AT25DF021-SSH-B Equivalent & Substitute Parts

Part Overview

The AT25DF021-SSH-B is a 2Mbit Serial Peripheral Interface (SPI) FLASH memory IC manufactured by Microchip Technology, packaged in 8-SOIC form factor. This device operates at 70 MHz clock frequency with a supply voltage range of 2.7V to 3.6V and is rated for -40°C to 85°C operating temperature. The product is currently classified as obsolete, making equivalent substitute parts necessary for ongoing design support and procurement continuity.

Substiute Parts

AT25DF021-SSH-B

Microchip TechnologyIn Stock: 5152AT25DF021-SSH-B Datasheet

Current PartRFQ

LE25U20AMB-AH

onsemiIn Stock: 10365LE25U20AMB-AH Datasheet

MFR RecommendedRFQ

W25X20CLSNIG

Winbond ElectronicsIn Stock: 55503W25X20CLSNIG Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the AT25DF021-SSH-B is determined by the following critical parameters:

• Memory capacity: 2Mbit (256K x 8 organization)
• Interface protocol: SPI
• Package form factor: 8-SOIC with 0.154" width (3.90mm)
• Supply voltage compatibility: Minimum 2.7V support required
• Operating temperature range: -40°C to 85°C minimum
• RoHS3 compliance status

The two identified substitute parts meet these core substitution criteria. Variations in clock frequency (70 MHz vs. 30 MHz or 104 MHz), write cycle time, and voltage supply upper limits do not disqualify substitution when the above parameters align.

Parameter Comparison

Engineering Selection Recommendations

Both substitute parts are ROHS3 compliant and maintain the same 8-SOIC package footprint as the AT25DF021-SSH-B, ensuring mechanical and electrical compatibility at the board level.

The LE25U20AMB-AH (onsemi) operates at 30 MHz clock frequency, which is lower than the original part's 70 MHz specification. This substitute is suitable for applications where the reduced clock speed does not impact system performance requirements. The part is currently in active production status with high inventory availability.

The W25X20CLSNIG (Winbond Electronics) operates at 104 MHz clock frequency, exceeding the original part's 70 MHz specification. This substitute provides enhanced performance headroom and is verified as programmable by DiGi-Electronics. The part is in active production status with the highest inventory availability among all options.

Both substitutes support the full -40°C to 85°C operating temperature range and maintain SPI interface compatibility. The voltage supply range for both substitutes extends to 2.3V minimum, providing broader supply voltage tolerance compared to the original 2.7V minimum specification.

Frequently Asked Questions (FAQ)

Q: Can the LE25U20AMB-AH be used as a direct replacement for the AT25DF021-SSH-B?

A: Yes. Both parts share identical memory capacity (2Mbit), organization (256K x 8), SPI interface, 8-SOIC package form factor, and operating temperature range. The 30 MHz clock frequency of the LE25U20AMB-AH is lower than the original 70 MHz, so compatibility depends on your application's maximum clock speed requirement.

Q: What are the advantages of the W25X20CLSNIG substitute?

A: The W25X20CLSNIG operates at 104 MHz, providing higher clock frequency performance than the original AT25DF021-SSH-B. It maintains identical package geometry, memory capacity, and interface protocol. The part is verified as programmable and has the highest inventory availability.

Q: Are there any package differences between the main part and substitutes?

A: All three parts use the 8-SOIC package with 0.154" width (3.90mm). The package footprint and pin configuration are identical, allowing direct PCB-level substitution without layout modifications.

Q: Do the substitute parts meet RoHS compliance requirements?

A: Yes. Both the LE25U20AMB-AH and W25X20CLSNIG are ROHS3 compliant, matching the compliance status of the AT25DF021-SSH-B.

Q: What is the impact of the lower 30 MHz clock frequency in the LE25U20AMB-AH?

A: The reduced clock frequency limits the maximum data transfer rate. Select this substitute only if your system design can operate at or below 30 MHz SPI clock speeds. If your application requires higher clock frequencies, the W25X20CLSNIG at 104 MHz is the appropriate choice.

Q: Can I use the W25X20CLSNIG in a design originally specified for 70 MHz operation?

A: Yes. The W25X20CLSNIG's 104 MHz clock frequency exceeds the original 70 MHz specification, ensuring compatibility with designs expecting up to 70 MHz operation. The higher clock speed provides additional performance margin.