ATMEGA644P-15AT - 8-bit AVR MCU 64KB Flash 16MHz TQFP-44 | Microchip
N.º de pieza: ATMEGA644P-15AT ✗ Fin de vida| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $6.42 | $6,42 |
| 10 | $5.78 | $57,80 |
| 100 | $5.15 | $515,00 |
| 500 | $4.61 | $2.305,00 |
| 1.000 | $4.12 | $4.120,00 |
ATMEGA644P-15AT Descripción general
A microcontroller (MCU) is a single-chip computer that integrates a processor core, program memory (Flash), data memory (SRAM), non-volatile storage (EEPROM), and peripherals such as timers, serial interfaces, and analog-to-digital converters. Within the AVR ATmega hierarchy, the ATmega644P sits in the mid-to-high range: ATmega48 < ATmega88 < ATmega164P < ATmega324P < ATmega644P < ATmega1284, all built on the AVR 8-bit RISC core with Atmel picoPower technology for reduced active and sleep-mode current.
Key differentiating features include 32 general-purpose I/O lines, two USARTs (the 'P' suffix denotes the dual-USART enhancement over the original ATmega644), an 8-channel 10-bit ADC with optional differential mode and programmable gain, a byte-oriented 2-wire serial interface (TWI/I2C), SPI, three flexible Timer/Counters with PWM, a Real-Time Counter, and a programmable Watchdog Timer. In-system programmable Flash with Read-While-Write capability allows firmware updates without chip removal.
Typical applications include industrial automation nodes, embedded sensor data acquisition with the 10-bit ADC, RS-232/RS-485 communication gateways using dual USARTs, hobbyist/Arduino-compatible designs (supported by the MightyCore hardware package), and AEC-Q100 grade 1 qualified automotive-adjacent systems where -40C to +85C operation is required.
When designing, observe the 10x10 mm TQFP land pattern, decouple VCC and AVCC, and verify external crystal drive levels. The two-cycle load/store architecture and Harvard memory layout are transparent to C code but influence interrupt latency. Be aware that ATMEGA644P-15AT is mature and not recommended for new designs - the ATmega644PA successor is preferred.
This page synthesizes verified distributor listings, AEC-Q100 qualification references, drop-in family alternatives (including the ATmega644PA successor), and practical design notes not consolidated in the manufacturer datasheet.
Alternativas directas para ATMEGA644P-15AT — 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 ATMEGA644P-15AT (mismo factor de forma y huella) — difiere en Package, ADC, Core Architecture, EEPROM, RoHS Status.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
ATMEGA644PA-AU
✅ Sustitución directa✓ En stock
$4.61 / unidad
Ver hoja de datos →ATMEGA644PA-MU
✅ Sustitución directa✓ En stock
$3.78 / unidad
Ver hoja de datos →ATMEGA644P-20AU
✅ Sustitución directa✓ En stock
$3.95 / unidad
Ver hoja de datos →ATMEGA644PA-AUR
✅ Sustitución directa ⚠️ Especificaciones sin verificar✓ En stock
$1.78 / unidad
Ver hoja de datos →ATMEGA1284P-AU
✅ Sustitución directa✓ En stock
$4.65 / unidad
Ver hoja de datos →ATMEGA324PV-10AU
✅ Sustitución directa✓ En stock
$4.3 / unidad
Ver hoja de datos →ATMEGA164A-AU
✅ Sustitución directa✓ En stock
$2.65 / unidad
Ver hoja de datos →ATMEGA644P-15AT Valores máximos y características eléctricas
| Core Architecture | AVR 8-bit enhanced RISC |
| Program Memory (Flash) | 64 KB (32K x 16) |
| SRAM | 4 KB |
| EEPROM | 2 KB |
| Frecuencia de reloj máxima | 16 MHz (at 5V) |
| Throughput | Up to 1 MIPS per MHz (16 MIPS peak) |
| Operating Voltage (VCC) | 2.7 V to 5.5 V |
| General-Purpose I/O Lines | 32 |
| ADC | 8-channel, 10-bit, with differential mode |
| USART | 2 (dual USART, 'P' variant) |
| SPI | 1 master/slave |
| TWI (I2C) | 1 byte-oriented |
| Timer/Counters | 3 with PWM and compare modes |
| Watchdog Timer | Yes, programmable |
| Encapsulado | 44-pin TQFP (10x10 mm) |
| Tipo de montaje | Surface Mount |
| Temperatura de funcionamiento | -40C to +85C (industrial) |
| AEC-Q100 Qualification | Grade 1 |
| Estado RoHS | Compliant |
| In-System Programmable | Yes (Flash, Read-While-Write) |
| picoPower Technology | Yes |
Configuración de pines de ATMEGA644P-15AT
| Pin 1 | VCC — Digital supply voltage (5V nominal) |
| Pin 2 | GND — Digital ground |
| Pin 3 | AVCC — Analog supply voltage |
| Pin 4 | AGND — Analog ground |
| Pin 5 | AREF — ADC reference voltage |
| Pin 6 | ADC0 — Analog input channel 0 |
| Pin 7 | ADC1 — Analog input channel 1 |
| Pin 8 | ADC2 — Analog input channel 2 |
| Pin 9 | ADC3 — Analog input channel 3 |
| Pin 10 | ADC4 — Analog input channel 4 |
| Pin 11 | ADC5 — Analog input channel 5 |
| Pin 12 | ADC6 — Analog input channel 6 |
| Pin 13 | ADC7 — Analog input channel 7 |
| Pin 14 | PC0 — Port C bit 0 (GPIO) |
| Pin 15 | PC1 — Port C bit 1 (GPIO) |
| Pin 16 | PC2 — Port C bit 2 (GPIO) |
| Pin 17 | PC3 — Port C bit 3 (GPIO) |
| Pin 18 | PC4 — Port C bit 4 (GPIO) |
| Pin 19 | PC5 — Port C bit 5 (GPIO) |
| Pin 20 | PC6 — Port C bit 6 (GPIO) |
| Pin 21 | PC7 — Port C bit 7 (GPIO) |
| Pin 22 | PA0 — Port A bit 0 (GPIO) |
| Pin 23 | PA1 — Port A bit 1 (GPIO) |
| Pin 24 | PA2 — Port A bit 2 (GPIO) |
| Pin 25 | PA3 — Port A bit 3 (GPIO) |
| Pin 26 | PA4 — Port A bit 4 (GPIO) |
| Pin 27 | PA5 — Port A bit 5 (GPIO) |
| Pin 28 | PA6 — Port A bit 6 (GPIO) |
| Pin 29 | PA7 — Port A bit 7 (GPIO) |
| Pin 30 | VCC — Digital supply voltage (second pad) |
| Pin 31 | GND — Digital ground (second pad) |
| Pin 32 | XTAL2 — Crystal oscillator output |
| Pin 33 | XTAL1 — Crystal oscillator input |
| Pin 34 | PD0 — Port D bit 0 (RXD0 / GPIO) |
| Pin 35 | PD1 — Port D bit 1 (TXD0 / GPIO) |
| Pin 36 | PD2 — Port D bit 2 (RXD1 / GPIO) |
| Pin 37 | PD3 — Port D bit 3 (TXD1 / GPIO) |
| Pin 38 | PD4 — Port D bit 4 (GPIO) |
| Pin 39 | PD5 — Port D bit 5 (GPIO) |
| Pin 40 | PD6 — Port D bit 6 (GPIO) |
| Pin 41 | PD7 — Port D bit 7 (GPIO) |
| Pin 42 | RESET — Reset input (active low) |
| Pin 43 | PB0 — Port B bit 0 (GPIO) |
| Pin 44 | PB1 — Port B bit 1 (GPIO) |
Aplicaciones típicas
ATMEGA644P-15AT es adecuado para 6 aplicacións: Industrial Sensor Data Acquisition, RS-232 / RS-485 Communication Gateway, Hobbyist / Arduino-Compatible Custom Boards, Automotive-Adjacent Control Nodes, Embedded Control with TWI / SPI Peripherals, PWM and Timer-Control Applications.
Industrial Sensor Data Acquisition
The ATMEGA644P-15AT is well suited for industrial sensor data acquisition nodes. Its 8-channel, 10-bit ADC with optional differential inputs and programmable gain handles bridge-style sensors (load cells, strain gauges) and 4-20 mA loops with external conditioning. The 16 MHz core delivers 16 MIPS, fast enough to oversample the ADC and apply digital filtering in firmware. The 4 KB data SRAM buffers multi-channel scans before serial upload, while 64 KB Flash stores calibration coefficients in the EEPROM (2 KB). Dual USARTs support simultaneous RS-485 sensor bus and debug console. Operating temperature -40C to +85C covers most industrial cabinets. AEC-Q100 Grade 1 qualification supports automotive-adjacent sites. Compact 10x10 mm TQFP-44 footprint fits dense PLC modules.
Recomendado
RS-232 / RS-485 Communication Gateway
Dual USARTs make the ATMEGA644P-15AT a natural choice for protocol-conversion gateways. One port can interface to RS-232 (e.g. legacy instruments, GPS modules) while the other drives an RS-485 bus (Modbus RTU, DMX512, proprietary industrial protocols). The 16 MHz throughput easily handles 115200 baud with DMA-style polling plus protocol parsing. 4 KB SRAM buffers incoming Modbus frames before forwarding, and 64 KB Flash stores protocol stacks and configuration. Hardware CRC and the USART error-detection flags reduce software overhead. TQFP-44 fits standard gateway enclosures, and 5V tolerance simplifies interface to industrial transceivers like MAX485 or MAX3232. Consider ATmega644PA-AU for lower quiescent current in battery-backed installations.
Recomendado
Hobbyist / Arduino-Compatible Custom Boards
The ATMEGA644P-15AT is widely supported by the MightyCore Arduino hardware package, which adds ATmega644/P/PA board variants to the Arduino IDE. Its 64 KB Flash hosts full sketches with bootloader, the 4 KB SRAM is generous for Arduino-style String operations, and 32 digital pins (plus analog) suit many hobby projects. The dual USARTs allow simultaneous USB-serial programming and GPS or Bluetooth modules. The 16 MHz @ 5V core matches the Arduino Uno timing, easing code porting. TQFP-44 fits hand-solderable breakout boards; users wanting QFN prefer the -MU. For new designs the ATmega644PA-AU is recommended, but existing P-based projects continue to work. The 10-bit ADC is adequate for hobby analog sensors (light, temperature, potentiometers).
Recomendado
Automotive-Adjacent Control Nodes
AEC-Q100 Grade 1 qualification allows the ATMEGA644P-15AT to serve in automotive-adjacent control nodes such as body controllers, HVAC sub-modules, sensor clusters, and aftermarket accessories. The 64 KB Flash stores application code plus CAN-style protocol tables; the 2 KB EEPROM records calibration and fault logs that survive key-off cycles. The 8-channel 10-bit ADC reads thermistors, potentiometers, and battery-voltage dividers. Dual USARTs can drive a LIN bus via external transceiver plus a debug port. The -40C to +85C operating range covers cabin and underhood-near-side locations. picoPower modes lower quiescent draw during key-off. For new automotive designs Microchip recommends the ATmega644PA family with equivalent or better automotive qualification and improved sleep currents.
Recomendado
Embedded Control with TWI / SPI Peripherals
The ATMEGA644P-15AT combines a hardware TWI (I2C) interface and an SPI master/slave port, supporting simultaneous displays, sensors, and external memory. Typical setups use TWI for an I2C OLED or character LCD plus an RTC chip (e.g. DS3231), and SPI for an SD-card logger or high-speed ADC. The 16 MIPS throughput handles 8 MHz SPI transfers to SD cards with FAT filesystem overhead. The 32 GPIO lines can bit-bang additional peripherals when hardware ports are busy, useful for WS2812 LED chains or custom LCD interfaces. 4 KB SRAM holds the FAT directory cache and a small framebuffer. The 10x10 mm TQFP-44 layout fits handheld datalogger enclosures.
Recomendado
PWM and Timer-Control Applications
Three flexible 16-bit Timer/Counters with PWM and compare modes make the ATMEGA644P-15AT effective for motor-drive, lighting, and power-conversion control. Phase-correct PWM at 16 MHz / 256 resolution yields ~62 kHz carrier with 8-bit duty control, or 122 Hz at 16-bit resolution. Three timers drive multi-phase BLDC commutation, three independent LED channels, or a synchronous buck converter's switch / synchronous rectifier pair. The Programmable Watchdog Timer prevents firmware lockup in unattended installations, and the Real-Time Counter with separate oscillator handles timekeeping in sleep modes. The 32 GPIO lines dedicate the rest of the part to feedback signals (encoder, current sense, fault). Robust 5V I/O tolerates industrial transients.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para ATMEGA644P-15AT — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | ATMEGA644PA-AU | ATMEGA644PA-MU | ATMEGA644P-20AU | ATMEGA1284P-AU | ATMEGA324PV-10AU |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-pin TQFP (10x10 mm) | 44-pin TQFP (10x10 mm) - same | 44-pin TQFP (10x10 mm) - same | 44-pin TQFP (10x10 mm) - same | 44-pin TQFP (10x10 mm) - same | 44-pin TQFP (10x10 mm) - same |
| Flash | 64 KB | 64 KB | 64 KB | 64 KB | 128 KB | 32 KB |
| SRAM | 4 KB | 4 KB | 4 KB | 4 KB | 16 KB | 2 KB |
| EEPROM | 2 KB | 2 KB | 2 KB | 2 KB | 4 KB | 1 KB |
| Max Clock | 16 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 10 MHz (low-voltage) |
| Operating Voltage | 2.7 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 2.7 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| Dual USART | Yes | Yes | Yes | Yes | Yes | Yes |
| picoPower | Yes | Yes | Yes | Yes | Yes | Yes |
| Lifecycle | Mature (not for new designs) | Active | Active | Mature | Active | Active |
Diferenciadores clave
- Officially designated as the mature successor's predecessor (frente a ATMEGA644PA-AU)
- 20 MHz vs 16 MHz speed grade (frente a ATMEGA644P-20AU)
- Larger memory option in same TQFP-44 footprint (frente a ATMEGA1284P-AU)
Notas de diseño
The ATMEGA644P-15AT operates from 2.7 V to 5.5 V; AVCC must track VCC within +/- 0.3 V to keep the ADC reference valid. Place a 100 nF decoupling capacitor close to each VCC/AVCC pin, plus a bulk 10 uF tantalum or ceramic near the package. The MCU supports several sleep modes (Idle, ADC Noise Reduction, Power-save, Power-down, Standby, Extended Standby) drawing as little as sub-1 uA in Power-down; wake on Watchdog or external interrupt. The picoPower features on the PA successor lower active current by 25-50% versus the P die. For battery-powered designs, switch the PA family; for line-powered designs the P is fine.
The 44-pin TQFP package has 0.8 mm pitch - manageable for hand-soldering but requires a precise reflow profile for production. Use a 4-layer PCB with a continuous ground plane beneath the part; route ADC traces away from digital switching lines and keep the AVCC trace short and wide. The exposed pad (if present on the QFN variant) must be soldered to the ground plane for thermal dissipation. Crystal traces should be short and symmetric, with the load capacitors placed close to XTAL1/XTAL2. Place the ISP 6-pin header near the MCU to avoid long programming-cable traces that pick up noise.
Common pitfalls with the ATMEGA644P-15AT: (1) forget that the part needs a reset decoupling capacitor on pin 42 (typically 10 kohm pull-up + 100 nF to ground for an RC delay); (2) ignore the fuse settings - the default clock source is the internal 8 MHz RC oscillator, not an external crystal; configure the appropriate low-power crystal fuse bits before relying on accurate timing; (3) leave Brown-Out Detector disabled - enable BOD for robust industrial behavior; (4) use the wrong ISP signature - the ATmega644P and ATmega644A signatures differ, ensure your IDE/compiler is pointed at the correct device; (5) confuse the ATmega644 (single USART) with the ATmega644P (dual USART) - verify the part marking; (6) place too much code in the bootloader section and overflow into application Flash; (7) the 2 KB EEPROM supports 100k write cycles - design firmware to write sparingly and use wear-leveling for parameters that change often.
Información de cumplimiento
AEC-Q100 Grade 1 qualified per Microchip qualification documentation. RoHS and REACH compliant per DigiKey and Mouser listings. Halogen-free per Atmel/Microchip product environmental compliance documentation.