripherals including 8-channel 10-bit ADC, two 8-bit and one 16-bit timer/counter, two SPI interfaces, one I2C interface, and six PWM channels. Its combination of processing capability, versatile I/O, and low-power operation makes it an ideal embedded control solution for applications ranging from industrial automation and consumer electronics to IoT sensor nodes and DIY projects.

Key Features

• High Integration: Combines 32KB Flash, 2KB SRAM, 1KB EEPROM, 10-bit ADC, timers, and multiple communication interfaces (2xSPI, I2C) in a single chip.
• Wide Operating Voltage: Supports 1.8V to 5.5V, enabling design flexibility for both battery-powered and line-powered systems.
• Advanced Peripheral Set: Features six standalone PWM outputs, eight ADC channels, and multiple timers for precise motor control and signal measurement.
• Low Power Operation: Designed for power-sensitive applications, offering multiple sleep modes to minimize current consumption.

Technical Specifications

• Core Processor: 8-bit AVR
• Program Memory Size: 32 KB
• RAM Size: 2 KB
• EEPROM Size: 1 KB
• Digital I/O Pins: 23
• ADC Resolution / Channels: 10-bit / 8 channels
• Timer Count: 2 x 8-bit, 1 x 16-bit
• Communication Interfaces: 2 x SPI, 1 x I2C
• PWM Channels: 6
• Analog Comparators: 1
• Operating Voltage Range: 1.8V - 5.5V

Pin Configuration and Functions

• Pin1 (PC6/RESET): Reset input or digital I/O.
• Pin2 (PD0/RXD): USART Receive or digital I/O.
• Pin3 (PD1/TXD): USART Transmit or digital I/O.
• Pin4 (PD2/INT0): External Interrupt 0 or digital I/O.
• Pin5 (PD3/INT1/OC2B): External Interrupt 1 / PWM Output B or digital I/O.
• Pin6 (PD4/T0/XCK): Timer0 Clock Input or digital I/O.
• Pin7 (VCC): Supply Voltage.
• Pin8 (GND): Ground.
• Pin9 (PB6/TOSC1): Timer Oscillator Pin 1 or digital I/O.
• Pin10 (PB7/TOSC2): Timer Oscillator Pin 2 or digital I/O.
• Pin11 (PD5/T1/OC0B): Timer1 Input / PWM Output or digital I/O.
• Pin12 (PD6/AIN0/OC0A): Analog Comparator Input / PWM Output or digital I/O.
• Pin13 (PD7/AIN1): Analog Comparator Input or digital I/O.
• Pin14 (PB0/ICP1/CLKO): Input Capture / Clock Output or digital I/O.
• Pin15-22 (PB1-PB5, PC0-PC2): Digital I/O, ADC inputs (PC0-P2), SPI, PWM.
• Pin23 (PC3/ADC3): ADC Input or digital I/O.
• Pin24 (PC4/ADC4/SDA): ADC Input / I2C Data or digital I/O.
• Pin25 (PC5/ADC5/SCL): ADC Input / I2C Clock or digital I/O.
• Pin26 (ADC6): ADC Input (ADC6).
• Pin27 (ADC7): ADC Input (ADC7).
• Pin28 (AVCC): Supply Voltage for ADC.
• Pin29 (GND): Ground.
• Pin30 (AREF): ADC Reference Voltage.
• Pin31 (PB5/SCK): SPI Clock or digital I/O.
• Pin32 (PB4/MISO): SPI Master In Slave Out or digital I/O.

Typical Applications

• Industrial Control Systems: Embedded logic control, sensor data acquisition, and actuator drive.
• Consumer Electronics: Smart home devices, interactive toys, and appliance control panels.
• IoT and Sensor Nodes: Low-power remote sensors with data processing and communication.
• Prototyping and DIY: Arduino-compatible project core for education and rapid prototyping.

Equivalent / Alternative Parts

• ATMEGA328P-AU (Microchip): Identical specifications in a VQFP-32 package, offering a different physical footprint.
• ATMEGA328PB-AN (Microchip): Enhanced version with additional peripherals (extra SPI, I2C) while maintaining pin compatibility.

Advantages

• Balanced Memory Configuration: The 32KB Flash + 2KB SRAM + 1KB EEPROM offers an optimal balance for complex control logic, data variables, and parameter storage in mid-range applications.
• Versatile Power Management: The wide 1.8V-5.5V operating range allows direct use with various power sources, from coin cells to USB, simplifying power supply design.
• Rich I/O and Peripheral Mix: Provides ample digital I/O, ADC channels, and communication buses, reducing the need for external expansion ICs and minimizing system BOM cost.

Limitations

• Limited RAM Capacity: With only 2KB of SRAM, it is not suitable for applications requiring large data buffers or complex data structures.
• No Advanced Communication: Lacks built-in high-speed interfaces like USB or Ethernet, requiring external transceivers for such connectivity.
• 8-bit Architecture: The computational throughput is limited compared to 32-bit MCUs, making it less ideal for heavy digital signal processing or high-speed control loops.

Package Information

TQFP-32 package (7x7mm body size), 32 pins, surface mount type with a lead pitch of 0.8mm.

Manufacturer Information

Microchip Technology Inc. is a leading provider of microcontroller, mixed-signal, analog, and Flash-IP solutions. Known for its robust and reliable product portfolio, Microchip offers comprehensive development tools and technical support for its embedded control systems, serving a wide range of markets from industrial and automotive to consumer and computing.

Design-in Tips

• Decouple Power Pins: Place 100nF and optionally a 10µF capacitor as close as possible to the VCC/AVCC and GND pins to ensure stable operation and reduce noise, especially when using the ADC.
• Manage Unused Pins: Configure unused I/O pins as outputs driving low or inputs with an internal pull-up enabled to prevent floating inputs and reduce power consumption.
• ADC Reference Stability: For accurate analog-to-digital conversion, use a stable, low-noise voltage reference on the AREF pin and ensure the analog ground is properly separated from digital noise.

Lifecycle Status & PCN/PDN Notes

Lifecycle status information is not provided in the input parameters. No Product Change Notification (PCN) or Product Discontinuation Notification (PDN) information is available for this specific entry.