ATMEGA128A-AUR - 8-Bit AVR MCU 128KB Flash 16MHz TQFP-64 | Microchip
料号： ATMEGA128A-AUR ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $5.2 | $5.20 |
| 10 | $4.68 | $46.80 |
| 100 | $4.16 | $416.00 |
| 500 | $3.64 | $1,820.00 |
| 1,000 | $3.12 | $3,120.00 |
ATMEGA128A-AUR 概述
An 8-bit microcontroller (MCU) is a self-contained computing device that integrates a processor core, memory, and programmable peripherals on a single silicon die. The ATmega128A belongs to the AVR family of microcontrollers, positioned within the broader hierarchy of embedded processors under the power-management and control-system category. AVR MCUs execute powerful instructions in a single clock cycle, achieving throughputs approaching 1 MIPS per MHz, allowing system designers to optimize power consumption versus processing speed.
Key features include an advanced RISC architecture with 133 powerful instructions, most of which execute in a single clock cycle; 32 general-purpose working registers; four flexible timer/counters with compare modes and PWM channels; two USARTs for serial communication; and a byte-oriented two-wire serial interface (TWI/I2C) plus SPI. The 16MHz maximum clock frequency delivers approximately 16 MIPS of throughput at 5V operation.
The device operates from a single supply of 2.7V to 5.5V, supporting both 3.3V and 5V system designs. Flash memory supports in-system programming (ISP) through the SPI port, enabling firmware updates after board assembly without removing the device. Read-while-write flash capability allows firmware execution during EEPROM or flash programming operations.
Typical applications include industrial control and factory automation, sensor and data-acquisition systems, motor and power-control nodes, building automation, and legacy embedded designs where a mature, well-documented AVR platform with ample flash is required. The 53 I/O lines and external memory interface make it well suited to designs driving keypads, displays, and multiple serial links simultaneously.
For design, note that flash programming voltage and bootloader considerations affect layout: reserve access to the SPI pins (PB0-PB3) for ISP programming headers. Decouple VCC pins with 100nF ceramics placed close to each supply pin.
This page synthesizes distributor pricing, drop-in alternatives, pinout data, and practical design notes not found in the manufacturer datasheet, providing a single reference for sourcing and design decisions.
直接替换替代料： ATMEGA128A-AUR ——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： ATMEGA128A-AUR （相同外形与封装尺寸） ——差异在于 Package, Flash Memory, SRAM, Supply Voltage Range, ADC.
快速对比工具——选择替代料号进行并排对比：
ATMEGA128-16AU
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$14.3 / 个
查看数据手册 →ATMEGA128A-AU
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$4.3 / 个
查看数据手册 →ATMEGA128-16MUR
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$8.4 / 个
查看数据手册 →ATMEGA1284-AUR
✅ 直接替换✓ 有现货
$4.61 / 个
查看数据手册 →ATMEGA1284P-MUR
✅ 直接替换✓ 有现货
联系询价
查看数据手册 →ATMEGA1281V-8AUR
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$4.4 / 个
查看数据手册 →ATMEGA128A-AUR 最大额定值与电气特性
| Core Architecture | AVR 8-bit RISC |
| Flash Memory | 128KB (64K x 16) In-System Programmable |
| EEPROM | 4KB |
| SRAM | 4KB |
| 最大时钟频率 | 16 MHz |
| Supply Voltage Range | 2.7 V to 5.5 V |
| I/O Lines | 53 |
| Working Registers | 32 general purpose |
| Instruction Set | 133 powerful instructions, most single-cycle |
| Timers/Counters | 4 flexible timer/counters with compare modes and PWM |
| USARTs | 2 |
| Serial Interfaces | TWI (I2C), SPI, 2x USART |
| 封装 | 64-TQFP (14x14 mm) |
| 安装类型 | Surface Mount |
| Real-Time Counter | Yes |
ATMEGA128A-AUR 引脚配置
| 引脚 1 | PE0 — Port E bit 0 / RXD0 (USART0 receive) |
| 引脚 2 | PE1 — Port E bit 1 / TXD0 (USART0 transmit) |
| 引脚 3 | PE2 — Port E bit 2 / XCK0 / AIN0 |
| 引脚 4 | PE3 — Port E bit 3 / OC3A / AIN1 |
| 引脚 5 | PE4 — Port E bit 4 / OC3B / INT4 |
| 引脚 6 | PE5 — Port E bit 5 / OC3C / INT5 |
| 引脚 7 | PE6 — Port E bit 6 / T3 / INT6 |
| 引脚 8 | PE7 — Port E bit 7 / ICP3 / INT7 |
| 引脚 9 | GND — Ground |
| 引脚 10 | VCC — Digital supply voltage |
| 引脚 11 | PB0 — Port B bit 0 / SS (SPI slave select) |
| 引脚 12 | PB1 — Port B bit 1 / SCK (SPI clock) |
| 引脚 13 | PB2 — Port B bit 2 / MOSI |
| 引脚 14 | PB3 — Port B bit 3 / MISO |
| 引脚 15 | PB4 — Port B bit 4 / OC0 / OC2 (PWM) |
| 引脚 16 | PB5 — Port B bit 5 / OC1A (PWM) |
| 引脚 17 | PB6 — Port B bit 6 / OC1B (PWM) |
| 引脚 18 | PB7 — Port B bit 7 / OC2 / OC1C (PWM) |
| 引脚 19 | PF0 — Port F bit 0 / ADC0 |
| 引脚 20 | RESET — Reset input (active low) |
| 引脚 21 | PF1 — Port F bit 1 / ADC1 |
| 引脚 22 | PF2 — Port F bit 2 / ADC2 |
| 引脚 23 | PF3 — Port F bit 3 / ADC3 |
| 引脚 24 | PF4 — Port F bit 4 / ADC4 / TCK (JTAG) |
| 引脚 25 | PF5 — Port F bit 5 / ADC5 / TMS (JTAG) |
| 引脚 26 | PF6 — Port F bit 6 / ADC6 / TDO (JTAG) |
| 引脚 27 | PF7 — Port F bit 7 / ADC7 / TDI (JTAG) |
| 引脚 28 | AREF — Analog reference voltage for ADC |
| 引脚 29 | GND — Ground |
| 引脚 30 | AVCC — Analog supply voltage for ADC |
| 引脚 31 | PA0 — Port A bit 0 / ADC0 / external memory address/data line A0/D0 |
| 引脚 32 | PA1 — Port A bit 1 / ADC1 / external memory A1/D1 |
| 引脚 33 | PA2 — Port A bit 2 / ADC2 / external memory A2/D2 |
| 引脚 34 | PA3 — Port A bit 3 / ADC3 / external memory A3/D3 |
| 引脚 35 | PA4 — Port A bit 4 / ADC4 / external memory A4/D4 |
| 引脚 36 | PA5 — Port A bit 5 / ADC5 / external memory A5/D5 |
| 引脚 37 | PA6 — Port A bit 6 / ADC6 / external memory A6/D6 |
| 引脚 38 | PA7 — Port A bit 7 / ADC7 / external memory A7/D7 |
| 引脚 39 | PC0 — Port C bit 0 / external memory address line A8 |
| 引脚 40 | PC1 — Port C bit 1 / external memory address line A9 |
| 引脚 41 | PC2 — Port C bit 2 / external memory address line A10 |
| 引脚 42 | PC3 — Port C bit 3 / external memory address line A11 |
| 引脚 43 | PC4 — Port C bit 4 / external memory address line A12 |
| 引脚 44 | PC5 — Port C bit 5 / external memory address line A13 |
| 引脚 45 | PC6 — Port C bit 6 / external memory address line A14 |
| 引脚 46 | PC7 — Port C bit 7 / external memory address line A15 |
| 引脚 47 | GND — Ground |
| 引脚 48 | VCC — Digital supply voltage |
| 引脚 49 | PD0 — Port D bit 0 / SCL (TWI) / INT0 |
| 引脚 50 | PD1 — Port D bit 1 / SDA (TWI) / INT1 |
| 引脚 51 | PD2 — Port D bit 2 / RXD1 (USART1) / INT2 |
| 引脚 52 | PD3 — Port D bit 3 / TXD1 (USART1) / INT3 |
| 引脚 53 | PD4 — Port D bit 4 / ICP1 (input capture) |
| 引脚 54 | PD5 — Port D bit 5 / XCK1 |
| 引脚 55 | PD6 — Port D bit 6 / T1 (timer 1 external clock) |
| 引脚 56 | PD7 — Port D bit 7 / T2 (timer 2 external clock) |
| 引脚 57 | PG0 — Port G bit 0 / WR (external memory write strobe) |
| 引脚 58 | PG1 — Port G bit 1 / RD (external memory read strobe) |
| 引脚 59 | PG2 — Port G bit 2 / ALE (external memory address latch enable) |
| 引脚 60 | XTAL1 — Crystal/oscillator input |
| 引脚 61 | XTAL2 — Crystal/oscillator output |
| 引脚 62 | PG3 — Port G bit 3 / TOSC2 (RTC crystal output) |
| 引脚 63 | PG4 — Port G bit 4 / TOSC1 (RTC crystal input) |
| 引脚 64 | VCC — Digital supply voltage |
典型应用
ATMEGA128A-AUR 适用于 6 应用s: Industrial Control and Factory Automation, Building Automation and HVAC Controllers, Data Acquisition and Sensor Systems, Legacy Design Continuation and Board Spins, Motor Control and Power Electronics Supervision, Embedded Communication and Gateway Nodes.
Industrial Control and Factory Automation
The ATMEGA128A-AUR suits industrial control nodes because its 53 general-purpose I/O lines, four timer/counters with PWM, and two USARTs can simultaneously drive relays, read limit switches, and communicate with SCADA gateways over RS-485 (via USART). Operating from 2.7V to 5.5V with industrial temperature rating, it tolerates noisy factory power rails. Its 128KB flash with bootloader section supports field firmware updates on deployed machinery without removing the device from the PCB. In a typical PLC expansion module, the 16MHz core executes control loops approaching 16 MIPS, sufficient for sequential control and monitoring tasks, while the external memory interface allows expansion when logging requires more RAM than the internal 4KB SRAM provides.
推荐
Building Automation and HVAC Controllers
Building automation panels need many I/O, multiple serial buses, and low unit cost - the ATMEGA128A-AUR delivers all three. Its byte-oriented TWI (I2C) interface connects environmental sensors (temperature, humidity, CO2), while the two USARTs handle BACnet/Modbus front ends and an RS-485 trunk. The 4KB EEPROM retains setpoints and schedules through power outages, and the real-time counter supports time-of-day scheduling with a 32.768kHz watch crystal on the TOSC pins. The 2.7-5.5V supply range allows a single 5V rail derived from mains power. The 128KB flash comfortably hosts protocol stacks plus a bootloader for remote firmware updates over the building network.
推荐
Data Acquisition and Sensor Systems
For multi-channel data acquisition, the ATMEGA128A-AUR's port PA doubles as the ADC input multiplex while port PC serves the external memory bus, letting one chip manage eight analog channels and parallel ADCs or external SRAM simultaneously. The four timer/counters generate precise sampling clocks and PWM excitation signals for sensor bridges. With throughput near 1 MIPS per MHz at 16MHz, DSP-light tasks such as filtering and scaling complete in real time. The industrial temperature range suits unconditioned field enclosures, and the two USARTs stream results to a host or radio module. The 2.7V floor supports 3.3V-only designs where the ADC reference and sensor front ends run at lower rails.
推荐
Legacy Design Continuation and Board Spins
Many PCBs designed around the ATmega103 or original ATmega128 remain in production, and the ATMEGA128A-AUR is the sanctioned continuation path: Microchip documents that the ATmega128A is 100% pin compatible with the ATmega103 and directly replaces it on current printed circuit boards, and it shares the ATmega128's 64-TQFP footprint and peripheral map. Engineers refreshing EOL assemblies can drop in the ATmega128A-AUR without layout changes, revalidating only firmware errata items. Keeping the SPI ISP header on these boards preserves in-field reprogramming, and the active lifecycle status ensures long-term supply compared with sourcing older, allocation-prone dies.
推荐
Motor Control and Power Electronics Supervision
The ATMEGA128A-AUR supervises small motor drives and power stages using its four timer/counters: two 8-bit and 16-bit timers provide complementary PWM channels with compare modes for DC motor speed control and servo positioning. The external interrupt pins (INT0-INT7 across ports D and E) capture quadrature encoder or zero-cross signals, while USART connectivity reports status to a higher-level controller. The 5V-tolerant industrial part drives MOSFET gate-driver ICs directly through its PWM outputs with appropriate buffering. Its deterministic single-cycle RISC execution keeps current-loop timing jitter low, and the 4KB EEPROM stores calibration constants such as offset, gain, and thermal limits across power cycles.
推荐
Embedded Communication and Gateway Nodes
With two independent USARTs plus SPI plus TWI, the ATMEGA128A-AUR bridges dissimilar buses in compact gateway nodes - for example, translating Modbus RTU on RS-485 to a proprietary SPI radio link, or buffering sensor data from a TWI sensor cluster to a cellular modem. The 128KB flash hosts protocol stacks, buffers, and a boot loader for remote updates delivered over either UART. At 16MHz the core sustains sustained serial throughput at 115200 baud on both UARTs with headroom for framing and CRC computation. The 53 I/O lines handle DIP-switch address selection, status LEDs, and flow-control handshakes, consolidating gateway logic into a single low-cost MCU.
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推荐产品汇总
工程参考数据： ATMEGA128A-AUR ——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 | ATMEGA128-16AU | ATMEGA128A-AU | ATMEGA1284-AUR | ATMEGA1281V-8AUR |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 64-TQFP (14x14 mm) | 64-TQFP - same | 64-TQFP - same | 64-TQFP - same | 64-TQFP - same |
| Flash Memory | 128KB | 128KB | 128KB | 128KB | 128KB |
| SRAM | 4KB | 4KB | 4KB | 16KB | 8KB |
| Max Clock Frequency | 16 MHz | 16 MHz | 16 MHz | 20 MHz | 8 MHz |
| Supply Voltage | 2.7 V to 5.5 V | 4.5 V to 5.5 V (16MHz grade) | 2.7 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| Lifecycle Status | Active | Not recommended for new designs (superseded) | Active | Active | Active |
关键差异点
- Active lifecycle continuation of the ATmega128 legacy core （对比 ATMEGA128-16AU)
- 100% pin compatibility with ATmega103 for board revivals （对比 ATMEGA1284-AUR)
- 53 I/O lines with external memory interface （对比 ATMEGA1281V-8AUR)
设计说明
The ATMEGA128A-AUR requires supply decoupling on every VCC pin (10, 48, 64) - fit a 100nF ceramic within 5mm of each pin, plus one bulk 10uF per board. At 5V and 16MHz, active-mode current is in the tens of milliamp range (exact figure: consult the Microchip datasheet current-consumption tables). When running below 4.5V, derate the maximum clock frequency per the AVR frequency-versus-voltage curve to avoid illegal timing; a 3.3V design should target 8MHz crystals unless the datasheet curve confirms a higher safe speed.
Reserve the SPI pins (PB0-PB3, pins 11-14) for an in-circuit ISP programming header - a 6-pin or 10-pin AVR ISP layout. Ensure series resistors isolate the ISP header from peripheral loads on SCK/MOSI/MISO so programming is not disturbed during operation. Keep the XTAL1/XTAL2 crystal (pins 60-61) traces short and guard them with ground pour; the ATmega128A also supports the TOSC 32.768kHz crystal on PG3/PG4 (pins 62-63) for the real-time counter - route it away from the main crystal to prevent coupling.
Migrating from ATmega103 or original ATmega128: the ATmega128A is pin-compatible, but fuse defaults, JTAG enable state (JTAG shares PF4-PF7, pins 24-27), and certain peripheral errata differ. If PF4-PF7 are needed as ADC inputs, disable JTAG via fuse in software sequence or at programming time. Also note RESET (pin 20) must not be pulled above VCC; a 10k pull-up plus optional reset supervisor improves noise immunity in industrial environments. Verify bootloader fuse (BOOTRST) settings before field deployment.
When the external memory interface is used, ports PA (pins 31-38) and PC (pins 39-46) switch the heaviest loads; keep these bus traces under 100mm and add 22-33 ohm series resistors on ALE (PG2, pin 59), WR (PG0, pin 57), and RD (PG1, pin 58) to control ringing. Ground return paths for the bus should reference pin 47 GND, which sits directly adjacent to port PC on this pinout, minimizing loop area for address/data switching noise.
合规信息
Distributor listings (DigiKey/Mouser) present the ATMEGA128A-AUR as a current RoHS-compliant, lead-free industrial MCU. REACH and halogen-free status require confirmation from Microchip's material declaration documents.