AT28C64X-15JC Equivalent & Substitute Parts

Part Overview

The AT28C64X-15JC is a 64Kbit parallel EEPROM memory IC manufactured by Microchip Technology, housed in a 32-PLCC package with 150 ns access time. This device is classified as obsolete, which necessitates identification of functionally equivalent alternatives for ongoing system support and new designs. The part operates within a 4.5V to 5.5V supply range and supports 8K x 8 memory organization with parallel interface architecture.

Substiute Parts

AT28C64X-15JC

Microchip TechnologyIn Stock: 1011AT28C64X-15JC Datasheet

Current PartRFQ

AT28C64B-15JU

Microchip TechnologyIn Stock: 16725AT28C64B-15JU Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the AT28C64X-15JC is determined by the following critical parameters:

• Memory capacity and organization (64Kbit, 8K x 8)
• Parallel interface architecture
• Package compatibility (32-PLCC J-Lead form factor)
• Supply voltage range (4.5V ~ 5.5V)
• Access time specification (150 ns or faster)

The AT28C64B-15JU qualifies as a direct substitute based on matching memory size, organization, interface type, package configuration, and electrical specifications. The primary distinction is product status: AT28C64B-15JU is active production, whereas AT28C64X-15JC is obsolete.

Parameter Comparison

Engineering Selection Recommendations

The AT28C64B-15JU is the qualified substitute for AT28C64X-15JC applications. Selection is supported by:

• Identical memory capacity, organization, and parallel interface
• Matching package footprint (32-PLCC J-Lead)
• Equivalent supply voltage specifications
• Identical access time performance (150 ns)
• Active production status ensuring availability
• ROHS3 compliance for regulatory alignment

The AT28C64B-15JU operates across an extended temperature range (-40°C to 85°C) compared to the original part (0°C to 70°C), providing broader environmental compatibility. Write cycle time differs (10ms versus 1ms), which must be evaluated against application timing requirements.

Frequently Asked Questions (FAQ)

Q: Can AT28C64B-15JU directly replace AT28C64X-15JC in existing designs?

A: Yes. Both devices share identical memory capacity (64Kbit), organization (8K x 8), parallel interface, package configuration (32-PLCC), and access time (150 ns). Pin-to-pin compatibility is maintained.

Q: What is the significance of the write cycle time difference (1ms vs. 10ms)?

A: Write cycle time defines the duration required to complete a single write operation. The AT28C64B-15JU requires 10ms per write cycle compared to 1ms for AT28C64X-15JC. Applications with sequential write operations must account for this extended timing.

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

A: No. The AT28C64B-15JU temperature range (-40°C to 85°C) encompasses the original part's range (0°C to 70°C). This provides equal or superior performance across all original operating conditions.

Q: Is RoHS compliance a functional requirement for substitution?

A: RoHS compliance is a regulatory and procurement consideration, not a functional parameter. AT28C64B-15JU ROHS3 compliance may be required for new designs or specific supply chain requirements.

Q: Are there alternative substitutes beyond AT28C64B-15JU?

A: The AT28C64B-15JU is the primary direct substitute. Secondary alternatives (AT28HC64B-70JU, AT28HC64B-90JU, AT28HC64B-12JU) are listed as substitutes for AT28C64B-15JU and may require additional evaluation for specific application requirements.