AT25SF081-SHD-B Equivalent & Substitute Parts

Part Overview

The AT25SF081-SHD-B is an 8Mbit NOR Flash memory IC manufactured by Renesas Electronics Corporation, featuring SPI and Quad I/O interface capability in an 8-SOIC package. This part is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement continuity. The device operates across a 2.5V to 3.6V supply range with a maximum clock frequency of 104 MHz, suitable for embedded systems requiring non-volatile memory storage with quad-mode read acceleration.

Key Parameters

Parameter	Value
Memory Size	8Mbit
Memory Format	FLASH - NOR
Memory Organization	1M x 8
Memory Interface	SPI - Quad I/O
Clock Frequency	104 MHz
Voltage Supply Range	2.5V ~ 3.6V
Operating Temperature	-40°C ~ 85°C
Package Type	8-SOIC (0.209", 5.30mm Width)
Mounting Type	Surface Mount
RoHS Status	ROHS3 Compliant

Substitute Part Grouping Explanation

Substitution eligibility for the AT25SF081-SHD-B is determined by the following critical parameters:

Memory Capacity: Must be 8Mbit
Memory Technology: Must be FLASH - NOR
Memory Interface: Must support SPI - Quad I/O
Package: Must be 8-SOIC with 0.209" (5.30mm) width
Voltage Compatibility: Supply voltage range must overlap or encompass the original 2.5V ~ 3.6V range
Operating Temperature: Must support -40°C ~ 85°C minimum
Mounting Type: Must be Surface Mount

Substitute parts are grouped into two categories based on voltage supply compatibility and product status:

Category A - Direct Voltage Compatible (Active Status): AT25SF081B-SHD-B and AT25SF081B-SHB-B maintain the original 2.5V ~ 3.6V supply range with enhanced clock frequency and improved write cycle times.

Category B - Extended Voltage Range (Active Status): AT25FF081A-SHN-B offers extended lower voltage operation (1.65V ~ 3.6V) with higher clock frequency (133 MHz) but different memory organization (2M x 4).

Category C - Reduced Performance Alternative: W25Q80DVSSIG provides active product status with verified programmability and high inventory availability, though with narrower voltage range (2.7V ~ 3.6V).

Category D - Limited Compatibility: LE25U81AFDTWG operates at reduced clock frequency (40 MHz) with narrower voltage range (2.3V ~ 2.7V) and different package dimensions (8-VSOIC, 0.154" width), limiting direct substitution suitability.

Parameter Comparison

Parameter	AT25SF081-SHD-B (Main)	AT25FF081A-SHN-B	AT25SF081B-SHB-B	AT25SF081B-SHD-B	W25Q80DVSSIG	LE25U81AFDTWG
Manufacturer	Renesas	Renesas	Renesas	Renesas	Winbond	onsemi
Memory Size	8Mbit	8Mbit	8Mbit	8Mbit	8Mbit	8Mbit
Memory Organization	1M x 8	2M x 4	1M x 8	1M x 8	1M x 8	1M x 8
Memory Interface	SPI - Quad I/O	SPI - Quad I/O	SPI - Quad I/O	SPI - Quad I/O	SPI - Quad I/O	SPI
Clock Frequency	104 MHz	133 MHz	108 MHz	108 MHz	104 MHz	40 MHz
Voltage Supply Range	2.5V ~ 3.6V	1.65V ~ 3.6V	2.7V ~ 3.6V	2.5V ~ 3.6V	2.7V ~ 3.6V	2.3V ~ 2.7V
Operating Temperature	-40°C ~ 85°C	-40°C ~ 85°C	-40°C ~ 85°C	-40°C ~ 85°C	-40°C ~ 85°C	-40°C ~ 85°C
Package / Case	8-SOIC (0.209", 5.30mm)	8-SOIC (0.209", 5.30mm)	8-SOIC (0.209", 5.30mm)	8-SOIC (0.209", 5.30mm)	8-SOIC (0.209", 5.30mm)	8-VSOIC (0.154", 3.90mm)
Product Status	Obsolete	Active	Active	Active	Active	Active
RoHS Status	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant
Inventory Status	2300 Pcs	1040 Pcs	1053 Pcs	675 Pcs	133980 Pcs	760 Pcs

Engineering Selection Recommendations

AT25SF081B-SHD-B is the primary substitute for direct replacement. It maintains identical voltage supply range (2.5V ~ 3.6V), memory organization (1M x 8), and package dimensions while offering active product status and improved write cycle performance. This part provides the highest compatibility with existing designs without requiring voltage regulation adjustments.

AT25SF081B-SHB-B serves as an alternative Renesas solution with active status. The minimum supply voltage increases to 2.7V, requiring verification that system power rails do not drop below this threshold during operation. Clock frequency and write cycle times are equivalent to the AT25SF081B-SHD-B variant.

AT25FF081A-SHN-B is suitable for applications requiring extended lower voltage operation (1.65V ~ 3.6V) and higher clock frequency (133 MHz). The memory organization differs (2M x 4 versus 1M x 8), necessitating firmware verification to confirm compatibility with existing memory access patterns. This part is recommended only when lower voltage operation is a design requirement.

W25Q80DVSSIG offers the highest inventory availability (133980 units) and verified programmability status. The minimum supply voltage is 2.7V. This part is recommended for new designs or high-volume procurement where supply chain continuity is prioritized. Winbond SpiFlash® series compatibility should be verified against application firmware.

LE25U81AFDTWG is not recommended as a primary substitute due to multiple incompatibilities: reduced clock frequency (40 MHz), narrower voltage range (2.3V ~ 2.7V), different package dimensions (8-VSOIC, 0.154" width), and single SPI interface without Quad I/O support. This part may only be considered if system constraints explicitly require the narrower package width and lower voltage operation.

Frequently Asked Questions (FAQ)

Q: Can AT25SF081B-SHD-B be used as a direct drop-in replacement for AT25SF081-SHD-B?

A: Yes. Both parts share identical voltage supply range (2.5V ~ 3.6V), memory organization (1M x 8), package type (8-SOIC, 0.209" width), and operating temperature range (-40°C ~ 85°C). The AT25SF081B-SHD-B is active status, making it the recommended substitute for the obsolete AT25SF081-SHD-B.

Q: What is the difference between AT25SF081B-SHD-B and AT25SF081B-SHB-B?

A: Both parts are functionally equivalent with identical clock frequency (108 MHz) and write cycle times. The primary difference is minimum supply voltage: AT25SF081B-SHD-B operates from 2.5V, while AT25SF081B-SHB-B requires minimum 2.7V. Select based on your system's minimum power rail voltage.

Q: Why does AT25FF081A-SHN-B have different memory organization (2M x 4 versus 1M x 8)?

A: AT25FF081A-SHN-B uses a different internal architecture optimized for higher clock frequency (133 MHz) and extended voltage range (1.65V ~ 3.6V). The 2M x 4 organization means data is organized as 2 million 4-bit words instead of 1 million 8-bit words. Firmware must be verified to confirm compatibility with this organization before substitution.

Q: Is W25Q80DVSSIG compatible with designs using AT25SF081-SHD-B?

A: W25Q80DVSSIG is electrically compatible in terms of memory capacity (8Mbit), interface (SPI - Quad I/O), package (8-SOIC, 0.209" width), and operating temperature. However, minimum supply voltage is 2.7V (versus 2.5V for the original). Verify your system power rails remain above 2.7V. Firmware compatibility with Winbond SpiFlash® series should be confirmed.

Q: Why is LE25U81AFDTWG not recommended as a substitute?

A: LE25U81AFDTWG has multiple incompatibilities: clock frequency is reduced to 40 MHz (versus 104 MHz), voltage range is narrower (2.3V ~ 2.7V), package dimensions differ (8-VSOIC, 0.154" width versus 8-SOIC, 0.209" width), and it lacks Quad I/O support (SPI only). These differences make it unsuitable for direct substitution.

Q: What inventory considerations should guide part selection?

A: W25Q80DVSSIG has significantly higher inventory (133980 units) compared to Renesas alternatives (675-1053 units). For high-volume production or long-term supply chain security, W25Q80DVSSIG is preferred. For immediate replacement of existing designs, AT25SF081B-SHD-B is recommended despite lower inventory levels.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. All listed substitute parts (AT25FF081A-SHN-B, AT25SF081B-SHB-B, AT25SF081B-SHD-B, W25Q80DVSSIG, and LE25U81AFDTWG) are ROHS3 compliant, matching the original AT25SF081-SHD-B compliance status.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message