AT28C64-12PC Equivalent & Substitute Parts

Part Overview

The AT28C64-12PC is a 64Kbit parallel EEPROM memory IC manufactured by Microchip Technology, housed in a 28-DIP package with 120 ns access time. This part is classified as obsolete, which necessitates identification of functionally compatible alternatives for ongoing system support and new designs. The AT28C64-12PC remains in stock inventory but is no longer in active production, making substitute parts critical for long-term component availability and supply chain continuity.

Substiute Parts

AT28C64-12PC

Microchip TechnologyIn Stock: 8064AT28C64-12PC Datasheet

Current PartRFQ

AT28C64B-15PU

Microchip TechnologyIn Stock: 3411AT28C64B-15PU Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AT28C64-12PC is determined by the following critical parameters:

• Memory Capacity & Organization: 64Kbit capacity with 8K x 8 organization is mandatory for pin-compatible replacement
• Package & Pinout: 28-DIP package ensures mechanical and electrical compatibility with existing PCB layouts
• Voltage Supply Range: 4.5V ~ 5.5V compatibility maintains operational consistency with system power supplies
• Interface Type: Parallel interface is required for direct functional replacement
• Access Time: Substitute parts with equal or faster access time (≤120 ns) ensure timing compatibility

The AT28C64B-15PU meets all substitution criteria while offering improved product status and compliance certifications.

Parameter Comparison

Engineering Selection Recommendations

The AT28C64B-15PU is the qualified substitute for the AT28C64-12PC based on the following factors:

• Product Status: The substitute part is in active production status, ensuring long-term availability and supply chain reliability compared to the obsolete main part
• Regulatory Compliance: The AT28C64B-15PU is ROHS3 compliant, meeting current environmental and regulatory requirements, whereas the main part is non-compliant
• Functional Compatibility: Both parts share identical memory capacity, organization, package type, and voltage supply specifications, enabling direct replacement in existing designs
• Temperature Range: The substitute part supports an extended operating temperature range (-40°C ~ 85°C), providing greater operational flexibility for diverse environmental conditions
• Electrical Characteristics: Access time and write cycle time differences are within acceptable margins for most parallel EEPROM applications; timing-critical designs must validate performance requirements

Frequently Asked Questions (FAQ)

Q: Can the AT28C64B-15PU be used as a direct replacement for the AT28C64-12PC?

A: Yes. Both parts share identical memory capacity (64Kbit), organization (8K x 8), package type (28-DIP), and voltage supply range (4.5V ~ 5.5V). The 28-pin DIP package ensures mechanical and electrical compatibility with existing PCB layouts and socket configurations.

Q: What are the differences in access time between these parts?

A: The AT28C64-12PC has 120 ns access time, while the AT28C64B-15PU has 150 ns access time. The substitute part is 30 ns slower. For applications with strict timing requirements, system-level timing analysis is necessary to confirm compatibility.

Q: Does the write cycle time difference affect compatibility?

A: The AT28C64-12PC has 1 ms write cycle time; the AT28C64B-15PU has 10 ms write cycle time. This difference affects write operation duration but does not prevent functional substitution. Applications performing frequent write operations should account for the extended write cycle time in system timing calculations.

Q: Are there packaging differences between these parts?

A: The AT28C64-12PC is supplied in standard packaging; the AT28C64B-15PU is supplied in Tube packaging. Both use identical 28-DIP (0.600", 15.24mm) package cases suitable for through-hole mounting on PCBs.

Q: What is the significance of the RoHS compliance difference?

A: The AT28C64-12PC is RoHS non-compliant; the AT28C64B-15PU is ROHS3 compliant. For applications subject to environmental regulations or customer requirements mandating RoHS compliance, the substitute part is the appropriate selection.

Q: Can the AT28C64B-15PU operate in the same temperature range as the AT28C64-12PC?

A: The AT28C64-12PC operates from 0°C to 70°C; the AT28C64B-15PU operates from -40°C to 85°C. The substitute part covers the main part's temperature range and extends operation to lower and higher temperatures, providing greater environmental flexibility.