ATMEGA645P-AU - 8-bit AVR MCU 64KB Flash 16MHz TQFP-64 | Microchip
N.º da peça: ATMEGA645P-AU ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $6.38 | $6,38 |
| 10 | $5.86 | $58,60 |
| 100 | $5.36 | $536,00 |
| 500 | $4.92 | $2.460,00 |
| 1.000 | $4.6 | $4.600,00 |
ATMEGA645P-AU Visão geral
An 8-bit AVR microcontroller is a Harvard-architecture processor that executes most instructions in a single clock cycle. Within the power-management hierarchy, it combines a CPU core, program memory, data memory, and peripheral controllers (timers, UART, SPI, TWI/I2C, ADC) on a single semiconductor die, replacing multi-chip board-level solutions and reducing BOM cost and board area.
Key differentiating features include the picoPower technology platform for low active and sleep-mode consumption, read-while-write Flash for self-programming and bootloader applications, 32 general-purpose working registers directly connected to the ALU, an on-chip 10-bit ADC, and In-Circuit Serial Programming ICSP via just two I/O pins plus reset, supported by tools such as the MPLAB SNAP debugger.
Architecturally, the AVR RISC core achieves roughly 1 MIPS per MHz, so at the maximum 16 MHz clock the ATmega645P delivers close to 16 MIPS throughput. The picoPower process family (the P-suffix generation) supersedes the non-P ATmega645 with lower power figures while remaining a documented drop-in replacement under Microchip application note AVR534.
Typical applications include industrial control panels, HVAC and building automation, battery-powered instrumentation, consumer appliances, and embedded human-machine interfaces where a 5V-tolerant, flash-based 8-bit MCU with rich I/O count is preferred.
Design consideration: choose the clock source and bod (brown-out detector) settings carefully at 5V versus 3.3V operation, since the guaranteed 16 MHz maximum frequency applies to the 4.5V to 5.5V range; at 2.7V to 5.5V the safe maximum is lower per the datasheet frequency-versus-voltage curve.
This page synthesizes distributor pricing, verified drop-in alternatives, application guidance, and comparison tables not found in the manufacturer datasheet, with pricing as of 2026-09-18.
Alternativas drop-in para ATMEGA645P-AU — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Variantes desta série
Modelos da mesma série compatíveis como drop-in com ATMEGA645P-AU (mesmo formato e footprint) — diferindo em Package, Flash Memory, RoHS Status, Operating Temperature, SRAM.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
ATMEGA645A-AU
✅ Drop-In✓ Em estoque
$3.95 / unidade
Ver ficha técnica →ATMEGA6450P-AU
✅ Drop-In✓ Em estoque
$5.9 / unidade
Ver ficha técnica →ATMEGA649P-AU
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
ATMEGA645-16AI
✅ Drop-In ⚠️ Especificações não verificadas✓ Em estoque
$6.45 / unidade
Ver ficha técnica →ATMEGA64-16AU
✅ Drop-In ⚠️ Especificações não verificadas✓ Em estoque
$7.23 / unidade
Ver ficha técnica →ATMEGA644P-20PQ
✅ Drop-In ⚠️ Especificações não verificadas✓ Em estoque
$7.4 / unidade
Ver ficha técnica →ATMEGA645P-AU Classificações máximas e características elétricas
| Core Architecture | 8-bit AVR RISC |
| Flash Memory | 64 KB (32K x 16) ISP |
| EEPROM | 2 KB |
| SRAM | 4 KB |
| Frequência máxima de clock | 16 MHz |
| Supply Voltage Range | 2.5 V to 5.5 V |
| General Purpose I/O | 54 lines |
| Working Registers | 32 x 8-bit general purpose |
| Encapsulamento | 64-TQFP (14 x 14 mm) |
| Tipo de montagem | Surface Mount |
| Temperatura de operação | -40C to +85C (Industrial) |
| Programming Interface | ICSP (In-Circuit Serial Programming) |
| Debug Support | debugWIRE via MPLAB SNAP |
| Low Power Technology | picoPower |
| Approximate Throughput | up to 16 MIPS at 16 MHz (1 MIPS/MHz) |
| Status RoHS | Compliant (Green package per Microchip listings) |
Guia de Configuração de Pinos do ATMEGA645P-AU 64-tqfp (14 x 14 mm)
Configuração de pinos para ATMEGA645P-AU (pacote 64-tqfp (14 x 14 mm)). Este CI digital inclui GPIO, interfaces de comunicação (UART, SPI, I2C) e pinos de alimentação. Consulte o datasheet do fabricante para funções alternativas dos pinos e opções de configuração. Essencial para projeto de sistemas embarcados e layout de PCB.
Nenhum dado detalhado de pinagem disponível para ATMEGA645P-AU.
Consulte a ficha técnica para a configuração completa dos pinos.
Aplicações típicas
ATMEGA645P-AU é adequado para 6 aplicaçãos: Industrial Control Panels, Battery-Powered Instrumentation, HVAC and Building Automation, Consumer Appliances, Embedded Human-Machine Interfaces, Hobby, Education, and Legacy Maintenance.
Industrial Control Panels
The ATMEGA645P-AU fits industrial control panels because its 54 GPIO lines drive buttons, relays, indicator LEDs, and limit-switch inputs directly without port expanders, while the 5.5V-tolerant AVR I/O structure suits legacy 5V industrial signal levels. The 64KB ISP Flash with read-while-write supports field-updatable firmware via bootloader, and the industrial -40C to +85C temperature rating matches cabinet-mounted electronics. The AVR core executes most instructions in one cycle, giving roughly 16 MIPS at 16 MHz for deterministic scanning of I/O loops and Modbus-style polling over the on-chip UART or TWI. Using ICSP via MPLAB SNAP keeps in-field programming to a two-wire-plus-reset header, and picoPower sleep modes cut idle consumption in always-on installations.
Recomendado
Battery-Powered Instrumentation
For portable meters, dataloggers, and handheld instruments, the ATMEGA645P-AU's picoPower technology delivers very low sleep-mode current, extending battery life in duty-cycled designs that wake on timer or external interrupt. The 4KB SRAM buffers logging sessions locally while 2KB EEPROM stores calibration constants through power cycles, and the on-chip 10-bit ADC samples sensor channels without an external converter. Operating down to 2.5V lets a single lithium cell pair through an LDO run the full 64KB Flash program. Because the AVR executes one instruction per clock, engineers meet measurement deadlines at low clock rates, further trimming current; the TQFP-64's many I/O also accommodate keypad, LCD, and USB-bridge interfaces in one MCU.
Recomendado
HVAC and Building Automation
In thermostats, zone controllers, and rooftop-unit boards, the ATMEGA645P-AU integrates the on-chip TWI (I2C-compatible) and SPI peripherals to manage temperature sensors, EEPROM configuration memory, and display drivers over two-wire buses, while its 54 GPIO drive dampers, triac zones, and fan controls. The industrial temperature rating survives mechanical rooms and rooftop enclosures, and the 64KB Flash holds protocol stacks plus schedules. picoPower sleep modes matter in battery-backed thermostats where the controller must retain state through outages; wake-on-interrupt from the real-time timer restores operation quickly. Flash self-programming with read-while-write enables OTA-style updates during maintenance windows without replacing hardware, protecting long-lived building installations.
Recomendado
Consumer Appliances
White goods, small kitchen appliances, and power tools benefit from the ATMEGA645P-AU's combination of robust 5V-tolerant I/O, on-chip ADC for NTC temperature and motor-current sensing, and 16 MHz performance for user-interface responsiveness. The 64KB Flash accommodates multi-language UI code, safety routines, and wear-leveling for EEPROM settings storage. AVR's single-cycle execution supports precise motor-control timing loops and encoder decoding in firmware without external logic. The TQFP-64 package reflows on standard lead-free assembly lines and provides enough I/O for touch keys, seven-segment displays, and relay banks on a single controller, cutting BOM cost versus multi-chip solutions while the green RoHS-compliant package meets global appliance regulations.
Recomendado
Embedded Human-Machine Interfaces
The ATMEGA645P-AU suits HMI panels and operator terminals: its GPIO count handles a keypad matrix plus segment or small graphic display buses simultaneously, while 4KB SRAM holds framebuffer segments and menu state. The single-cycle AVR core drives display refresh and touch-scan timers deterministically, and the UART links the panel to a main controller or PC. 64KB Flash stores fonts, bitmaps, and multilingual string tables, and read-while-write self-programming allows logging of operator events into Flash without halting the UI. Because the same 64-TQFP footprint is shared with ATMEGA6450P and ATMEGA649P variants, one PCB can be populated with the LCD-controller-equipped 649P when a segment LCD is added, giving a scalable HMI platform.
Recomendado
Hobby, Education, and Legacy Maintenance
Universities, makerspaces, and service organizations continue to standardize on 8-bit AVR TQFP-64 parts because ICSP programming needs only two I/O pins plus reset, working with inexpensive MPLAB SNAP programmers and open-source toolchains. The ATMEGA645P-AU's 64KB Flash gives students room for complex projects - USB bridges, retro-computer cores, and instrument firmware - while the datasheet's complete register-level documentation teaches real embedded fundamentals. For legacy equipment maintenance, the family's long availability and the documented AVR534 migration path from ATmega645/645P keep replacement boards manufacturable; the drop-in compatibility across the 645, 645A, and 645P generations lets repair shops substitute whichever variant is in stock without PCB changes.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para ATMEGA645P-AU — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | ATMEGA645A-AU | ATMEGA6450P-AU | ATMEGA649P-AU | ATMEGA64-16AU | ATMEGA644P-20PQ |
|---|---|---|---|---|---|---|
| Package | 64-TQFP (14x14 mm) | 64-TQFP (14x14 mm) - same | 64-TQFP (14x14 mm) - same | 64-TQFP (14x14 mm) - same | 64-TQFP (14x14 mm) - same | 64-TQFP - same footprint class, verify pinout |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 64 KB | 64 KB | 64 KB | 64 KB | 64 KB | 64 KB |
| SRAM | 4 KB | 4 KB | 4 KB | 4 KB | 4 KB | 4 KB |
| EEPROM | 2 KB | 2 KB | 2 KB | 2 KB | 2 KB | 2 KB |
| Max Clock Frequency | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 20 MHz |
| GPIO Count | 54 | 54 | 54+ (extended mapping) | 54+ (some I/O shared with LCD) | 53 | 32 |
| Low Power Generation | picoPower (P generation) | Non-picoPower (A generation) | picoPower | picoPower | Non-picoPower | picoPower |
| Pin-to-Pin Compatibility | Reference | Full (AVR534 documented) | Same family footprint, minor mapping review | Same footprint, LCD-shared pins differ | All but a few pins (AVR500) | Not guaranteed - verify pinout |
Principais diferenciais
- picoPower low-power generation (vs ATMEGA645A-AU)
- Clean general-purpose I/O allocation (vs ATMEGA649P-AU)
- Documented drop-in migration path (vs ATMEGA64-16AU)
- Trade-off: lower max frequency than 644P (vs ATMEGA644P-20PQ)
Notas de projeto
Match clock speed to supply voltage: the 16 MHz maximum for ATMEGA645P-AU is guaranteed at the top of the 2.5V-5.5V range (4.5V-5.5V); at 3.3V operation, derate the maximum frequency per the datasheet frequency-vs-voltage curve to avoid marginal timing. Enable brown-out detection (BOD) scaled to the operating rail so Flash writes corrupt nothing during brownouts, and place 100 nF ceramic decoupling capacitors at each VCC/GND pair plus a 10 uF bulk capacitor near the TQFP-64 supply entry.
Reserve the ICSP header (MOSI, MISO, SCK, RESET, VCC, GND) on every production PCB even when pre-programmed parts are used, since the MPLAB SNAP connects through an 8-pin SIL connector using two I/O pins plus reset for both programming and debugWIRE debugging. Keep crystal traces to XTAL1/XTAL2 short with guard ground, and route the RESET trace away from switching noise; RESET doubles as the debugWIRE pin so a 10 kOhm pull-up is the standard value.
Do not assume cross-family pin compatibility: Microchip AVR500 explicitly states ATmega64 and ATmega645 are 'not designed to be a replacement device for each other' and differ on a few pins, and ATMEGA644P shares only the package class. When substituting ATMEGA645A-AU for this part (or vice versa), review the AVR534 electrical-characteristics delta table - power figures differ between picoPower and non-picoPower generations even though the footprint is identical.
Estimated: with 54 GPIO at up to 20 mA absolute-maximum per pin, keep total simultaneous sink/source current within the datasheet per-port and total-package limits (typically 100 mA/class per port and 200 mA total - verify exact values in the current datasheet revision) and use adequate ground return vias under the TQFP-64 thermal center to keep ground bounce low when driving many outputs simultaneously.
Informações de conformidade
RoHS compliance and lead-free finish per Microchip green package listings for the ATmega645P family -AU package. Obtain formal REACH, halogen-free, and conflict-minerals declarations from Microchip's product compliance portal; not independently verified here.
