AT27C256R-15JC Equivalent & Substitute Parts

Part Overview

The AT27C256R-15JC is a 256Kbit EPROM (Erasable Programmable Read-Only Memory) manufactured by Microchip Technology in a 32-PLCC surface mount package. This part operates with a 150 ns access time and is designed for parallel memory interface applications requiring non-volatile storage. The AT27C256R-15JC is classified as obsolete, making equivalent substitute parts necessary for ongoing system support and new design implementations where this memory capacity and interface type are required.

Substiute Parts

AT27C256R-15JC

Microchip TechnologyIn Stock: 2039AT27C256R-15JC Datasheet

Current PartRFQ

AT27C256R-45JU

Microchip TechnologyIn Stock: 2237AT27C256R-45JU Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the AT27C256R-15JC is determined by strict equivalence across the following parameters:

• Memory capacity: 256Kbit
• Memory organization: 32K x 8 configuration
• Memory format: EPROM technology
• Interface type: Parallel
• Package: 32-PLCC surface mount
• Supply voltage: 4.5V ~ 5.5V compatibility
• Pin count and physical dimensions: 32-PLCC (13.97x11.43)

The AT27C256R-45JU qualifies as a direct substitute based on matching all core electrical and mechanical parameters. Variations in access time and operating temperature range do not prevent substitution when system timing requirements permit the faster access time specification.

Parameter Comparison

Engineering Selection Recommendations

The AT27C256R-45JU is an active product with ROHS3 compliance, addressing the obsolescence status of the AT27C256R-15JC. The substitute part provides improved access time (45 ns versus 150 ns) and an extended operating temperature range (-40°C ~ 85°C versus 0°C ~ 70°C), making it suitable for applications requiring broader environmental specifications. Both parts maintain identical supply voltage requirements and package dimensions, ensuring direct physical and electrical compatibility in 32-PLCC socket applications.

Frequently Asked Questions (FAQ)

Q: Can the AT27C256R-45JU replace the AT27C256R-15JC in existing designs?

A: Yes. Both parts share identical memory capacity (256Kbit), organization (32K x 8), interface type (Parallel), supply voltage (4.5V ~ 5.5V), and 32-PLCC package dimensions. The faster access time of the substitute part (45 ns) is backward compatible with systems designed for 150 ns operation.

Q: What is the primary difference between these two parts?

A: The AT27C256R-45JU offers faster access time (45 ns) and an extended operating temperature range (-40°C ~ 85°C) compared to the AT27C256R-15JC (150 ns, 0°C ~ 70°C). The substitute is also an active product with ROHS3 compliance, whereas the main part is obsolete and RoHS non-compliant.

Q: Are the physical packages identical?

A: Yes. Both parts use the 32-PLCC (13.97x11.43) surface mount package with identical pin configurations and dimensions, allowing direct socket substitution.

Q: Does the faster access time of the substitute create any compatibility issues?

A: No. Faster access time is a performance enhancement that does not create compatibility issues in systems designed for the original 150 ns specification. System timing margins are maintained or improved.

Q: What compliance advantages does the substitute offer?

A: The AT27C256R-45JU is ROHS3 compliant and carries active product status, whereas the AT27C256R-15JC is obsolete and RoHS non-compliant. This makes the substitute suitable for new designs and applications with environmental compliance requirements.