ATMEGA328P-MU - 8-bit AVR MCU 20MHz 32KB Flash VQFN-32
料号： ATMEGA328P-MU ✗ 停产| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $4.2 | $4.20 |
| 10 | $3.85 | $38.50 |
| 100 | $3.45 | $345.00 |
| 500 | $3.1 | $1,550.00 |
| 1,000 | $2.85 | $2,850.00 |
ATMEGA328P-MU 概述
An 8-bit microcontroller (MCU) is a single-chip computing subsystem that combines a CPU core, non-volatile program memory (Flash), volatile data memory (SRAM), non-volatile data storage (EEPROM), and a rich set of peripherals such as timers, ADC, and communication interfaces. MCUs sit at the heart of embedded systems, bridging the gap between simple logic ICs and application processors in the broader semiconductor hierarchy, and are typically deployed where deterministic real-time control, low power, and cost efficiency are paramount.
Key features of the ATMEGA328P-MU include 131 single-cycle RISC instructions, picoPower technology with multiple sleep modes for battery-powered systems, two 8-bit timers plus one 16-bit timer, a master/slave SPI interface, an I2C-compatible TWI, and a programmable USART. The P-suffix denotes the picoPower variant, with internal 8 MHz and 128 kHz calibrated RC oscillators that minimize external component count. On-chip debug is supported via debugWIRE and In-System Programming (ISP) enables field firmware upgrades without desoldering.
Architecturally, the ATmega328P uses an AVR Harvard-architecture RISC core with 32 general-purpose working registers directly connected to the ALU, allowing two independent registers to be accessed in a single instruction executed in one clock cycle. The QFN-32 (5x5 mm) package exposes two extra ADC inputs (ADC6, ADC7) compared to the PDIP-28, and provides a low thermal resistance path through the exposed pad for improved heat dissipation at 20 MHz / 5 V operation.
Typical applications include Arduino-compatible boards (Uno, Nano, Pro Mini), industrial sensor nodes, consumer appliances, hobby robotics, battery-powered instrumentation, and LED lighting controllers. Its 1.8 V to 5.5 V operating range supports both 3.3 V and 5 V rails, and the rich timer set enables precise PWM motor control and switching-mode LED dimming.
When designing with this device, place a 100 nF decoupling capacitor on each AVCC and VCC pin, keep the analog reference (AREF) quiet with its own bypass capacitor, and ensure the exposed thermal pad is soldered to a ground copper pour to meet the datasheet's 31 C/W theta-JA thermal budget.
This page synthesizes distributor pricing, drop-in alternatives, pinout data, and practical design notes not found in a single manufacturer datasheet, as of 2026-10-07.
直接替换替代料： ATMEGA328P-MU ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： ATMEGA328P-MU （相同外形与封装尺寸） ——差异在于 Package, Operating Temperature, Communication Interfaces, Timers, ADC.
快速对比工具——选择替代料号进行并排对比：
ATMEGA328PB-MU
✅ 直接替换✓ 有现货
$1.19 / 个
查看数据手册 →ATMEGA328P-AU
✅ 直接替换✓ 有现货
$1.74 / 个
查看数据手册 →ATMEGA328P-MUR
✅ 直接替换📋 参考替代料（不在目录中）
ATMEGA168PA-MU
✅ 直接替换✓ 有现货
$1.72 / 个
查看数据手册 →ATMEGA88PA-MU
✅ 直接替换✓ 有现货
$1.26 / 个
查看数据手册 →ATMEGA48PA-MU
✅ 直接替换✓ 有现货
$1.08 / 个
查看数据手册 →ATMEGA328P-AUR
✅ 直接替换✓ 有现货
$2.18 / 个
查看数据手册 →ATMEGA328P-MU 最大额定值与电气特性
| Core Architecture | AVR 8-bit RISC |
| Maximum Clock Speed | 20 MHz |
| Instruction Throughput | 20 MIPS |
| Flash Program Memory | 32 KB (16 K x 16) |
| SRAM | 2 KB |
| EEPROM | 1 KB |
| Operating Voltage Range | 1.8 V to 5.5 V |
| General-Purpose I/O | 23 lines |
| ADC | 10-bit, 8 channels (6 + 2 dedicated QFN/VFP) |
| Timers/Counters | 2 x 8-bit, 1 x 16-bit |
| Communication Interfaces | USART, SPI (master/slave), TWI (I2C-compatible) |
| On-chip Oscillator | Internal 8 MHz calibrated, 128 kHz |
| 封装 | 32-pin VQFN (5x5 mm, exposed pad) |
| 安装类型 | Surface Mount |
| 工作温度 | -40 C to +85 C (industrial) |
| Programming Interface | ISP, debugWIRE, TPI |
| RoHS 状态 | Compliant |
ATMEGA328P-MU 引脚配置
| 引脚 1 | PD3 — Digital I/O, INT1, OC2B, PCINT19 |
| 引脚 2 | PD4 — Digital I/O, T0, XCK1, PCINT20 |
| 引脚 3 | GND — Ground (common with exposed pad) |
| 引脚 4 | VCC — Digital supply voltage |
| 引脚 5 | GND — Ground |
| 引脚 6 | VCC — Digital supply voltage |
| 引脚 7 | PB6 — Digital I/O, XTAL1, PCINT6 |
| 引脚 8 | PB7 — Digital I/O, XTAL2, PCINT7 |
| 引脚 9 | PD5 — Digital I/O, OC0B, T1, PCINT21 |
| 引脚 10 | PD6 — Digital I/O, OC0A, AIN0, PCINT22 |
| 引脚 11 | PD7 — Digital I/O, OC1A, AIN1, PCINT23 |
| 引脚 12 | PB0 — Digital I/O, ICP1, PCINT0 |
| 引脚 13 | PB1 — Digital I/O, OC1A, CLKO, PCINT1 |
| 引脚 14 | PB2 — Digital I/O, SS, OC1B, PCINT2 |
| 引脚 15 | PB3 — Digital I/O, MOSI, OC2A, PCINT3 |
| 引脚 16 | PB4 — Digital I/O, MISO, PCINT4 |
| 引脚 17 | PB5 — Digital I/O, SCK, PCINT5 |
| 引脚 18 | AVCC — Analog supply voltage |
| 引脚 19 | ADC6 — Analog input 6 (QFN dedicated) |
| 引脚 20 | AREF — ADC reference voltage |
| 引脚 21 | GND — Ground |
| 引脚 22 | ADC7 — Analog input 7 (QFN dedicated) |
| 引脚 23 | PC0 — Digital I/O, ADC0, PCINT8 |
| 引脚 24 | PC1 — Digital I/O, ADC1, PCINT9 |
| 引脚 25 | PC2 — Digital I/O, ADC2, PCINT10 |
| 引脚 26 | PC3 — Digital I/O, ADC3, PCINT11 |
| 引脚 27 | PC4 — Digital I/O, ADC4, SDA, PCINT12 |
| 引脚 28 | PC5 — Digital I/O, ADC5, SCL, PCINT13 |
| 引脚 29 | RESET — Reset, active low |
| 引脚 30 | PD0 — Digital I/O, RXD, PCINT16 |
| 引脚 31 | PD1 — Digital I/O, TXD, PCINT17 |
| 引脚 32 | PD2 — Digital I/O, INT0, PCINT18 |
典型应用
ATMEGA328P-MU 适用于 6 应用s: Arduino-Compatible Development Boards, Industrial Sensor Nodes, Consumer Appliance Controllers, Battery-Powered Instrumentation, Hobby Robotics and RC Vehicles, LED Lighting Controllers.
Arduino-Compatible Development Boards
The ATMEGA328P-MU powers hundreds of Arduino-compatible boards (Uno, Nano, Pro Mini) where its 32 KB Flash accommodates the Optiboot bootloader plus typical sketches, and 2 KB SRAM supports library-rich code. The VQFN-32 (5x5 mm) footprint enables compact Nano-class designs while exposing 23 GPIO for shields. Developers benefit from Arduino IDE support and a vast library ecosystem, accelerating prototyping and education.
推荐
Industrial Sensor Nodes
The ATMEGA328P-MU fits battery-powered industrial sensor nodes because its picoPower architecture offers six sleep modes drawing under 1 uA in power-down, and the 10-bit ADC with 8 channels handles multiple sensors simultaneously. The 1.8 V to 5.5 V range supports direct Li-ion or 3.3 V coin-cell operation, while the I2C/TWI and SPI buses interface with modern digital sensors. Typical use: remote environmental monitoring, predictive maintenance tags, and wireless mesh nodes.
推荐
Consumer Appliance Controllers
Consumer appliances such as coffee machines, microwaves, and washing-machine control boards rely on the ATMEGA328P-MU's 23 GPIO to drive keypads, relays, displays, and sensors. Its 32 KB Flash fits feature sets including user-interface state logic, while the 16-bit timer supports precise timing for any sensor-driven control loops. The wide 1.8 V to 5.5 V input tolerates rectified mains supplies with linear regulation.
推荐
Battery-Powered Instrumentation
Battery-powered instruments such as handheld multimeters, dataloggers, and portable medical devices leverage the ATMEGA328P-MU's picoPower modes to extend runtime from a single Li-ion or AA cell. The internal 8 MHz RC oscillator eliminates an external crystal, reducing BOM cost and board area, while the 128 kHz watchdog allows ultra-low-power sleep between measurements. The 10-bit ADC supports sensor signal conditioning with software averaging.
推荐
Hobby Robotics and RC Vehicles
Robotics projects use the ATMEGA328P-MU to drive servos, ESCs, and DC motor controllers via PWM channels on the 16-bit timer, plus the two 8-bit timers for additional PWM outputs. The 23 GPIO supports multiple motor drivers, encoder inputs, and UART/SPI buses for IMU and radio modules. At 20 MHz / 20 MIPS, control loops run at comfortable 1 ms intervals without CPU loading.
推荐
LED Lighting Controllers
LED controllers benefit from the ATMEGA328P-MU's PWM channels for smooth RGB dimming and the 10-bit ADC for ambient-light feedback. The I2C/TWI bus interfaces with WS2812 or APA102 LED drivers, while the USART links to DMX or wireless modules for stage lighting and architectural installations. The wide operating range supports both 3.3 V and 5 V LED strips from a single design.
推荐
推荐产品汇总
工程参考数据： ATMEGA328P-MU ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | ATMEGA328PB-MU | ATMEGA328P-AU | ATMEGA328P-MUR | ATMEGA168PA-MU | ATMEGA88PA-MU | ATMEGA48PA-MU | ATMEGA328P-AUR |
|---|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | VQFN-32 (5x5 mm) | VQFN-32 (5x5 mm) - same | TQFP-32 (7x7 mm) - same pinout | 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 |
| Flash Memory | 32 KB | 32 KB | 32 KB | 32 KB | 16 KB (-50%) | 8 KB (-75%) | 4 KB (-87%) | 32 KB |
| SRAM | 2 KB | 2 KB | 1 KB (-50%) | 1 KB (-50%) | 512 B (-75%) | |||
| EEPROM | 1 KB | 1 KB | 512 B | 512 B | 256 B | |||
| Maximum Clock Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | ||
| Operating Voltage Range | 1.8 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 | 1.8 V to 5.5 V | |||
| Additional Peripherals vs Original | Standard | +2nd USART, +2nd I2C, +10-bit DAC, +more PWM | Identical to MU | Reduced memory, identical peripherals | ||||
| Lifecycle Status | NRND | Active (recommended for new designs) | NRND | Active |
关键差异点
- Drop-in upgrade available with 2nd USART/I2C and 10-bit DAC （对比 ATMEGA328PB-MU)
- TQFP variant exists for hand-soldering （对比 ATMEGA328P-AU)
- Two extra ADC inputs vs PDIP-28 （对比 ATMEGA328P-PU (DIP-28))
设计说明
Decouple each ATMEGA328P-MU VCC/AVCC pin with a 100 nF ceramic capacitor placed within 3 mm of the pin, plus a bulk 10 uF aluminum-polymer or tantalum capacitor on the supply rail. For ADC accuracy, place a 10 nF + 100 nF capacitor network on AREF with the AVCC filter inductor (10 uH typical) to suppress digital switching noise coupling into analog measurements.
The ATMEGA328P-MU VQFN-32 has a theta-JA of approximately 31 C/W (per Microchip datasheet thermal data), so at full 20 MHz / 5 V operation the junction-to-ambient rise is around 7-8 C per 100 mA active current. Always solder the exposed thermal pad to a ground copper pour of at least 1 square inch to meet the thermal envelope under continuous worst-case operation.
Route the analog traces (ADC inputs, AREF, AVCC) away from digital switching lines; keep ground return paths short and use a star-ground topology with the MCU exposed pad as the single-point ground tie. Place the I2C pull-ups (typically 4.7 kohm) close to the SDA/SCL pins to reduce rise-time ringing on the bus.
Do not assume ATMEGA328P and ATMEGA328PB registers are identical at the silicon level — the 328PB adds new registers (e.g., second USART/UCSR1) and pin maps that require updated headers. If migrating firmware, verify AVR-libc version and compile-time MCU flags. Also note that ATmega328P runs at 10 MHz max below 2.7 V, not 20 MHz, so derate clock for low-voltage battery designs.
合规信息
RoHS compliant per Microchip product page. Not AEC-Q100 qualified for automotive — refer to Microchip automotive AVR catalog for Q-qualified variants. NRND status as of 2026-10-07; recommend ATmega328PB for new designs.
