ATMEGA324P-20MU - 8-bit AVR MCU 20MHz 32KB Flash | Microchip
料号： ATMEGA324P-20MU ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $5.27 | $5.27 |
| 10 | $4.8 | $48.00 |
| 100 | $4.35 | $435.00 |
| 500 | $4.05 | $2,025.00 |
| 1,000 | $3.8 | $3,800.00 |
ATMEGA324P-20MU 概述
An 8-bit AVR microcontroller is a single-chip computer that executes an advanced RISC instruction set, combining program Flash, data SRAM, EEPROM, timers, communication peripherals and general-purpose I/O in one package. Within the embedded hierarchy, the ATmega324P sits in the mid-range of the AVR ATmega family, positioned between smaller parts such as the ATmega168 and larger devices such as the ATmega644P, and is a classic member of the wider microcontroller unit (MCU) and power-management-of-systems product category.
Key features include 131 powerful instructions with mostly single-cycle execution, 32 general-purpose I/O lines, 1 KB EEPROM with read-while-write Flash capability, a real-time counter, and three flexible timers/counters with compare modes and PWM outputs. The device integrates two USARTs, a byte-oriented two-wire serial interface (I2C-compatible), an SPI serial port, a 10-bit ADC, and a programmable watchdog timer with an internal oscillator.
Technically, the picoPower technology enables very low power consumption in sleep modes, while the Harvard architecture with 32 general-purpose working registers achieves throughputs approaching 1 MIPS per MHz, letting designers trade clock speed directly against supply current. In-system programmability (ISP) via SPI allows firmware updates on the assembled board, and JTAG boundary-scan and on-chip debugging are supported through MPLAB tools such as the SNAP programmer.
Typical applications include industrial control panels, sensor nodes and instrumentation, consumer appliances, and motor-control or HVAC systems where a 5 V noise-immune MCU with rich peripherals is preferred over a 3.3 V part.
A key design consideration: at 20 MHz and 5 V operation, verify Brown-out Detection settings and decouple AVCC with an RC filter to preserve ADC accuracy. Pricing on this page is current as of 2026-09-17, and drop-in alternatives from the same ATmega family are listed below.
This page synthesizes distributor pricing, pin-compatible family alternatives, design notes and AI-optimized FAQs not found together on the manufacturer datasheet, giving engineers a complete sourcing and design reference in one place.
直接替换替代料： ATMEGA324P-20MU ——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： ATMEGA324P-20MU （相同外形与封装尺寸） ——差异在于 Package, Flash Memory, Operating Temperature, EEPROM, SRAM.
快速对比工具——选择替代料号进行并排对比：
ATMEGA324P-20MQ
✅ 直接替换✓ 有现货
$4.15 / 个
查看数据手册 →ATMEGA324PA-MU
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$2.05 / 个
查看数据手册 →ATMEGA324PB-MU
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$1.35 / 个
查看数据手册 →ATMEGA644P-20MU
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$5.02 / 个
查看数据手册 →ATMEGA164P-20MU
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$2.98 / 个
查看数据手册 →ATMEGA324P-20MU 最大额定值与电气特性
| Core Processor | AVR |
| Core Size | 8-Bit |
| Speed | 20 MHz |
| Flash Memory | 32 KB (16K x 16) |
| EEPROM | 1 KB |
| SRAM | 2 KB |
| Supply Voltage Range | 4.5 V to 5.5 V |
| General Purpose I/O | 32 |
| Timers/Counters | 3 (with compare modes and PWM) |
| USART | 2 |
| ADC Resolution | 10-bit |
| Connectivity | I2C (TWI), SPI, UART/USART |
| 封装 | 44-VQFN (7x7 mm), exposed pad |
| 安装类型 | Surface Mount |
| 工作温度 | -40C to +85C |
| Programmer Support | MPLAB SNAP (ICSP, in-circuit debug) |
| Technology | picoPower, AVR RISC, 131 instructions |
ATMEGA324P-20MU 44-vqfn (7x7 mm), exposed pad 引脚配置指南
ATMEGA324P-20MU（44-vqfn (7x7 mm), exposed pad 封装）的引脚配置。 该数字 IC 包含 GPIO、通信接口（UART、SPI、I2C）和电源引脚。请参阅制造商数据手册以了解复用引脚功能和配置选项。对嵌入式系统设计和 PCB 布局至关重要。
暂无详细引脚数据： ATMEGA324P-20MU.
请参阅 数据手册 以查看完整引脚配置。
典型应用
ATMEGA324P-20MU 适用于 6 应用s: Industrial Control and Automation, Sensor Acquisition Nodes, Motor Control and HVAC Systems, Consumer Appliances, Instrumentation and Test Equipment, Embedded Education and Prototyping.
Industrial Control and Automation
The ATMEGA324P-20MU fits industrial control panels because its 4.5 V to 5.5 V supply range delivers the noise immunity demanded in electrically harsh factory environments, where 3.3 V logic is more susceptible to coupled transients. Its two USARTs natively support RS-485 Modbus RTU slave communication, while three timers with PWM outputs drive heaters, valves or small motors directly. The 10-bit ADC digitizes analog sensor loops, and the watchdog timer provides autonomous fault recovery per IEC-style control practice. Mounted on a 7x7 mm VQFN with 32 GPIO lines, one MCU replaces glue logic, shift registers and a separate ADC, cutting BOM cost. In-circuit serial programming via the MPLAB SNAP allows firmware updates on installed equipment without desoldering.
推荐
Sensor Acquisition Nodes
For multi-channel sensor nodes, the ATMEGA324P-20MU combines a 10-bit ADC with the picoPower sleep architecture, letting battery-backed or line-powered nodes sample slowly varying signals at microamp average current. The 1 KB EEPROM stores calibration coefficients that survive power cycles, and 2 KB SRAM buffers sample blocks before transmission over either USART or the TWI (I2C) bus. Designers typically clock the part at reduced frequencies from the internal RC oscillator to cut active current roughly linearly with MHz, then wake via interrupt on the analog comparator or pin-change. The 44-pin VQFN exposes all 32 GPIOs, so digital sensor interfaces (one-wire, SPI) coexist with analog channels on a single footprint.
推荐
Motor Control and HVAC Systems
In HVAC controllers and light motor-control applications, the ATMEGA324P-20MU's three timers with compare modes generate complementary PWM drives for fans, dampers and compressor relays, while the 5 V logic directly interfaces opto-isolated gate drivers without level shifting. The 10-bit ADC reads thermistors and pressure sensors for closed-loop temperature control, and the byte-oriented TWI bus connects an external RTC for scheduling. Its -40C to +85C operating range covers rooftop and mechanical-room environments. Because two USARTs are available, one channel can service a building-management network while the other provides a service/diagnostic port. Flash read-while-write enables field firmware updates through a bootloader, an important maintenance feature for installed HVAC equipment.
推荐
Consumer Appliances
The ATMEGA324P-20MU is a proven choice for appliance user interfaces and main control boards: 32 GPIO lines drive seven-segment displays, keypads and relays directly at 5 V, eliminating level-translation circuitry required with 3.3 V MCUs. The internal oscillator removes the need for a crystal in timing-tolerant applications, and the programmable watchdog plus brown-out detection maintain safe behavior through mains dips. Its 32 KB Flash comfortably hosts touch-decoding, display-driving and communication stacks simultaneously. picoPower sleep modes meet standby-energy targets for appliances in idle state. The compact 7x7 mm VQFN with exposed pad solders reliably on standard reflow lines, and the same footprint supports the pin-compatible 324PA/324PB for cost or feature steering across product tiers.
推荐
Instrumentation and Test Equipment
Bench instruments, dongle testers and data loggers benefit from the ATMEGA324P-20MU's JTAG on-chip debugging and boundary-scan capability, which accelerate firmware development compared with debug-wire-only smaller AVRs. The dual USART architecture suits instruments that must simultaneously log data and expose a command console; 20 MHz execution at up to 1 MIPS/MHz handles menu systems and math on 10-bit ADC readings in real time. The 1 KB EEPROM retains calibration and unit serial numbers, and the read-while-write Flash allows logging into program-space-resident structures without stalling execution. Designers filter AVCC through an LC network to keep ADC noise below one LSB at 5 V reference, achieving approximately 4.9 mV resolution per code.
推荐
Embedded Education and Prototyping
The ATMEGA324P-20MU remains popular in university lab boards and professional prototyping because the 44-pin VQFN exposes four complete 8-bit ports (A through D), making every peripheral accessible on headers for oscilloscope-based teaching of timers, PWM, SPI and TWI. The AVR instruction set is well documented, toolchains such as avr-gcc and MPLAB X are free, and the MPLAB SNAP programmer costs a fraction of proprietary debug probes. In-system serial programming means students reflash boards without socketing. Because the footprint is shared with the ATMEGA644P and 164P, one lab PCB can host different memory variants, letting institutions scale exercise complexity without redesigning hardware - a cost and logistics advantage unique to this ATmega family.
推荐
推荐产品汇总
工程参考数据： ATMEGA324P-20MU ——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 | ATMEGA324P-20MQ | ATMEGA324PA-MU | ATMEGA324PB-MU | ATMEGA644P-20MU | ATMEGA164P-20MU |
|---|---|---|---|---|---|---|
| Package | 44-VQFN (7x7) | 44-VQFN (7x7) - same | 44-VQFN (7x7) - same | 44-VQFN (7x7) - same | 44-VQFN (7x7) - same | 44-VQFN (7x7) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 32 KB | 32 KB | 32 KB | 32 KB | 64 KB | 16 KB |
| SRAM | 2 KB | 2 KB | 2 KB | 4 KB | 4 KB | 1 KB |
| Max Clock Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| USART Count | 2 | 2 | 2 | 3 | 2 | 1 |
| Power Profile | picoPower standard | picoPower standard | picoPower, lower current (newer process) | picoPower, lower current | picoPower standard | picoPower standard |
关键差异点
- Dual USART in the mid-range ATmega tier （对比 ATMEGA164P-20MU)
- Lowest-cost entry into the 44-pin VQFN ATmega family （对比 ATMEGA644P-20MU)
- Lower power than the newer 324PB at identical pinout （对比 ATMEGA324PB-MU)
设计说明
Run the ATMEGA324P-20MU only within its 4.5 V to 5.5 V window for guaranteed 20 MHz operation; derating clock below that band is not supported on the non-V grade. Decouple VCC and AVCC each with 100 nF ceramics placed within 3 mm of the pins, and connect the exposed pad to a solid ground plane for both thermal and ground-integrity. Estimated: at 20 MHz and 5 V, active current is in the tens of mA range per AVR family behavior - verify exact ICC against the manufacturer datasheet tables for your supply budget.
The 44-VQFN (7x7) land pattern requires the center exposed pad soldered to ground for reliable operation - omitting the thermal via array is the most common reflow defect on this package. Use a 3x3 via grid under the pad with about 0.3 mm drills filled or tented. Route the JTAG/ISP header (reset plus two I/O pins per the MPLAB SNAP 8-pin SIL scheme) to a board edge connector so field firmware updates are possible without disassembly.
To preserve 10-bit ADC accuracy, filter AVCC through an LC network (for example 10 uH + 1 uF) separate from digital VCC and route analog traces away from USART/PWM switching lines. Use the internal bandgap or a precision external reference on AREF with a 100 nF bypass; never drive AREF while the internal reference is enabled, as this is a documented AVR failure mode. If the internal RC oscillator suffices, omit the crystal and free two I/O pins.
Migrating firmware to the pin-compatible ATMEGA324PB changes peripheral register maps (extra USART, different SPI naming), so binary hex files are NOT portable between 324P and 324PB despite identical footprints. Also note the ATMEGA324P-20AU is the TQFP package of the same die - it is not drop-in compatible with the MU VQFN footprint. Always confirm Brown-out Detection fuse settings when changing supply designs.
合规信息
Microchip current-production AVR parts are Pb-free/RoHS compliant (MU suffix denotes Pb-free VQFN per distributor listings); REACH and conflict-minerals status not stated in the provided data.