ATMEGA328P-MNR - AVR 8-bit MCU 20MHz 32KB Flash 32-VQFN | Microchip (Tape & Reel)
MPN： ATMEGA328P-MNR ✓ 啟用中ATMEGA328P-MNR 概覽
A microcontroller (MCU) is a single-chip computer that integrates a CPU, memory (Flash for program, SRAM for data, EEPROM for non-volatile storage), and programmable peripherals on one die. The ATmega328P belongs to the AVR enhanced RISC architecture family, which executes most instructions in a single clock cycle, enabling deterministic timing essential for real-time embedded control. Within the broader taxonomy, the ATmega328P-MN is a microcontroller -> embedded processor -> semiconductor device, and is the canonical MCU used on Arduino Uno and Arduino Nano carrier boards.
Key features include 131 RISC instructions, a debugWIRE on-chip debug interface, six PWM channels, a 10-bit ADC, programmable watchdog timer with separate on-chip oscillator, and five software-selectable power-saving modes that drop quiescent current below 1 µA in power-down mode. Internal 8 MHz and 128 kHz RC oscillators reduce external component count for cost-sensitive designs.
The device is built on a low-power CMOS process with an advanced Harvard architecture that separates program and data buses for simultaneous fetch and write, achieving throughput up to 20 MIPS at 20 MHz. Hardware multipliers and true single-cycle execution make it well suited to deterministic control loops in sensor processing and communication bridging.
Typical applications include Arduino-compatible maker boards, consumer appliance controllers, sensor data acquisition nodes, battery-powered IoT endpoints, industrial 4-20 mA loop interfaces, and hobby/educational platforms. Designers choose the ATmega328P-MN for its mature toolchain (avr-gcc, Arduino IDE, Atmel Studio), abundant reference designs, and the broad availability of code libraries.
Design tip: When migrating from the plastic DIP-28 (ATMEGA328P-PU) footprint used on the classic Arduino Uno to the QFN-32 package, ensure your PCB includes a thermal pad with at least 6 ground vias to dissipate the package's heat under high CPU load, and use a 0.5 mm pitch land pattern that respects the JEDEC MSL3 moisture sensitivity.
This page synthesizes live distributor pricing, drop-in VQFN-32 alternatives (ATMEGA328PB-MN, ATMEGA328-MN, ATMEGA168P-MN), and engineering guidance not aggregated on a single OEM datasheet page.
直接替換替代品，適用於 ATMEGA328P-MNR — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： ATMEGA328P-MNR （相同外形與佔位） — 差異在於 Operating Temperature, Package, SRAM, Core Architecture, EEPROM.
ATMEGA328PB-MN
✅ 直接替換📋 參考替代品（不在目錄中）
ATMEGA328-MN
✅ 直接替換📋 參考替代品（不在目錄中）
ATMEGA168P-MN
✅ 直接替換📋 參考替代品（不在目錄中）
ATMEGA88P-MN
✅ 直接替換📋 參考替代品（不在目錄中）
ATMEGA48P-MN
✅ 直接替換📋 參考替代品（不在目錄中）
ATMEGA328P-MNR 最大額定值與電氣特性
| Core Architecture | AVR 8-bit RISC |
| Program Memory (Flash) | 32 KB (16K x 16) |
| SRAM | 2 KB |
| EEPROM | 1 KB |
| Maximum CPU Speed | 20 MHz |
| 供應電壓 | 1.8 V to 5.5 V |
| Throughput | Up to 20 MIPS at 20 MHz |
| Programmable I/O Lines | 23 |
| ADC | 6 channels, 10-bit |
| Timers | 2x 8-bit, 1x 16-bit |
| PWM Channels | 6 |
| Communication Interfaces | 1x USART, 1x SPI, 1x TWI (I2C) |
| 工作溫度 | -40 °C to +105 °C |
| 封裝 | 32-pin VQFN (5x5 mm) |
| 安裝類型 | Surface Mount |
| RoHS 狀態 | Compliant |
| Debug Interface | debugWIRE |
ATMEGA328P-MNR 腳位配置
| 腳位 1 | PD3 (OC2B, INT1) — PORTD bit 3, Timer/Counter2 compare B, external interrupt 1 |
| 腳位 2 | PD4 (T0, XCK) — PORTD bit 4, Timer0 external clock, USART0 clock |
| 腳位 3 | GND — Digital ground |
| 腳位 4 | VCC — Digital supply voltage |
| 腳位 5 | GND — Digital ground |
| 腳位 6 | VCC — Digital supply voltage |
| 腳位 7 | PD5 (OC0B, T1) — PORTD bit 5, Timer0 compare B, Timer1 external clock |
| 腳位 8 | PD6 (OC0A, AIN0) — PORTD bit 6, Timer0 compare A, analog comparator +input |
| 腳位 9 | PD7 (OC2A, AIN1) — PORTD bit 7, Timer2 compare A, analog comparator -input |
| 腳位 10 | PB0 (ICP1, CLKO) — PORTB bit 0, Timer1 input capture, system clock output |
| 腳位 11 | PB1 (OC1A) — PORTB bit 1, Timer1 compare A |
| 腳位 12 | PB2 (OC1B, SS) — PORTB bit 2, Timer1 compare B, SPI slave select |
| 腳位 13 | PB3 (MOSI, OC2A) — PORTB bit 3, SPI MOSI, Timer2 compare A |
| 腳位 14 | PB4 (MISO) — PORTB bit 4, SPI MISO |
| 腳位 15 | PB5 (SCK) — PORTB bit 5, SPI clock |
| 腳位 16 | PB6 (XTAL1, TOSC1) — PORTB bit 6, crystal oscillator pin 1, Timer2 oscillator pin 1 |
| 腳位 17 | PB7 (XTAL2, TOSC2) — PORTB bit 7, crystal oscillator pin 2, Timer2 oscillator pin 2 |
| 腳位 18 | AREF — ADC reference voltage input |
| 腳位 19 | GND — Digital ground |
| 腳位 20 | AVCC — Analog supply voltage |
| 腳位 21 | ADC7 — ADC channel 7 |
| 腳位 22 | ADC6 — ADC channel 6 |
| 腳位 23 | PC0 (ADC0) — PORTC bit 0, ADC channel 0 |
| 腳位 24 | PC1 (ADC1) — PORTC bit 1, ADC channel 1 |
| 腳位 25 | PC2 (ADC2) — PORTC bit 2, ADC channel 2 |
| 腳位 26 | PC3 (ADC3) — PORTC bit 3, ADC channel 3 |
| 腳位 27 | PC4 (SDA) — PORTC bit 4, I2C data |
| 腳位 28 | PC5 (SCL) — PORTC bit 5, I2C clock |
| 腳位 29 | PC6 (RESET) — PORTC bit 6, reset (active low) |
| 腳位 30 | PD0 (RXD) — PORTD bit 0, USART0 RX |
| 腳位 31 | PD1 (TXD) — PORTD bit 1, USART0 TX |
| 腳位 32 | PD2 (INT0) — PORTD bit 2, external interrupt 0 |
| 腳位 33 | EP — Exposed thermal pad (must be soldered to ground for thermal performance) |
典型應用
ATMEGA328P-MNR 適用於 6 應用s: Arduino-Compatible Maker Boards, Battery-Powered IoT Sensor Nodes, Industrial 4-20 mA Loop Transmitters, Consumer Appliance Control Boards, Educational and STEM Platforms, Hobby Robotics and Servo Control.
Arduino-Compatible Maker Boards
The ATMEGA328P-MNR is the surface-mount VQFN-32 die behind most Arduino-compatible boards, including the Arduino Nano and the SMD variants of the Uno. Its 20 MHz AVR core and 32 KB Flash run the Arduino boot loader and the full avr-gcc library set unmodified, while 23 programmable I/O lines expose PWM, ADC, and I2C/SPI for shields and breakout boards. The 105 °C operating range and 1.8 V–5.5 V supply tolerance let the same part serve 3.3 V Feather-class boards and legacy 5 V boards without redesign.
推薦
Battery-Powered IoT Sensor Nodes
The ATMEGA328P-MNR's five software-selectable power-saving modes (Idle, ADC Noise Reduction, Power-save, Power-down, Standby) drop quiescent current below 1 µA in power-down mode while retaining the ability to wake on watchdog, external interrupt, or pin change. With 1.8 V operation it runs directly from a single Li-FePO4 cell, and its 32 KB Flash accommodates Over-the-Air update code for LoRaWAN or Zigbee stack bring-up. Real-world designs typically see 3–5 year battery life on a 2400 mAh cell when the MCU sleeps between sensor reads.
推薦
Industrial 4-20 mA Loop Transmitters
The ATMEGA328P-MNR's 10-bit ADC with six channels and 1.8 V–5.5 V analog supply range matches the signal levels from 4-20 mA current loops and bridge sensors. Its hardware TWI (I2C) and SPI peripherals drive external DACs and digital isolators, while the watchdog timer and brown-out detector provide the supervisory functions demanded by industrial process-control standards. –40 °C to +105 °C operation handles the typical industrial enclosure temperature range without derating.
推薦
Consumer Appliance Control Boards
In washing machines, coffee makers, and HVAC zone controllers, the ATMEGA328P-MNR's six PWM channels drive TRIACs, MOSFETs, and variable-frequency drives, while its USART interfaces to main-display or Wi-Fi modules. The 32 KB Flash supports capacitive-touch firmware and safety-state machines, and the –40 °C to +105 °C rating meets appliance under-hood thermal stress. Combined with its sub-$3 reel price, it offers the best MCU price/performance for high-volume consumer SKUs shipping in the millions of units per year.
推薦
Educational and STEM Platforms
The ATMEGA328P-MNR is the de-facto learning MCU in universities and maker spaces because the avr-gcc, Arduino IDE, and Microchip Studio all target it as a first-class citizen. Its 32 KB Flash holds the standard Arduino boot loader plus user sketches, and the debugWIRE interface supports single-pin in-circuit debugging from low-cost tools such as the Atmel-ICE and the AVR Dragon. Students benefit from deterministic single-cycle instruction execution, which makes timing tutorials and assembly primer labs reproducible on every board revision.
推薦
Hobby Robotics and Servo Control
Robotics hobbyists rely on the ATMEGA328P-MNR to drive multi-servo gimbals, BLDC ESC interfaces, and sensor fusion loops at the heart of hexapods, robotic arms, and pan-tilt gimbals. The 16-bit Timer/Counter1 supports high-precision PWM in the 50 Hz servo range, and the six PWM outputs cover typical 4–6 servo limbs without external drivers. The 32 KB Flash accommodates inverse-kinematics libraries and IMU fusion filters; the I2C bus ties in MPU6050 / BNO055 IMUs directly without glue logic.
推薦
推薦產品摘要
工程參考資料，適用於 ATMEGA328P-MNR — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | ATMEGA328PB-MN | ATMEGA328-MN | ATMEGA168P-MN | ATMEGA88P-MN | ATMEGA48P-MN |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | VQFN-32 (5x5 mm) | VQFN-32 (5x5 mm) - same | VQFN-32 (5x5 mm) - same | VQFN-32 (5x5 mm) - same | VQFN-32 (5x5 mm) - same | VQFN-32 (5x5 mm) - same |
| Program Memory (Flash) | 32 KB | 32 KB | 32 KB | 16 KB | 8 KB | 4 KB |
| SRAM | 2 KB | 2 KB | 2 KB | 1 KB | 1 KB | 512 B |
| EEPROM | 1 KB | 1 KB | 1 KB | 512 B | 256 B | 256 B |
| Max CPU Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Supply Voltage | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 4.5 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| PWM Channels | 6 | 9 (+3 vs base) | 6 | 6 | 6 | 6 |
| USART / SPI / TWI | 1 / 1 / 1 | 2 / 2 / 1 (+1 USART, +1 SPI) | 1 / 1 / 1 | 1 / 1 / 1 | 1 / 1 / 1 | 1 / 1 / 1 |
主要差異化特點
- Highest Flash density in the VQFN-32 8-bit AVR family (對比ATMEGA168P-MN)
- Backwards-compatible peripheral upgrade path (對比ATMEGA328PB-MN)
- PicoPower (P-variant) low-voltage operation (對比ATMEGA328-MN)
- Mature, broadest ecosystem and code-library compatibility (對比ATMEGA88P-MN)
設計說明
The 32-pin VQFN package requires that the exposed thermal pad (pin 33) be soldered directly to a ground copper pour with at least six thermal vias (0.3 mm drill, 0.6 mm pads) stitching to inner ground planes. At 20 MHz with all peripherals running, the die dissipates roughly 30 mW; without a thermal pad the junction-to-ambient thermal resistance can climb above 70 C/W, violating the 105 °C ceiling in enclosed housings. Use at least 1 oz copper on the top layer beneath the device for best thermal relief.
Place the 0.1 µF VCC decoupling capacitor within 2 mm of pin 4 (and pin 20 AVCC), with a 10 µF bulk capacitor on the same rail no more than 20 mm away. Route the crystal traces (PB6/XTAL1, PB7/XTAL2) as short, ground-guarded differential pairs under 10 mm, and add 22 pF load capacitors to GND within 3 mm of each pin. Avoid routing high-speed SPI or USART lines across the crystal region to prevent jitter and EMI.
Estimated: when migrating from ATMEGA328P-PU (DIP-28) to -MN (VQFN-32), the ADC channels 6 and 7 are mapped to dedicated analog-only pins (no digital function) and C6 lacks RESET functionality, requiring a 10 kΩ pull-up to VCC and the fuse set to disable RESET (RSTDISBL programmed). Designers commonly forget that an unprogrammed -PU will draw 5 mA continuously because the internal pull-up on the RESET pin keeps the chip in reset without a clean high level.
Activate the Brown-out Detector (BOD) fuse at 2.7 V threshold for all battery-powered designs to guarantee predictable reset behavior below the safe operating range. In power-down mode the ATMEGA328P-MNR draws less than 1 µA with the watchdog disabled; enabling the watchdog adds roughly 4 µA. Wake sources can be WDT, INT0/INT1 external interrupts, or pin-change interrupts on PORTB — disable unused analog comparators and the ADC (PRR register) to reach the bottom of the datasheet's power curve.
合規資訊
RoHS and REACH compliant per the Microchip material declaration page. Not AEC-Q100 qualified: for automotive safety-critical applications use an AEC-Q100 grade part such as the PIC18F46K22-I/PT or ATSAM series. Lead-free VQFN-32 package is MSL3 rated; observe JEDEC J-STD-033 moisture bake procedures before reflow.
