ATMEGA128A-AU - 8-bit AVR MCU 128KB Flash 16MHz TQFP-64 | Microchip
N.º de pieza: ATMEGA128A-AU ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $7.2 | $7,20 |
| 10 | $6.48 | $64,80 |
| 100 | $5.55 | $555,00 |
| 500 | $4.9 | $2.450,00 |
| 1.000 | $4.3 | $4.300,00 |
ATMEGA128A-AU Descripción general
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a processor core, program memory, data memory and peripherals such as timers, serial interfaces and ADCs. Within the power-management and embedded-system hierarchy, the ATmega MCU family sits in the general-purpose embedded controller class, executing powerful instructions in a single clock cycle to deliver throughputs close to 1 MIPS per MHz.
Key differentiating features include the AVR enhanced RISC architecture with 133 instructions (most single-cycle) and 32 general-purpose working registers, read-while-write Flash for self-programming, a real-time counter (RTC), four flexible timer/counters with compare modes and PWM, two USARTs, a byte-oriented Two-Wire serial interface (TWI/I2C), an SPI serial port, and an 8-channel 10-bit ADC with optional differential inputs. JTAG boundary-scan and on-chip debug simplify production testing.
The core operates from 2.7 V to 5.5 V. The AVR Harvard architecture achieves deterministic single-cycle execution, and the ATmega128A is fabricated on an improved process relative to the original ATmega128, giving significantly lower power consumption. Power-saving idle, ADC noise reduction and power-down modes suit battery-operated designs.
Typical applications include legacy industrial control upgrades, building automation and HVAC controllers, instrumentation and data loggers, and hobby/education boards where a pin-compatible replacement for the classic ATmega128 or ATmega103 is required without PCB redesign.
Design consideration: maximum clock frequency is supply-voltage dependent - verify the 16 MHz rating is used only at the upper supply range, and decouple AVCC/AREF carefully for ADC accuracy.
This page synthesizes distributor pricing tiers, verified drop-in alternatives, and practical design notes not found in the manufacturer datasheet summary.
Alternativas directas para ATMEGA128A-AU — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con ATMEGA128A-AU (mismo factor de forma y huella) — difiere en RoHS Status, Flash Memory, Operating Temperature, Package, Supply Voltage Range.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
ATMEGA128-16MUR
✅ Sustitución directa✓ En stock
$8.4 / unidad
Ver hoja de datos →ATMEGA128-16AN
✅ Sustitución directa✓ En stock
$7.44 / unidad
Ver hoja de datos →ATMEGA128L-8AU
✅ Sustitución directa ⚠️ Especificaciones sin verificar✓ En stock
$23.49 / unidad
Ver hoja de datos →ATMEGA128L-8AI
✅ Sustitución directa ⚠️ Especificaciones sin verificar✓ En stock
$6.6 / unidad
Ver hoja de datos →ATMEGA103-8AI
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
ATMEGA128A-AU Valores máximos y características eléctricas
| Core Processor | AVR |
| Core Size | 8-Bit |
| Architecture | Enhanced RISC, 133 instructions |
| Max Clock Frequency | 16 MHz |
| Flash Memory | 128 KB (64K x 16), In-System Programmable, read-while-write |
| EEPROM | 4 KB |
| SRAM | 4 KB |
| Supply Voltage Range | 2.7 V to 5.5 V |
| General Purpose I/O | 53 lines |
| Working Registers | 32 general purpose |
| Timers/Counters | 4 flexible timer/counters with compare modes and PWM |
| Communication Interfaces | 2x USART, TWI (I2C), SPI |
| ADC | 8-channel, 10-bit |
| Real-Time Counter | Yes (RTC) |
| Debug / Boundary Scan | JTAG (IEEE 1149.1) |
| Encapsulado | 64-TQFP (14x14 mm) |
| Tipo de montaje | Surface Mount |
| Projected End of Life | 2048-10-03 (per distributor lifecycle data) |
Guía de configuración de pines de ATMEGA128A-AU 64-tqfp (14x14 mm)
Configuración de pines para ATMEGA128A-AU (encapsulado 64-tqfp (14x14 mm)). Este CI digital incluye GPIO, interfaces de comunicación (UART, SPI, I2C) y pines de alimentación. Consulte la hoja de datos del fabricante para conocer las funciones alternativas de los pines y las opciones de configuración. Esencial para el diseño de sistemas embebidos y el diseño de PCB.
No hay datos detallados de patillaje disponibles para ATMEGA128A-AU.
Consulte la hoja de datos para ver la configuración completa de patillas.
Aplicaciones típicas
ATMEGA128A-AU es adecuado para 6 aplicacións: Legacy Industrial Control Upgrades, Building Automation and HVAC Controllers, Instrumentation and Data Loggers, Communication Gateways and Protocol Converters, Motor Control and Power Electronics Panels, Education, Prototyping and Maker Boards.
Legacy Industrial Control Upgrades
The ATMEGA128A-AU fits legacy industrial control upgrades because it is 100% pin-compatible with the ATmega128 and ATmega103 in the same 64-TQFP (14x14 mm) footprint, allowing existing PCBs to be re-populated without layout changes. Its 128 KB Flash, 4 KB EEPROM and 4 KB SRAM match the original memory map, while the improved process lowers operating current relative to the classic ATmega128. Two USARTs handle Modbus RTU and fieldbus links, and the external-memory interface (ALE, WR, RD on port G with 16-bit address ports) supports legacy SRAM or memory-mapped I/O expansion. Distributor lifecycle data projects end-of-life at 2048-10-03, giving service organizations a long procurement horizon for board-level repairs.
Recomendado
Building Automation and HVAC Controllers
In building automation and HVAC controllers, the ATMEGA128A-AU combines the 8-channel 10-bit ADC needed for temperature, humidity and pressure sensor acquisition with TWI (I2C) for digital sensors and two USARTs for RS-485/RS-232 networking. The 53 GPIO lines drive relays, dampers and displays, while four timer/counters with PWM outputs control fans and valve actuators directly. The real-time counter with a separate 32 kHz oscillator maintains time-of-day scheduling even in power-down mode, and read-while-write Flash allows parameter logging in the 4 KB EEPROM without halting program execution. Operation from 2.7 V to 5.5 V simplifies powering from 24 V industrial rails via a linear or switching regulator.
Recomendado
Instrumentation and Data Loggers
For instrumentation and data-logging products, the ATMEGA128A-AU offers a deterministic 1 MIPS-per-MHz AVR core, making timestamped sampling loops predictable. The 8-channel 10-bit ADC with differential inputs and internal reference handles multi-sensor front ends, while 128 KB Flash accommodates large lookup tables, calibration curves and even field-updatable firmware via the read-while-write self-programming feature. The 4 KB EEPROM retains configuration across power cycles, and JTAG boundary-scan (IEEE 1149.1) supports production test on automated fixtures. Power-saving idle, ADC noise reduction and power-down modes extend battery life in portable loggers, with the RTC keeping timestamps alive at microamp-level sleep currents.
Recomendado
Communication Gateways and Protocol Converters
The dual USARTs of the ATMEGA128A-AU make it a natural fit for serial protocol converters, translating between RS-232, RS-485 and TTL links at up to 16 MHz clock rates. The byte-oriented TWI (I2C) and SPI interfaces allow bridging to EEPROMs, RTCs, displays and sensor hubs, while 4 KB SRAM buffers frames for store-and-forward conversion. Hardware compare-match timers generate precise baud-rate clocks, and the 32 general-purpose registers keep interrupt service routines fast for deterministic latency. Because the device is a drop-in for the widely deployed ATmega128, thousands of proven gateway firmware bases can be re-used directly on the improved A-version silicon with lower power draw.
Recomendado
Motor Control and Power Electronics Panels
Panel-level motor starters and lighting controllers benefit from the four timer/counters with compare modes and PWM outputs of the ATMEGA128A-AU, which generate gate or drive signals for DC motors, blowers and LED drivers. The 10-bit ADC samples current shunts and potentiometers, and input-capture pins measure tachometer periods for closed-loop speed regulation. The 5.5 V supply ceiling matches directly-driven optocoupler and gate-driver front ends, and JTAG enables in-system debugging of safety interlock logic. Designers should pair the MCU with dedicated gate drivers and protection devices, since the GPIO lines supply only logic-level drive current.
Recomendado
Education, Prototyping and Maker Boards
The ATMEGA128A-AU remains a staple of embedded-systems education and maker prototyping because the AVR architecture is well documented, the toolchain (AVR-GCC, avrdude, JTAG ICE) is mature and free, and the 64-pin TQFP exposes 53 GPIO plus all major peripherals for breadboard-adapted carrier boards. Students learn real register-level programming with 133 single-cycle instructions and 32 working registers, while the In-System Programmable Flash supports bootloader-based development without external programmers. Because the part is pin-compatible with the ATmega128, university lab boards and open-source hardware designs designed a decade ago continue to accept the A-version directly, protecting long-lived teaching infrastructure investments.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para ATMEGA128A-AU — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | ATMEGA128-16MUR | ATMEGA128-16AN | ATMEGA128L-8AU | ATMEGA128L-8AI | ATMEGA103-8AI |
|---|---|---|---|---|---|---|
| Package | 64-TQFP (14x14 mm) | 64-TQFP - same | 64-TQFP - same | 64-TQFP - same | 64-TQFP - same | 64-TQFP - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Atmel (Microchip Technology) |
| Flash Memory | 128 KB | 128 KB | 128 KB | 128 KB | 128 KB | 128 KB |
| Max Clock Frequency | 16 MHz | 16 MHz | 16 MHz | 8 MHz | 8 MHz | 8 MHz |
| Supply Voltage | 2.7 V to 5.5 V | 4.5 V to 5.5 V (16 MHz grade) | 4.5 V to 5.5 V (16 MHz grade) | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 4.0 V to 5.5 V |
| SRAM / EEPROM | 4 KB / 4 KB | 4 KB / 4 KB | 4 KB / 4 KB | 4 KB / 4 KB | 4 KB / 4 KB | 4 KB / 4 KB |
| Power Consumption | Lower (improved A-version process) | Higher (original process) | Higher (original process) | Low-voltage family, lower clock current | Low-voltage family, lower clock current | Higher (legacy process) |
| Pin Compatibility | Baseline (ATmega128/ATmega103 footprint) | 100% pin-to-pin | 100% pin-to-pin | 100% pin-to-pin | 100% pin-to-pin | 100% pin compatible per datasheet |
Diferenciadores clave
- Process-improved lower power consumption (frente a ATMEGA128-16MUR)
- Full 16 MHz speed grade (frente a ATMEGA128L-8AU)
- Active lifecycle with long supply horizon (frente a ATMEGA103-8AI)
- Trade-off: fewer I/O than newer megaAVR (frente a ATMEGA1284P-MU)
Notas de diseño
The ATMEGA128A-AU is rated to 16 MHz only within the appropriate supply-voltage window; the L-variants are limited to 8 MHz at lower voltages. Derate the maximum clock against VCC using the speed-grade curve in the full ATmega128A datasheet before fixing your crystal. Supply AVCC separately through an LC filter (ferrite bead plus 100 nF) even if tied to VCC at the regulator, because ADC accuracy depends on a quiet AVCC. Estimated: at 5 V and 16 MHz, active current is in the tens of milliamps class per the family datasheet - size the 3.3 V/5 V regulator accordingly.
Place 100 nF ceramic decoupling capacitors at each VCC/GND pair (pins 10/11, 41/42, 52/53) as close to the TQFP leads as possible, plus one bulk 10 uF per rail. Keep the XTAL1/XTAL2 crystal traces short and guarded by ground, and route the JTAG (TCK/TMS/TDO/TDI on PF4-PF7) header away from the analog front end. Preserve test points on RESET (pin 51), PEN (pin 1) and both USARTs so production programming and field diagnostics remain possible on dense legacy-replacement boards.
Migrating from ATmega103: although pin compatibility is 100%, register addresses, fuse bytes and some peripheral behaviors differ - follow the Microchip application note 'Replacing ATmega103 by ATmega128A' and expect firmware changes for fuse configuration and extended I/O mapping. Do not assume the original ATmega128 current-consumption figures: the A-version is lower-power, so sleep-current-based battery calculations should be re-validated. Finally, erase cycles on the 4 KB EEPROM are limited - wear-level parameter writes rather than logging to EEPROM at high frequency.
Información de cumplimiento
RoHS compliance and lead-free construction indicated by distributor comparison data (Xecor). REACH, halogen-free and conflict-minerals status not stated in the provided data - request official Microchip environmental certificates for the specific date code.