AT25640-10PI-2.7 Equivalent & Substitute Parts

Part Overview

The AT25640-10PI-2.7 is a 64Kbit EEPROM memory IC with SPI interface manufactured by Microchip Technology. This device is classified as obsolete, making equivalent and substitute parts necessary for ongoing system support and new design implementations. The part operates at 3 MHz clock frequency with a supply voltage range of 2.7V to 5.5V and is housed in an 8-DIP through-hole package.

Substiute Parts

AT25640-10PI-2.7

Microchip TechnologyIn Stock: 2357AT25640-10PI-2.7 Datasheet

Current PartRFQ

25AA640A-I/P

Microchip TechnologyIn Stock: 378225AA640A-I/P Datasheet

DirectRFQ

25LC640A-E/P

Microchip TechnologyIn Stock: 128525LC640A-E/P Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the AT25640-10PI-2.7 is determined by the following critical parameters:

• Memory capacity: 64Kbit (8K x 8 organization)
• Interface protocol: SPI
• Package format: 8-DIP through-hole
• Write cycle time: 5ms
• Supply voltage compatibility: minimum 2.7V operation
• Operating temperature range: minimum -40°C to 85°C

The identified substitute parts maintain identical memory capacity, organization, interface, package type, and write cycle time. Both substitute parts operate at higher clock frequencies (10 MHz) and support the required voltage and temperature ranges, making them functionally compatible for applications designed around the AT25640-10PI-2.7.

Parameter Comparison

Engineering Selection Recommendations

Both substitute parts are active products with ROHS3 compliance, providing long-term availability and regulatory alignment compared to the obsolete AT25640-10PI-2.7.

The 25AA640A-I/P supports a lower minimum supply voltage (1.8V) and maintains the same operating temperature range as the original part (-40°C to 85°C).

The 25LC640A-E/P supports an extended operating temperature range (-40°C to 125°C) and a minimum supply voltage of 2.5V, offering thermal performance advantages for applications requiring higher temperature operation.

Both substitute parts operate at 10 MHz, providing improved clock frequency performance over the original 3 MHz specification while maintaining full backward compatibility in SPI protocol, memory capacity, and package footprint.

Frequently Asked Questions (FAQ)

Q: Can the 25AA640A-I/P and 25LC640A-E/P be used interchangeably with the AT25640-10PI-2.7?

A: Yes, both parts are functionally compatible substitutes. They maintain identical memory capacity (64Kbit), organization (8K x 8), SPI interface, write cycle time (5ms), and 8-DIP package format. The primary differences are clock frequency (10 MHz vs. 3 MHz), supply voltage ranges, and operating temperature specifications.

Q: What is the impact of the higher clock frequency in the substitute parts?

A: The substitute parts operate at 10 MHz compared to the original 3 MHz. This higher frequency is backward compatible and does not create functional issues in applications designed for the slower original part. Systems will operate correctly at the faster speed.

Q: Are there supply voltage compatibility concerns?

A: The 25AA640A-I/P supports 1.8V minimum supply voltage, while the 25LC640A-E/P requires 2.5V minimum. The original AT25640-10PI-2.7 requires 2.7V minimum. For applications operating at 2.5V to 2.7V, the 25AA640A-I/P is the appropriate choice. Both parts support the full 5.5V maximum.

Q: Which substitute part should be selected for extended temperature applications?

A: The 25LC640A-E/P supports an operating temperature range of -40°C to 125°C, compared to -40°C to 85°C for both the original part and the 25AA640A-I/P. Select the 25LC640A-E/P for applications requiring operation above 85°C.

Q: Are there RoHS compliance differences?

A: Yes. The original AT25640-10PI-2.7 is RoHS non-compliant. Both substitute parts (25AA640A-I/P and 25LC640A-E/P) are ROHS3 compliant, meeting current environmental and regulatory requirements.

Q: Is the 8-DIP package footprint identical across all three parts?

A: Yes. All three parts use the same 8-DIP (0.300", 7.62mm) through-hole package format, ensuring direct pin-compatible substitution without PCB layout modifications.