AT28C64-15SC Equivalent & Substitute Parts

Part Overview

The AT28C64-15SC is a 64Kbit parallel EEPROM memory IC manufactured by Microchip Technology in a 28-SOIC package. This device is classified as obsolete, which necessitates identification of functionally equivalent alternatives for ongoing system support and new designs. The part operates with a 150 ns access time and supports standard 4.5V to 5.5V supply voltage operation across a 0°C to 70°C temperature range.

Substiute Parts

AT28C64-15SC

Microchip TechnologyIn Stock: 2275AT28C64-15SC Datasheet

Current PartRFQ

AT28C64B-15SU

Microchip TechnologyIn Stock: 17897AT28C64B-15SU Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the AT28C64-15SC is determined by the following critical parameters:

• Memory capacity and organization (64Kbit, 8K x 8 configuration)
• Parallel interface architecture
• Access time specification (150 ns)
• Supply voltage compatibility (4.5V ~ 5.5V)
• Package form factor (28-SOIC)
• Pin-compatible pinout

The AT28C64B-15SU meets all substitution criteria. Both devices share identical memory specifications, access time, voltage requirements, and physical packaging. The substitute part maintains full electrical and mechanical compatibility with the original design.

Parameter Comparison

Engineering Selection Recommendations

The AT28C64B-15SU is the direct substitute for the AT28C64-15SC. Selection of the substitute part is justified by:

• Active product status versus obsolete classification of the original part
• Full electrical compatibility across all critical memory parameters
• Identical access time and voltage specifications
• Pin-compatible 28-SOIC package
• ROHS3 compliance versus non-compliant status of the original
• Extended operating temperature range (-40°C to 85°C) providing broader application support
• Verified programmability status

The extended write cycle time (10 ms versus 1 ms) must be evaluated against specific application timing requirements. For applications where the original 1 ms write cycle is critical, this parameter difference requires design review.

Frequently Asked Questions (FAQ)

Q: Can AT28C64B-15SU be used as a direct replacement for AT28C64-15SC?

A: Yes. Both devices are pin-compatible 28-SOIC packages with identical memory capacity, organization, access time, and supply voltage specifications. The substitute part is electrically and mechanically compatible for direct board-level substitution.

Q: What is the difference in write cycle time between these parts?

A: The AT28C64-15SC specifies 1 ms write cycle time, while the AT28C64B-15SU specifies 10 ms. Applications requiring rapid sequential write operations must account for this timing difference during system design validation.

Q: Does the extended temperature range of AT28C64B-15SU affect compatibility?

A: No. The substitute part's extended operating range (-40°C to 85°C) is a superset of the original part's range (0°C to 70°C). This provides enhanced flexibility for applications across wider environmental conditions without reducing compatibility.

Q: Are there packaging differences between these parts?

A: Both parts use 28-SOIC surface mount packaging with identical physical dimensions (0.295", 7.50mm width). No PCB layout modifications are required for substitution.

Q: What is the significance of RoHS compliance status?

A: The AT28C64B-15SU is ROHS3 compliant, while the original AT28C64-15SC is non-compliant. For applications subject to RoHS regulatory requirements, the substitute part provides compliant component selection.