AT25640-10PI-1.8 Equivalent & Substitute Parts

Part Overview

The AT25640-10PI-1.8 is a 64Kbit EEPROM memory IC with SPI interface operating at 3 MHz, manufactured by Microchip Technology. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity. The part operates across a 1.8V to 3.6V supply range in an 8-DIP through-hole package.

Substiute Parts

AT25640-10PI-1.8

Microchip TechnologyIn Stock: 1042AT25640-10PI-1.8 Datasheet

Current PartRFQ

25AA640A-I/P

Microchip TechnologyIn Stock: 378225AA640A-I/P Datasheet

DirectRFQ

25AA640-I/P

Microchip TechnologyIn Stock: 110325AA640-I/P Datasheet

MFR RecommendedRFQ

25AA640-I/SN

Microchip TechnologyIn Stock: 210225AA640-I/SN Datasheet

MFR RecommendedRFQ

25LC640-I/P

Microchip TechnologyIn Stock: 253325LC640-I/P Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the AT25640-10PI-1.8 is determined by the following critical parameters:

• Memory Capacity: All substitutes maintain 64Kbit capacity with 8K x 8 organization
• Interface Protocol: SPI interface is mandatory for functional compatibility
• Package Compatibility: Primary substitutes use 8-DIP through-hole packaging; surface-mount alternatives available
• Supply Voltage: Substitutes must support operation within or encompass the original 1.8V ~ 3.6V range
• Operating Temperature: All substitutes maintain -40°C ~ 85°C range
• Write Cycle Time: 5ms specification is consistent across all parts

Substitutes are grouped by clock frequency capability and voltage supply range, as these parameters determine operational compatibility in existing circuit designs.

Parameter Comparison

Engineering Selection Recommendations

25AA640A-I/P: This part operates at 10 MHz clock frequency with expanded voltage range (1.8V ~ 5.5V), providing higher performance capability than the original. It maintains 8-DIP through-hole packaging and is ROHS3 compliant with active product status. This substitute is suitable for designs requiring increased clock speed while maintaining the same package footprint.

25AA640-I/P: Operating at 1 MHz with 1.8V ~ 5.5V supply range, this part is ROHS3 compliant and verified for programmability. It provides conservative clock frequency operation in an 8-DIP through-hole package. This substitute is appropriate for designs where lower clock speeds are acceptable and compliance with modern environmental standards is required.

25AA640-I/SN: This variant maintains the same electrical specifications as 25AA640-I/P but uses 8-SOIC surface-mount packaging. It is ROHS3 compliant and verified for programmability. This substitute is applicable only to designs using surface-mount assembly processes.

25LC640-I/P: Operating at 2 MHz with 2.5V ~ 5.5V supply range, this part is ROHS3 compliant and verified for programmability. It provides intermediate clock frequency operation in 8-DIP through-hole packaging. This substitute is suitable for designs operating above 2.5V where moderate clock speed is required.

All substitutes are manufactured by Microchip Technology and maintain functional compatibility through identical memory capacity, organization, and SPI interface protocol.

Frequently Asked Questions (FAQ)

Q: Can 25AA640A-I/P directly replace AT25640-10PI-1.8 in existing designs?

A: Yes, provided the circuit operates within the 1.8V ~ 3.6V range. The 25AA640A-I/P supports this voltage range and maintains identical memory capacity, organization, SPI interface, and 8-DIP package. The higher 10 MHz clock frequency is backward compatible with designs using 3 MHz operation.

Q: What is the primary difference between 25AA640-I/P and 25LC640-I/P?

A: The primary differences are clock frequency (1 MHz vs. 2 MHz) and minimum supply voltage (1.8V vs. 2.5V). Both maintain 64Kbit capacity, SPI interface, and 8-DIP through-hole packaging. Selection depends on circuit voltage requirements and timing constraints.

Q: Is 25AA640-I/SN compatible with through-hole PCB designs?

A: No. The 25AA640-I/SN uses 8-SOIC surface-mount packaging and is not compatible with through-hole PCB layouts. Use 25AA640-I/P, 25AA640A-I/P, or 25LC640-I/P for through-hole applications.

Q: Why is the original AT25640-10PI-1.8 marked as obsolete?

A: The AT25640-10PI-1.8 is obsolete and no longer in active production. The listed substitutes are active products from Microchip Technology that provide equivalent or enhanced functionality with modern compliance certifications.

Q: Are all substitutes ROHS3 compliant?

A: Yes. All four substitute parts are ROHS3 compliant, whereas the original AT25640-10PI-1.8 is non-compliant. This compliance improvement is a key advantage of transitioning to substitute parts.

Q: What clock frequency should I select for my application?

A: Clock frequency selection depends on your circuit timing requirements. The 25AA640A-I/P (10 MHz) provides maximum speed capability. The 25LC640-I/P (2 MHz) and 25AA640-I/P (1 MHz) provide lower-speed alternatives. All are backward compatible with designs originally using 3 MHz operation.