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AT89C2051-24PU

MCHPAT89C2051-24PU

Microchip Technology
8051 89C Microcontroller IC 8-Bit 24MHz 2KB (2K x 8) FLASH 20-PDIP
Active4,237 in stock
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Overview

The AT89C2051-24PU is a low-voltage, high-performance 8-bit microcontroller based on the MCS-51 architecture, featuring 2KB of Flash memory and 128 bytes of RAM. This 20-pin device provides a compact solution for legacy 8051 applications that require a smaller physical footprint than the traditional 40-pin DIP. It includes a built-in analog comparator and direct LED drive capability, making it well-suited for simple control and monitoring tasks.

Why Choose This Part

The primary advantage is the industry-standard MCS-51 core, which allows engineers to leverage a massive ecosystem of existing code and compilers. It supports a wide operating voltage range of 4V to 6V and features a 24MHz clock speed, offering reliable performance for classic embedded tasks in a through-hole 20-PDIP package.

Applications

Direct LED Control
Utilizing high-current I/O pins to drive LED displays and status indicators without external transistors.
Simple Sensor Monitoring
Integrating the on-chip analog comparator for threshold detection in temperature or light-sensing circuits.
Legacy 8051 System Miniaturization
Porting existing MCS-51 assembly or C code to a 20-pin package to reduce PCB area.
Serial Communication Bridges
Using the hardware UART to manage low-speed data transfer between sensors and host controllers.

Key Specifications

Speed 24MHz
RAM Size 128 x 8
Core Size 8-Bit
Peripherals LED
Connectivity UART/USART
Mounting Type Through Hole
Number of I/O 15
Core Processor 8051
Package / Case 20-DIP (0.300", 7.62mm)
Oscillator Type Internal
Program Memory Size 2KB (2K x 8)
Program Memory Type FLASH
Operating Temperature -40degC ~ 85degC (TA)
Supplier Device Package 20-PDIP
Voltage - Supply (Vcc/Vdd) 4V ~ 6V

Getting Started

To develop for this MCU, you can use the Keil C51 development tools or the SDCC open-source compiler. Programming requires a dedicated high-voltage programmer that supports the AT89C series protocol, as this device does not support In-System Programming (ISP) via SPI like newer AT89S variants.

AT89C2051-24 Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number Package Stock
AT89C2051-24PU (this part) DIP-20 4,237
AT89C2051-24SU SOIC-20 6,149

Also Consider

ATtiny2313 MCHPMicrochip Technology - A more modern 20-pin AVR-based alternative with similar I/O count, higher code efficiency, and modern ISP programming support.
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