25LC128-E/SM EEPROM Memory IC Equivalent & Substitute Parts

Part Overview

The 25LC128-E/SM is a 128Kbit Serial Peripheral Interface (SPI) EEPROM memory IC manufactured by Microchip Technology. This non-volatile memory device operates at 10 MHz clock frequency with a supply voltage range of 2.5V to 5.5V and is housed in an 8-SOIJ surface mount package. The device is currently in active product status with 724 units in stock.

Substitute parts are necessary when the original 25LC128-E/SM becomes unavailable, when alternative packaging formats are required for manufacturing processes, or when enhanced performance specifications (such as higher clock frequency or extended voltage ranges) are needed for system optimization.

Key Parameters

Parameter	Value
Memory Size	128Kbit
Memory Organization	16K x 8
Memory Interface	SPI
Clock Frequency	10 MHz
Write Cycle Time	5ms
Voltage Supply Range	2.5V ~ 5.5V
Operating Temperature	-40°C ~ 125°C
Mounting Type	Surface Mount
Package Type	8-SOIJ (0.209", 5.30mm Width)
RoHS Status	ROHS3 Compliant

Substitute Part Grouping Explanation

Substitution of the 25LC128-E/SM is determined by the following critical parameters:

Core Functional Requirements:

Memory capacity: 128Kbit (16K x 8 organization)
Interface protocol: SPI
Write cycle time: 5ms

Electrical Compatibility:

Supply voltage range must encompass or exceed 2.5V ~ 5.5V
Clock frequency: 10 MHz minimum (higher frequencies are backward compatible)
Operating temperature range: -40°C ~ 125°C minimum

Physical Compatibility:

Surface mount technology
Package footprint compatibility (8-pin SOIC/SOIJ variants with similar pin spacing)

Regulatory Compliance:

RoHS3 compliance required
REACH unaffected status

Substitute parts are grouped into two categories: direct functional equivalents with identical or superior electrical specifications, and package-variant alternatives that maintain electrical compatibility while offering different form factors for manufacturing flexibility.

Parameter Comparison

Part Number	Manufacturer	Memory Size	Clock Frequency	Voltage Supply	Operating Temp	Package Type	Product Status
25LC128-E/SM	Microchip Technology	128Kbit	10 MHz	2.5V ~ 5.5V	-40°C ~ 125°C	8-SOIJ (5.30mm)	Active
AT25128B-SSHL-B	Microchip Technology	128Kbit	20 MHz	1.8V ~ 5.5V	-40°C ~ 85°C	8-SOIC (3.90mm)	Active
AT25128B-SSHL-T	Microchip Technology	128Kbit	20 MHz	1.8V ~ 5.5V	-40°C ~ 85°C	8-SOIC (3.90mm)	Active
BR25S128F-WE2	Rohm Semiconductor	128Kbit	20 MHz	1.7V ~ 5.5V	-40°C ~ 85°C	8-SOP (4.40mm)	Active
CAT25128VI-G	onsemi	128Kbit	20 MHz	1.8V ~ 5.5V	-40°C ~ 85°C	8-SOIC (3.90mm)	Obsolete
CAT25128VI-GT3	onsemi	128Kbit	20 MHz	1.8V ~ 5.5V	-40°C ~ 85°C	8-SOIC (3.90mm)	Active
CAT25128VP2I-GT3	onsemi	128Kbit	20 MHz	1.8V ~ 5.5V	-40°C ~ 85°C	8-TDFN (2x3)	Active
CAT25128XI-T2	onsemi	128Kbit	20 MHz	1.8V ~ 5.5V	-40°C ~ 85°C	8-SOIC (5.30mm)	Active
CAV25128VE-GT3	onsemi	128Kbit	10 MHz	2.5V ~ 5.5V	-40°C ~ 125°C	8-SOIC (3.90mm)	Active
M95128-DFMN6TP	STMicroelectronics	128Kbit	20 MHz	1.7V ~ 5.5V	-40°C ~ 85°C	8-SOIC (3.90mm)	Active
M95128-RMN6TP	STMicroelectronics	128Kbit	20 MHz	1.8V ~ 5.5V	-40°C ~ 85°C	8-SOIC (3.90mm)	Active

Engineering Selection Recommendations

Direct Functional Equivalent (Identical Specifications): CAV25128VE-GT3 (onsemi) matches the 25LC128-E/SM across all critical electrical parameters: 10 MHz clock frequency, 2.5V ~ 5.5V supply voltage range, and -40°C ~ 125°C operating temperature. This part is AEC-Q100 qualified for automotive applications and maintains full compatibility. Product status is active with 24,438 units in stock.

Enhanced Performance Substitutes (Higher Clock Frequency): AT25128B-SSHL-B, AT25128B-SSHL-T, CAT25128VI-GT3, CAT25128XI-T2, M95128-DFMN6TP, and M95128-RMN6TP all operate at 20 MHz, providing doubled clock frequency while maintaining 128Kbit capacity and SPI interface. These parts are suitable for applications where higher data transfer rates are beneficial. All are in active product status with substantial inventory availability.

Voltage Range Consideration: The original 25LC128-E/SM specifies 2.5V ~ 5.5V supply voltage. Most substitute parts operate at 1.7V ~ 1.8V minimum, which is lower than the original specification. Systems designed for the original 2.5V minimum must verify compatibility with substitute parts in low-voltage operating conditions.

Temperature Range Consideration: The original part operates to 125°C. Most substitutes are rated to 85°C maximum. Applications requiring extended temperature operation must select CAV25128VE-GT3, which maintains the -40°C ~ 125°C range.

Package Footprint Compatibility: The original 25LC128-E/SM uses 8-SOIJ (5.30mm width). CAT25128XI-T2 maintains this footprint. Most other substitutes use 8-SOIC (3.90mm width), requiring PCB layout modification. CAT25128VP2I-GT3 uses 8-TDFN (2x3) package, suitable for space-constrained applications.

Product Status: CAT25128VI-G is marked obsolete and should not be selected for new designs. All other listed substitutes maintain active product status.

Frequently Asked Questions (FAQ)

Q: Can I use a 20 MHz substitute part in a circuit designed for the 10 MHz 25LC128-E/SM? A: Yes. Higher clock frequency is backward compatible. A 20 MHz part operates correctly at 10 MHz clock speeds. The system will function identically to the original design.

Q: What is the difference between AT25128B-SSHL-B and AT25128B-SSHL-T? A: Both parts are electrically identical 128Kbit SPI EEPROMs with 20 MHz operation. The difference is packaging format: -B indicates Tube packaging, while -T indicates Cut Tape & Digi-Reel format. Selection depends on manufacturing process requirements.

Q: Is CAV25128VE-GT3 a direct replacement for 25LC128-E/SM? A: CAV25128VE-GT3 is functionally equivalent across all electrical specifications: 128Kbit capacity, 10 MHz clock frequency, 2.5V ~ 5.5V supply voltage, and -40°C ~ 125°C operating temperature. The package footprint differs (8-SOIC 3.90mm vs. 8-SOIJ 5.30mm), requiring PCB layout verification.

Q: Why do most substitutes have lower minimum supply voltage (1.7V ~ 1.8V) than the original (2.5V)? A: Substitute parts offer extended low-voltage operation capability. Systems operating above 2.5V will function identically. Only applications specifically designed for 2.5V minimum operation require verification.

Q: Can I use CAT25128VI-G for a new design? A: No. CAT25128VI-G is marked obsolete and should not be selected for new designs. Use active-status alternatives such as CAT25128VI-GT3 instead.

Q: What package options are available for 128Kbit SPI EEPROM substitutes? A: Available packages include 8-SOIC (0.154" width at 3.90mm, most common), 8-SOIJ (0.209" width at 5.30mm, original package), 8-SOP (0.173" width at 4.40mm), and 8-TDFN (2x3 mm, compact form factor). Package selection depends on PCB layout constraints and manufacturing equipment capabilities.

Q: Are all listed substitutes RoHS3 compliant? A: Yes. All substitute parts listed maintain RoHS3 compliance and REACH unaffected status, matching the original 25LC128-E/SM regulatory requirements.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message