| PartNumber | AT89LP51ED2-20AAU | AT89LP51ED2-20JU | AT89LP51ED2-20AU |
| Description | 8-bit Microcontrollers - MCU 64KB 20MHz 2.4V-5.5V | 8-bit Microcontrollers - MCU 64KB 20MHz 2.4V-5.5V | 8-bit Microcontrollers - MCU 64KB 20MHz 2.4V-5.5V |
| Manufacturer | Microchip | Microchip | Microchip |
| Product Category | 8-bit Microcontrollers - MCU | 8-bit Microcontrollers - MCU | 8-bit Microcontrollers - MCU |
| RoHS | Y | Y | Y |
| Mounting Style | SMD/SMT | SMD/SMT | SMD/SMT |
| Package / Case | LQFP-44 | PLCC-44 | TQFP-44 |
| Core | 8051 | 8051 | 8051 |
| Data Bus Width | 8 bit | 8 bit | 8 bit |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz |
| Program Memory Size | 64 kB | 64 kB | 64 kB |
| Data RAM Size | 2 kB | 256 B | 2 kB |
| ADC Resolution | 10 bit | 10 bit | 10 bit |
| Number of I/Os | 36 I/O | 40 I/O | 36 I/O |
| Operating Supply Voltage | 2.4 V to 5.5 V | 2.4 V to 5.5 V | 2.4 V to 5.5 V |
| Minimum Operating Temperature | - 40 C | - 40 C | - 40 C |
| Maximum Operating Temperature | + 85 C | + 85 C | + 85 C |
| Packaging | Tray | Tube | Tray |
| Height | 1.6 mm | 4.57 mm | 1.2 mm |
| Length | 12 mm | 17.65 mm | 12 mm |
| Program Memory Type | Flash | Flash | Flash |
| Width | 12 mm | 17.65 mm | 12 mm |
| Brand | Microchip Technology / Atmel | Microchip Technology / Atmel | Microchip Technology / Atmel |
| Data RAM Type | ERAM | SRAM | ERAM |
| Data ROM Size | 4 kB | 4 kB | 4 kB |
| Data ROM Type | EEPROM | EEPROM | EEPROM |
| Interface Type | 2-Wire, SPI, UART | I2C, SPI, UART | 2-Wire, SPI, UART |
| Moisture Sensitive | Yes | Yes | Yes |
| Number of ADC Channels | 8 | 8 Channel | 8 |
| Number of Timers/Counters | 3 Timer | 3 Timer | 3 Timer |
| Processor Series | AT89x | AT89LP51ED2 | AT89x |
| Product Type | 8-bit Microcontrollers - MCU | 8-bit Microcontrollers - MCU | 8-bit Microcontrollers - MCU |
| Factory Pack Quantity | 160 | 27 | 160 |
| Subcategory | Microcontrollers - MCU | Microcontrollers - MCU | Microcontrollers - MCU |
| Supply Voltage Max | 5.5 V | 5.5 V | 5.5 V |
| Supply Voltage Min | 2.4 V | 2.4 V | 2.4 V |
| Unit Weight | 0.012561 oz | 0.084185 oz | 0.009640 oz |
| Product | - | MCU | - |
| Analog Supply Voltage | - | - | - |
| DAC Resolution | - | - | - |
| I/O Voltage | - | - | - |
| Watchdog Timers | - | Watchdog Timer | - |