AT25256W-10SC-2.7 Equivalent & Substitute Parts

Part Overview

The AT25256W-10SC-2.7 is a 256Kbit EEPROM memory IC manufactured by Microchip Technology, featuring SPI interface operation at 3 MHz. This device is classified as obsolete, which necessitates identification of functionally equivalent alternatives for new designs and ongoing production requirements. The part operates across a supply voltage range of 2.7V to 5.5V and is housed in an 8-SOIC package suitable for surface mount applications.

Substiute Parts

AT25256W-10SC-2.7

Microchip TechnologyIn Stock: 1131AT25256W-10SC-2.7 Datasheet

Current PartRFQ

25AA256-E/SM

Microchip TechnologyIn Stock: 143325AA256-E/SM Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AT25256W-10SC-2.7 is determined by the following critical parameters:

• Memory capacity (256Kbit) and organization (32K x 8)
• SPI serial interface protocol
• Package form factor (8-SOIC, 0.209" width, 5.30mm)
• Write cycle time (5ms)
• Supply voltage compatibility

The 25AA256-E/SM qualifies as a direct substitute based on matching memory size, organization, SPI interface, and identical package dimensions. While this substitute offers enhanced specifications in clock frequency (10 MHz versus 3 MHz) and extended operating temperature range (-40°C to 125°C versus 0°C to 70°C), these represent functional improvements that maintain backward compatibility with the original design requirements.

Parameter Comparison

Engineering Selection Recommendations

The 25AA256-E/SM is the qualified substitute for AT25256W-10SC-2.7 applications. Selection of this alternative is supported by:

• Active product status, ensuring long-term availability and supply chain continuity
• ROHS3 compliance, meeting current environmental and regulatory requirements
• Verified programmability status, confirming functional compatibility
• Identical package footprint and pinout, enabling direct board-level substitution
• Backward-compatible SPI protocol implementation
• Extended supply voltage range (1.8V minimum) providing broader system integration flexibility
• Enhanced clock frequency capability (10 MHz) supporting higher data throughput without design modification

Frequently Asked Questions (FAQ)

Q: Can the 25AA256-E/SM directly replace the AT25256W-10SC-2.7 on existing PCBs?

A: Yes. Both devices share identical 8-SOIC package dimensions (0.209" width, 5.30mm), pinout configuration, and SPI interface protocol. No PCB modifications are required.

Q: What are the key differences between these parts?

A: The 25AA256-E/SM operates at higher clock frequency (10 MHz versus 3 MHz), supports lower minimum supply voltage (1.8V versus 2.7V), extends operating temperature range (-40°C to 125°C versus 0°C to 70°C), and maintains active product status with ROHS3 compliance.

Q: Are there compatibility concerns with the higher clock frequency of the substitute?

A: No. The substitute's 10 MHz capability is a performance enhancement. Existing designs operating at 3 MHz will function without modification, as the SPI interface remains fully compatible.

Q: Does the extended temperature range of the 25AA256-E/SM affect its use in standard applications?

A: No. Extended temperature range represents an operational advantage. Applications requiring only 0°C to 70°C operation will function normally within this broader specification.

Q: What is the significance of ROHS3 compliance on the substitute part?

A: ROHS3 compliance indicates conformance to current environmental regulations and is required for many commercial and industrial applications. The original AT25256W-10SC-2.7 is RoHS non-compliant.

Q: Is the 25AA256-E/SM suitable for new design implementations?

A: Yes. The active product status, regulatory compliance, and verified programmability make this part appropriate for new designs requiring 256Kbit SPI EEPROM functionality.