AT89S51-24PC Equivalent & Substitute Parts

Part Overview

The AT89S51-24PC is an 8-bit microcontroller from Microchip Technology's 89S series, featuring 4KB of FLASH program memory and operating at 24MHz. This device is classified as obsolete, which necessitates identification of functionally equivalent alternatives for ongoing design support and component procurement. The AT89S51-24PC is packaged in a 40-DIP through-hole configuration and operates within a 4V to 5.5V supply voltage range.

Substiute Parts

AT89S51-24PC

Microchip TechnologyIn Stock: 2549AT89S51-24PC Datasheet

Current PartRFQ

AT89S51-24PU

Microchip TechnologyIn Stock: 11094AT89S51-24PU Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AT89S51-24PC is determined by strict equivalence across the following critical parameters:

• Core processor architecture (8051)
• Core size (8-Bit)
• Operating frequency (24MHz)
• Program memory capacity and type (4KB FLASH)
• RAM capacity (128 x 8)
• Supply voltage range (4V ~ 5.5V)
• I/O count (32 pins)
• Connectivity interface (UART/USART)
• Peripheral features (WDT)
• Package type and pin count (40-DIP)
• Mounting configuration (Through Hole)

The AT89S51-24PU meets all these criteria and is therefore a direct functional equivalent. The primary distinction between these parts lies in product status, packaging format, and operating temperature range.

Parameter Comparison

Engineering Selection Recommendations

The AT89S51-24PU is the direct functional equivalent to the AT89S51-24PC across all electrical and mechanical specifications. Selection between these parts should be based on the following factors:

The AT89S51-24PC is obsolete and carries RoHS non-compliance status. The AT89S51-24PU is actively manufactured, ROHS3 compliant, and offers an extended operating temperature range of -40°C to 85°C compared to the 0°C to 70°C range of the AT89S51-24PC. For new designs or ongoing production requiring regulatory compliance, the AT89S51-24PU is the appropriate selection. For legacy system maintenance where the original operating temperature range is sufficient, the AT89S51-24PC may be used if inventory is available, though long-term availability is not assured due to obsolete status.

Frequently Asked Questions (FAQ)

Q: Are AT89S51-24PC and AT89S51-24PU pin-for-pin compatible?

A: Yes. Both devices use the 40-DIP package with identical pin assignments, electrical characteristics, and functional specifications. Direct substitution on the PCB is possible without circuit modification.

Q: What is the difference between the -24PC and -24PU suffix designations?

A: The suffix indicates packaging format and product status. The -24PC variant is supplied loose and is classified as obsolete. The -24PU variant is supplied in tube packaging and maintains active production status.

Q: Can the AT89S51-24PU be used in applications originally designed for the AT89S51-24PC?

A: Yes. The AT89S51-24PU is functionally equivalent and meets all electrical and mechanical requirements of the AT89S51-24PC. The extended operating temperature range (-40°C to 85°C) of the AT89S51-24PU provides additional environmental capability.

Q: What are the compliance differences between these parts?

A: The AT89S51-24PC is RoHS non-compliant. The AT89S51-24PU is ROHS3 compliant. Both parts are REACH unaffected and classified under ECCN EAR99.

Q: Are there any firmware or software compatibility issues when substituting these parts?

A: No. Both parts implement the identical 8051 core processor architecture and instruction set. Firmware compiled for the AT89S51-24PC will execute identically on the AT89S51-24PU without modification.

Q: What is the inventory status of these parts?

A: The AT89S51-24PC has 2461 pieces in stock. The AT89S51-24PU has 11000 pieces in stock. Given the obsolete status of the AT89S51-24PC, the AT89S51-24PU is recommended for procurement to ensure supply continuity.