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AT89C2051-24SU

MCHPAT89C2051-24SU

Microchip Technology
8051 89C Microcontroller IC 8-Bit 24MHz 2KB (2K x 8) FLASH 20-SOIC
Active6,149 in stock
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Overview

The AT89C2051-24SU 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. It operates at speeds up to 24MHz and includes an integrated analog comparator and direct LED drive capabilities in a compact 20-pin SOIC package. This device provides a cost-effective solution for simple embedded control applications that require a familiar industry-standard instruction set.

Why Choose This Part

The AT89C2051 provides a fully static 24MHz operation that allows for precise power management using Idle and Power-down modes. Its high-current 20mA I/O capability simplifies hardware design by allowing it to drive LEDs and small relays directly without external transistors.

Applications

Simple LED Controllers
Utilizes the integrated direct LED drive outputs and high-current I/O pins for basic display and indicator management.
Analog Signal Monitoring
Leverages the on-chip analog comparator for threshold detection in simple sensor-based control loops.
Legacy System Maintenance
Acts as a drop-in 8051-compatible core for maintaining or upgrading older industrial and consumer designs.
Point-of-Load Interfacing
Serves as a dedicated UART interface or I/O expander for larger host systems via its integrated serial port.

Key Specifications

Speed 24MHz
RAM Size 128 x 8
Core Size 8-Bit
Peripherals LED
Connectivity UART/USART
Mounting Type Surface Mount
Number of I/O 15
Core Processor 8051
Package / Case 20-SOIC (0.295", 7.50mm Width)
Oscillator Type Internal
Program Memory Size 2KB (2K x 8)
Program Memory Type FLASH
Operating Temperature -40degC ~ 85degC (TA)
Supplier Device Package 20-SOIC
Voltage - Supply (Vcc/Vdd) 4V ~ 6V

Getting Started

Development requires an 8051-compatible C compiler such as Keil C51 or SDCC. For hardware debugging and programming, use a standard 8051 parallel programmer or an ISP-compatible tool if using modern variants, ensuring the 4V to 6V supply range is maintained.

AT89C2051-24 Family

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

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