| PartNumber | ATMEGA645P-MU | ATMEGA645P-AU | ATMEGA645P-AUR |
| Description | 8-bit Microcontrollers - MCU AVR 64KB FLSH 2KB EE 4KB SRAM-16MHz, IND | 8-bit Microcontrollers - MCU AVR 64KB FLSH 2KB EE 4KB SRAM-16MHz, IND | Microcontrollers - MCU 8-bit Microcontrollers - MCU AVR 64KB FLSH 2KB EE 4KB SRAM-16MHz, IND |
| Manufacturer | Microchip | Microchip | Atmel |
| Product Category | 8-bit Microcontrollers - MCU | 8-bit Microcontrollers - MCU | Embedded - Microcontrollers |
| RoHS | Y | Y | - |
| Mounting Style | SMD/SMT | SMD/SMT | - |
| Package / Case | QFN-64 | TQFP-64 | - |
| Series | ATmega645P | ATmega645P | AVRR ATmega |
| Core | AVR | AVR | - |
| Data Bus Width | 8 bit | 8 bit | - |
| Maximum Clock Frequency | 16 MHz | 16 MHz | - |
| Program Memory Size | 64 kB | 64 kB | 64KB (32K x 16) |
| Data RAM Size | 4 kB | 4 kB | - |
| ADC Resolution | 10 bit | 10 bit | - |
| Number of I/Os | 54 I/O | 54 I/O | - |
| Operating Supply Voltage | 1.8 V to 5.5 V | 1.8 V to 5.5 V | - |
| Minimum Operating Temperature | - 40 C | - 40 C | - |
| Maximum Operating Temperature | + 85 C | + 85 C | - |
| Packaging | Tray | Tray | Digi-ReelR Alternate Packaging |
| Product | MCU | MCU | - |
| Program Memory Type | Flash | Flash | FLASH |
| Brand | Microchip Technology / Atmel | Microchip Technology / Atmel | - |
| Data RAM Type | SRAM | SRAM | - |
| Data ROM Size | 2 kB | 2 kB | - |
| Data ROM Type | EEPROM | EEPROM | - |
| Interface Type | SPI, USART | SPI, USART | - |
| Moisture Sensitive | Yes | Yes | - |
| Number of ADC Channels | 8 Channel | 8 | - |
| Number of Timers/Counters | 2 x 8 bit, 1 x 16 bit | 3 Timer | - |
| Processor Series | megaAVR | megaAVR | - |
| Product Type | 8-bit Microcontrollers - MCU | 8-bit Microcontrollers - MCU | - |
| Factory Pack Quantity | 260 | 90 | - |
| Subcategory | Microcontrollers - MCU | Microcontrollers - MCU | - |
| Supply Voltage Max | 5.5 V | 5.5 V | - |
| Supply Voltage Min | 1.8 V | 1.8 V | - |
| Tradename | AVR | AVR | - |
| Watchdog Timers | Watchdog Timer | - | - |
| Unit Weight | - | 0.012720 oz | - |
| Package Case | - | - | 64-TQFP |
| Operating Temperature | - | - | -40°C ~ 85°C (TA) |
| Supplier Device Package | - | - | 64-TQFP (14x14) |
| Number of I O | - | - | 54 |
| Speed | - | - | 16MHz |
| EEPROM Size | - | - | 2K x 8 |
| Core Processor | - | - | AVR |
| RAM Size | - | - | 4K x 8 |
| Peripherals | - | - | Brown-out Detect/Reset, POR, PWM, WDT |
| Connectivity | - | - | SPI, UART/USART, USI |
| Voltage Supply Vcc Vdd | - | - | 1.8 V ~ 5.5 V |
| Core Size | - | - | 8-Bit |
| Data Converters | - | - | A/D 8x10b |
| Oscillator Type | - | - | Internal |