AT28C64B-15TU-T Equivalent & Substitute Parts

Part Overview

The AT28C64B-15TU-T is a 64Kbit parallel EEPROM memory IC manufactured by Microchip Technology, packaged in 28-TSSOP with 150 ns access time and 10ms write cycle time. This device is classified as obsolete, making substitute parts necessary for new designs and ongoing production requirements. The part operates across the industrial temperature range of -40°C to 85°C with supply voltage tolerance of 4.5V to 5.5V.

Substiute Parts

AT28C64B-15TU-T

Microchip TechnologyIn Stock: 876AT28C64B-15TU-T Datasheet

Current PartRFQ

AT28C64B-15SU-T

Microchip TechnologyIn Stock: 2872AT28C64B-15SU-T Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AT28C64B-15TU-T is determined by electrical and mechanical compatibility across the following critical parameters:

Electrical Compatibility Requirements:

• Memory capacity: 64Kbit (8K x 8 organization)
• Memory interface: Parallel
• Access time: 150 ns
• Write cycle time: 10ms
• Supply voltage: 4.5V ~ 5.5V
• Operating temperature range: -40°C ~ 85°C

Mechanical Compatibility Requirements:

• Mounting type: Surface Mount
• Package type: 28-pin configuration (TSSOP or SOIC variants)
• RoHS compliance: ROHS3 Compliant
• MSL rating: 3 (168 Hours)

The AT28C64B-15SU-T qualifies as a direct substitute based on identical electrical specifications and RoHS compliance, with the primary difference being package form factor (28-SOIC versus 28-TSSOP).

Parameter Comparison

Engineering Selection Recommendations

The AT28C64B-15SU-T is the qualified substitute for the AT28C64B-15TU-T based on the following factors:

Product Status: The main part is classified as obsolete, while the substitute maintains active product status with current manufacturing availability (2791 pcs in stock versus 789 pcs for the obsolete part).

Electrical Equivalence: All critical electrical parameters are identical, including memory capacity, access time, write cycle time, supply voltage range, and operating temperature specifications.

Compliance Alignment: Both parts maintain ROHS3 compliance and identical MSL ratings, ensuring equivalent environmental and regulatory suitability.

Package Consideration: The primary difference is package form factor. The substitute uses 28-SOIC (0.295" width) versus the main part's 28-TSSOP (0.465" width). PCB layout modifications are required to accommodate the different package dimensions and pin pitch.

Frequently Asked Questions (FAQ)

Q: Can the AT28C64B-15SU-T directly replace the AT28C64B-15TU-T without design changes?

A: Electrical substitution is direct. However, the package form factor differs (28-SOIC versus 28-TSSOP), requiring PCB footprint modification. Pin assignments remain identical across both packages.

Q: What are the key differences between 28-TSSOP and 28-SOIC packages?

A: The 28-SOIC package is narrower (0.295" versus 0.465" width) and uses different lead geometry. Both are surface-mount packages with 28 pins, but PCB layout and assembly tooling must be adjusted accordingly.

Q: Are there any electrical performance differences between these parts?

A: No. Access time (150 ns), write cycle time (10ms), supply voltage range (4.5V ~ 5.5V), and operating temperature range (-40°C ~ 85°C) are identical.

Q: Why is the main part listed as obsolete?

A: The AT28C64B-15TU-T is classified as obsolete by the manufacturer. The AT28C64B-15SU-T maintains active production status and is the recommended path for new designs and production continuity.

Q: Do both parts meet the same compliance standards?

A: Yes. Both parts are ROHS3 compliant with identical MSL ratings of 3 (168 Hours), ensuring equivalent environmental and regulatory compliance.

Q: What is the inventory status for each part?

A: The AT28C64B-15TU-T has 789 pcs available. The AT28C64B-15SU-T has 2791 pcs available, providing greater supply security for production requirements.