Equivalent & Substitute Parts for 25AA040AT-I/MS

Part Overview

The 25AA040AT-I/MS is a 4Kbit EEPROM memory IC manufactured by Microchip Technology, featuring SPI interface operation at 10 MHz. This non-volatile memory device is designed for applications requiring persistent data storage with low power consumption and wide voltage compatibility (1.8V to 5.5V). The part is currently in active production status with verified programmability through DiGi-Electronics and maintains full RoHS3 compliance.

Equivalent and substitute parts are identified when design requirements permit tolerance of specified parameter variations, such as increased clock frequency, modified voltage supply ranges, or alternative packaging formats, while maintaining core functional compatibility in 4Kbit SPI EEPROM applications.

Substiute Parts

25AA040AT-I/MS

Microchip TechnologyIn Stock: 410625AA040AT-I/MS Datasheet

Current PartRFQ

25AA040A-I/MS

Microchip TechnologyIn Stock: 243225AA040A-I/MS Datasheet

DirectRFQ

M95040-RDW6TP

STMicroelectronicsIn Stock: 16047M95040-RDW6TP Datasheet

MFR RecommendedRFQ

M95040-WDW6TP

STMicroelectronicsIn Stock: 1544M95040-WDW6TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 25AA040AT-I/MS is determined by the following criteria:

Core Functional Requirements (Non-Negotiable):

• Memory capacity: 4Kbit
• Memory organization: 512 x 8
• Interface protocol: SPI
• Write cycle time: 5ms
• Operating temperature range: -40°C ~ 85°C
• Mounting type: Surface Mount
• RoHS3 compliance

Allowable Parameter Variations:

• Clock frequency: May increase from 10 MHz (backward compatible)
• Voltage supply range: May be subset of 1.8V ~ 5.5V (e.g., 2.5V ~ 5.5V)
• Package format: 8-MSOP or 8-TSSOP (both 8-pin configurations)
• Packaging type: Tube, Cut Tape, or Tape & Reel

Substitutes are grouped by manufacturer and clock frequency capability while maintaining identical memory specifications and thermal operating range.

Parameter Comparison

Engineering Selection Recommendations

Direct Equivalent (Same Manufacturer): The 25AA040A-I/MS is a direct equivalent from Microchip Technology with identical electrical specifications, memory organization, and clock frequency. This part maintains verified programmability status and is suitable for direct replacement in existing designs without modification.

Cross-Manufacturer Substitutes (STMicroelectronics M95040 Series): The M95040-RDW6TP and M95040-WDW6TP are functionally compatible substitutes offering doubled clock frequency (20 MHz) while maintaining all core memory specifications. Both parts are RoHS3 compliant and operate within the required temperature range.

• M95040-WDW6TP is preferred for new designs due to verified DiGi-Electronics programmability status.
• M95040-RDW6TP is available in higher inventory quantity but lacks programmability verification.
• Both M95040 variants use 8-TSSOP packaging (0.173" width) versus the 8-MSOP packaging (0.118" width) of the original part, requiring PCB layout adjustment.

Voltage Supply Consideration: The M95040-WDW6TP operates within a reduced voltage range (2.5V ~ 5.5V) compared to the 25AA040AT-I/MS (1.8V ~ 5.5V). This substitution is valid only for applications where the minimum supply voltage does not fall below 2.5V.

All substitute parts maintain active production status and full RoHS3 compliance.

Frequently Asked Questions (FAQ)

Q: Can the 25AA040A-I/MS replace the 25AA040AT-I/MS without any design changes? A: Yes. The 25AA040A-I/MS is a direct equivalent with identical electrical specifications, memory capacity, clock frequency, and packaging. No design modifications are required.

Q: What are the key differences between the Microchip 25AA040 series and the STMicroelectronics M95040 series? A: The primary difference is clock frequency: M95040 devices operate at 20 MHz versus 10 MHz for the 25AA040 series. Both maintain identical 4Kbit capacity, 512 x 8 organization, and 5ms write cycle time. The M95040 series uses 8-TSSOP packaging (0.173" width) while the 25AA040 uses 8-MSOP packaging (0.118" width), requiring PCB layout changes.

Q: Is the M95040-RDW6TP suitable for production designs? A: The M95040-RDW6TP meets all functional and compliance requirements. However, it lacks verified programmability status through DiGi-Electronics. The M95040-WDW6TP is recommended for production applications due to verified programmability certification.

Q: Can I use the M95040-WDW6TP in a design requiring 1.8V minimum supply voltage? A: No. The M95040-WDW6TP operates within 2.5V ~ 5.5V range and is not suitable for applications requiring 1.8V minimum supply voltage. The 25AA040AT-I/MS or 25AA040A-I/MS must be used for 1.8V operation.

Q: What packaging changes occur when switching from 25AA040AT-I/MS to M95040 series? A: The 25AA040AT-I/MS uses 8-MSOP packaging (0.118" width, 3.00mm), while M95040 devices use 8-TSSOP packaging (0.173" width, 4.40mm). PCB footprint modification is required. Both are 8-pin surface mount packages with identical pin functionality.

Q: Are all substitute parts RoHS3 compliant? A: Yes. All listed substitute parts (25AA040A-I/MS, M95040-RDW6TP, M95040-WDW6TP) maintain ROHS3 compliance and are suitable for applications with RoHS requirements.