ATMEGA8A-AU - AVR 8-bit MCU 16MHz 8KB Flash TQFP-32 | Microchip
N.º de pieza: ATMEGA8A-AU ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $2.45 | $2,45 |
| 10 | $2.15 | $21,50 |
| 100 | $1.78 | $178,00 |
| 500 | $1.52 | $760,00 |
| 1.000 | $1.31 | $1.310,00 |
ATMEGA8A-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, UART, SPI, I2C and ADC on one silicon die. Within the power management and embedded-systems hierarchy, the MCU sits at the top of the control chain, reading sensors and driving actuators; the ATmega8A belongs to the AVR family from Microchip Technology (formerly Atmel), one of the most widely deployed 8-bit MCU architectures in education and industry.
Key features include the advanced AVR RISC architecture with 130 powerful instructions, most executing in a single clock cycle; a 2-cycle on-chip hardware multiplier; 10-bit ADC with up to 8 single-ended channels; and high-endurance non-volatile memory segments rated for 10,000 Flash and 100,000 EEPROM write cycles. The device runs from 4.5 V to 5.5 V at full 16 MHz speed, per the datasheet supply range for the -16 speed grade.
Architecturally, the AVR core uses 32 x 8 general-purpose working registers directly connected to the ALU, achieving fully static operation and eliminating the accumulator bottleneck of classic 8051-style designs. Harvard memory architecture separates program and data buses for parallel instruction fetch.
Typical applications include industrial control panels, consumer appliance interfaces, motor control, sensor nodes, and legacy Arduino-compatible boards using the MiniCore hardware package.
Design consideration: at 16 MHz choose the 4.5-5.5 V supply window; for 3.3 V battery systems use the ATmega8L (8 MHz max) speed-grade variant instead.
This page synthesizes distributor pricing, drop-in alternatives such as the ATmega88A family, and practical design notes not found in the manufacturer datasheet.
Alternativas directas para ATMEGA8A-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 ATMEGA8A-AU (mismo factor de forma y huella) — difiere en Package, ADC, Operating Temperature, Maximum Clock Frequency, Timers.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
ATMEGA8A-AN
✅ Sustitución directa✓ En stock
$1.58 / unidad
Ver hoja de datos →ATMEGA88A-AU
✅ Sustitución directa✓ En stock
$1.52 / unidad
Ver hoja de datos →ATMEGA88PA-AUR
✅ Sustitución directa✓ En stock
$0.82 / unidad
Ver hoja de datos →ATMEGA88V-10AU
✅ Sustitución directa✓ En stock
$1.58 / unidad
Ver hoja de datos →ATMEGA88PB-ANR
✅ Sustitución directa✓ En stock
$1.38 / unidad
Ver hoja de datos →ATMEGA8-16AI
✅ Sustitución directa✓ En stock
$2.46 / unidad
Ver hoja de datos →ATMEGA8A-AU Valores máximos y características eléctricas
| Core Architecture | 8-bit AVR RISC |
| Frecuencia de reloj máxima | 16 MHz |
| Flash Program Memory | 8 KB (4K x 16) |
| EEPROM | 512 B |
| SRAM | 1 KB |
| I/O Pins | 23 |
| Supply Voltage Range | 4.5 V to 5.5 V (at 16 MHz) |
| Throughput | Up to 16 MIPS at 16 MHz |
| Instructions | 130 instructions, most single-cycle |
| Hardware Multiplier | On-chip 2-cycle multiplier |
| ADC | 10-bit, 6 multiplexed channels (8 on TQFP/QFN incl. ADC6/ADC7) |
| Communication Interfaces | 1x USART, SPI, TWI (I2C) |
| Timers | 2x 8-bit, 1x 16-bit timer/counter |
| Analog Comparator | Yes, on-chip |
| Flash Endurance | 10,000 write cycles |
| EEPROM Endurance | 100,000 write cycles |
| Encapsulado | 32-TQFP (7x7 mm, 0.8 mm pitch) |
| Tipo de montaje | Surface Mount |
| Programming / Debug | In-Circuit Serial Programming (ICSP) via SPI, MPLAB SNAP supported |
| Estado del ciclo de vida | Active |
Configuración de pines de ATMEGA8A-AU
| Pin 1 | PD3 (INT1) — Port D bit 3 / External Interrupt 1 |
| Pin 2 | PD4 (XCK/T0) — Port D bit 4 / USART External Clock / Timer0 external clock |
| Pin 3 | GND — Ground |
| Pin 4 | VCC — Digital supply voltage |
| Pin 5 | GND — Ground |
| Pin 6 | VCC — Digital supply voltage |
| Pin 7 | PB6 (XTAL1/TOSC1) — Port B bit 6 / Crystal oscillator input / Timer oscillator input |
| Pin 8 | PB7 (XTAL2/TOSC2) — Port B bit 7 / Crystal oscillator output / Timer oscillator output |
| Pin 9 | PD5 (T1) — Port D bit 5 / Timer1 external counter input |
| Pin 10 | PD6 (AIN0) — Port D bit 6 / Analog comparator positive input |
| Pin 11 | PD7 (AIN1) — Port D bit 7 / Analog comparator negative input |
| Pin 12 | PB0 (ICP1) — Port B bit 0 / Timer1 input capture |
| Pin 13 | PB1 (OC1A) — Port B bit 1 / Timer1 PWM output A |
| Pin 14 | PB2 (SS/OC1B) — Port B bit 2 / SPI slave select / Timer1 PWM output B |
| Pin 15 | PB3 (MOSI/OC2) — Port B bit 3 / SPI master output / Timer2 PWM output |
| Pin 16 | PB4 (MISO) — Port B bit 4 / SPI master input |
| Pin 17 | PB5 (SCK) — Port B bit 5 / SPI serial clock |
| Pin 18 | AVCC — ADC supply voltage |
| Pin 19 | ADC6 — ADC input channel 6 (TQFP/QFN packages only) |
| Pin 20 | AREF — ADC analog reference voltage |
| Pin 21 | GND — Ground |
| Pin 22 | ADC7 — ADC input channel 7 (TQFP/QFN packages only) |
| Pin 23 | PC0 (ADC8) — Port C bit 0 / ADC channel 8 |
| Pin 24 | PC1 (ADC9) — Port C bit 1 / ADC channel 9 |
| Pin 25 | PC2 (ADC10) — Port C bit 2 / ADC channel 10 |
| Pin 26 | PC3 (ADC11) — Port C bit 3 / ADC channel 11 |
| Pin 27 | PC4 (SDA/ADC12) — Port C bit 4 / TWI data line / ADC channel 12 |
| Pin 28 | PC5 (SCL/ADC13) — Port C bit 5 / TWI clock line / ADC channel 13 |
| Pin 29 | PC6 (RESET) — Reset input (active low) / Port C bit 6 |
| Pin 30 | PD0 (RXD) — Port D bit 0 / USART receive |
| Pin 31 | PD1 (TXD) — Port D bit 1 / USART transmit |
| Pin 32 | PD2 (INT0) — Port D bit 2 / External Interrupt 0 |
Aplicaciones típicas
ATMEGA8A-AU es adecuado para 6 aplicacións: Industrial Control and Automation, Consumer Appliance Control, Sensor Nodes and Data Acquisition, Hobby and Arduino-Compatible Education, Motor Control and Power Electronics, Communication Interfaces and Legacy Retrofit.
Industrial Control and Automation
The ATMEGA8A-AU fits industrial control panels because its 4.5-5.5 V supply matches standard 5 V logic rails, its 23 I/O lines drive relays and optocouplers directly, and its 10-bit ADC reads 0-5 V transducer signals without external conversion. The three timers generate PWM for actuator control, while SPI and TWI link HMI displays and EEPROM storage. Fully static operation across 0-16 MHz allows undervolting the clock to reduce emissions in noisy factory environments. With 10,000-cycle Flash endurance supporting field firmware updates and a 16 MIPS core handling scan loops in the microsecond range, it covers PLC auxiliary logic, motor start sequencers, and sensor hubs at a fraction of the cost of 32-bit MCUs.
Recomendado
Consumer Appliance Control
White goods, small kitchen appliances, and HVAC controllers benefit from the ATMEGA8A-AU's cost structure and robustness. The 8 KB Flash holds complete appliance state machines including button debouncing, buzzer melodies, and display multiplexing for 7-segment LED panels driven through the 23 I/O pins. The on-chip analog comparator provides zero-cross detection for triac-based heater and motor phase control without an external comparator IC. At 16 MHz the 2-cycle hardware multiplier accelerates PID temperature-control loops. Its active lifecycle status and multi-source distributor availability (Octopart lists 10 distributors) reduce end-of-life risk for products with 5-10 year service commitments, and the 5 V operation tolerates noisy appliance power environments well.
Recomendado
Sensor Nodes and Data Acquisition
The ATMEGA8A-AU integrates a 10-bit successive-approximation ADC with 6 multiplexed channels (8 including the dedicated ADC6/ADC7 pins on the TQFP-32), plus AVCC and AREF pins that enable clean analog reference design - well suited to multi-channel sensor acquisition. TWI (I2C) and SPI interfaces connect digital sensors such as temperature, pressure, and accelerometers, while the USART streams readings at up to 1 Mbps to a gateway. The 512 B EEPROM stores calibration constants that survive power loss, eliminating external NV memory. Because the ADC noise depends heavily on AVCC filtering, adding an RC filter on AVCC yields effective resolution near 10 bits in quiet designs, adequate for environmental monitoring, metering front-ends, and hobby instrumentation.
Recomendado
Hobby and Arduino-Compatible Education
The ATmega8A is a staple of electronics education and maker projects: the MCUdude MiniCore Arduino hardware package on GitHub provides first-class Arduino IDE support for ATmega8, ATmega48/88/168/328 devices. The ATMEGA8A-AU in TQFP-32 suits compact custom boards, while its DIP sibling ATmega8-16PU fits breadboards. With 16 MIPS at 16 MHz, it comfortably runs Arduino core functions, servo libraries, and NeoPixel drivers. Its low unit cost (around $2.45 as of 2026-09-19) makes classroom and club purchasing practical, and the enormous AVR documentation base, community tutorials, and ISP programmer compatibility (USBasp, MPLAB SNAP) shorten the learning curve for students transitioning from graphical to C/C++ embedded programming.
Recomendado
Motor Control and Power Electronics
The ATMEGA8A-AU generates up to three PWM channels from its two 8-bit timers and one 16-bit timer, supporting DC motor speed control, fan drivers, and basic BLDC trapezoidal commutation with Hall inputs on the interrupt-capable pins. The analog comparator with selectable reference handles overcurrent trip detection with microsecond-class response, and the 16-bit timer captures input pulses for tachometer feedback. Because the 5 V I/O drives standard MOSFET gate-driver inputs directly, the typical design pairs the MCU with an H-bridge driver IC. Firmware tables stored in Flash implement commutation lookup and ramp profiles, and the 8 KB code space is sufficient for complete closed-loop speed controllers in fans, pumps, and power tools.
Recomendado
Communication Interfaces and Legacy Retrofit
The ATMEGA8A-AU's full-duplex USART, hardware SPI, and TWI (I2C) make it an effective protocol bridge and legacy-system retrofit controller: converting RS-232 equipment to USB-adjacent TTL links, adding modem handling to aging machinery, or acting as an I2C-to-SPI translator between mismatched subsystems. The USART supports framing-error and parity detection for robust field communication, and the AVR's deterministic single-cycle core lets interrupt-driven UART servicing run alongside timing-critical tasks. In retrofit scenarios, its 5 V I/O tolerance connects directly to legacy TTL logic levels without level shifters. The 10,000-cycle Flash endurance supports on-site firmware re-flashing during equipment service cycles, which is valuable for long-lifetime industrial communication nodes.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para ATMEGA8A-AU — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | ATMEGA8A-AN | ATMEGA88A-AU | ATMEGA88PA-AUR | ATMEGA88V-10AU | ATMEGA88PB-ANR | ATMEGA8-16AI |
|---|---|---|---|---|---|---|---|
| Package | TQFP-32 (7x7 mm) | TQFP-32 (7x7 mm) - same | TQFP-32 (7x7 mm) - same | TQFP-32 (7x7 mm) - same | TQFP-32 (7x7 mm) - same | TQFP-32 (7x7 mm) - same | TQFP-32 (7x7 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock / Throughput | 16 MHz / 16 MIPS | 16 MHz / 16 MIPS | 20 MHz / 20 MIPS | 20 MHz / 20 MIPS | 10 MHz / 10 MIPS | 20 MHz / 20 MIPS | 16 MHz / 16 MIPS |
| Flash Memory | 8 KB | 8 KB | 8 KB | 8 KB | 8 KB | 8 KB | 8 KB |
| SRAM | 1 KB | 1 KB | 1 KB | 1 KB | 1 KB | 1 KB | 1 KB |
| Firmware Compatibility | Baseline (ATmega8 register map) | Identical - same die | Migration required (AVR094) | Migration required (AVR094) | Migration required (AVR094) | Migration required | Identical register map |
| Lifecycle Status | Active | Active | Active | Active | Active | Active | Original die - availability declining |
Diferenciadores clave
- Zero-migration ATmega8 firmware compatibility (frente a ATMEGA88A-AU)
- Lowest effective cost for legacy maintainers (frente a ATMEGA88PB-ANR)
- 8 ADC channels on TQFP package (frente a ATMEGA8-16PI (DIP-28))
Notas de diseño
Decouple both VCC pins (4 and 6) and AVCC (pin 18) individually with 100 nF ceramic capacitors placed within 5 mm of each pin, plus one bulk 10 uF per board section. AVCC must be connected to VCC even if the ADC is unused, per the Microchip datasheet - if ADC is used, filter AVCC through an LC network (10 uH + 100 nF) to reduce supply-coupled ADC noise. GND pins 3, 5 and 21 should connect to a solid ground plane to minimize ground bounce across the 23 switching I/O lines.
The TQFP-32 has a 0.8 mm pitch; specify a solder mask-defined pad of about 0.55 mm with 0.35 mm trace widths for reliable reflow. Keep the crystal (pins 7/8) within 10 mm of the package with 22 pF load capacitors matched to the crystal spec, and guard the XTAL traces with ground. Route the RESET line (pin 29) away from PWM outputs; a 10 kOhm pull-up on RESET is mandatory for stable ICSP programming and noise immunity during power ramp.
The most frequent ATmega8A design errors: (1) leaving PC6/RESET floating causes sporadic resets - always add the pull-up; (2) exceeding the 4.5-5.5 V speed window - running this -16 grade below 4.5 V at 16 MHz violates the guaranteed operating envelope, use the L or 88V grades for low voltage; (3) migrating firmware to pin-compatible ATmega88 without reviewing the different interrupt vector table and register names described in Microchip application note AVR094; (4) forgetting that ADC6/ADC7 exist only on TQFP/QFN packages - DIP designs have 6 ADC channels instead of 8.
Información de cumplimiento
Compliance status not stated in the provided web data; verify on the official Microchip ATmega8A product page compliance documentation.
