25AA640A-E/ST EEPROM Memory IC Equivalent & Substitute Parts

Part Overview

The 25AA640A-E/ST is a 64Kbit Serial Peripheral Interface (SPI) EEPROM memory IC manufactured by Microchip Technology. This non-volatile memory device operates across a wide supply voltage range of 1.8V to 5.5V and supports operating temperatures from -40°C to 125°C. The component is housed in an 8-TSSOP surface mount package and is currently in active production status with ROHS3 compliance. Substitute parts are identified when equivalent memory capacity, interface protocol, package form factor, and electrical specifications align with application requirements.

Substiute Parts

25AA640A-E/ST

Microchip TechnologyIn Stock: 194425AA640A-E/ST Datasheet

Current PartRFQ

M95640-DRDW3TP/K

STMicroelectronicsIn Stock: 17613M95640-DRDW3TP/K Datasheet

MFR RecommendedRFQ

R1EX25064ATA00I#S0

Renesas Electronics CorporationIn Stock: 2370R1EX25064ATA00I#S0 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 25AA640A-E/ST are qualified based on the following critical parameters:

• Memory Capacity: 64Kbit (8K x 8 organization) — exact match required
• Interface Protocol: SPI — no alternative protocols acceptable
• Package Form Factor: 8-TSSOP with 0.173" width and 4.40mm dimensions — mechanical compatibility mandatory
• Supply Voltage: 1.8V ~ 5.5V minimum range — substitutes must support this range
• Operating Temperature: Minimum -40°C to 125°C — substitutes meeting or exceeding this range are acceptable
• Memory Type: Non-volatile EEPROM technology — functional equivalence required
• Compliance: ROHS3 compliance — regulatory alignment required

The identified substitute parts meet all mandatory electrical and mechanical criteria for direct component replacement in applications designed for the 25AA640A-E/ST.

Parameter Comparison

Engineering Selection Recommendations

M95640-DRDW3TP/K (STMicroelectronics): This substitute offers enhanced performance characteristics with a 20 MHz clock frequency and 4ms write cycle time, both superior to the primary part. The device maintains full voltage and temperature compatibility and includes AEC-Q100 automotive qualification. This part is suitable for applications requiring higher data throughput or automotive-grade reliability.

R1EX25064ATA00I#S0 (Renesas Electronics): This substitute maintains electrical equivalence with a 5 MHz clock frequency and 5ms write cycle time, matching the primary part's write performance. The operating temperature range is limited to -40°C to 85°C, which is narrower than the primary part. This substitute is appropriate for applications operating within the reduced temperature specification.

All three parts maintain identical memory capacity, SPI interface protocol, 8-TSSOP package dimensions, and 1.8V to 5.5V supply voltage compatibility. Selection between substitutes depends on specific application requirements for clock frequency, write cycle performance, and operating temperature range.

Frequently Asked Questions (FAQ)

Q: Can the M95640-DRDW3TP/K replace the 25AA640A-E/ST in all applications?

A: The M95640-DRDW3TP/K is electrically and mechanically compatible with the 25AA640A-E/ST. The higher clock frequency (20 MHz vs. 10 MHz) and faster write cycle time (4ms vs. 5ms) are backward compatible with designs expecting the primary part's specifications. No design modifications are required.

Q: What is the key limitation of the R1EX25064ATA00I#S0 substitute?

A: The R1EX25064ATA00I#S0 has a reduced operating temperature range of -40°C to 85°C compared to the primary part's -40°C to 125°C range. This substitute is not suitable for applications requiring operation above 85°C.

Q: Are all three parts pin-compatible?

A: Yes. All three parts use the 8-TSSOP package with identical 0.173" width and 4.40mm dimensions. Pin configuration and SPI interface protocol are equivalent across all parts.

Q: Do all substitute parts meet RoHS compliance requirements?

A: Yes. The 25AA640A-E/ST, M95640-DRDW3TP/K, and R1EX25064ATA00I#S0 are all ROHS3 compliant.

Q: Which substitute offers the best performance?

A: The M95640-DRDW3TP/K provides the highest performance with 20 MHz clock frequency and 4ms write cycle time. Selection should be based on specific application requirements rather than performance alone.