AT27C4096-12JC Equivalent & Substitute Parts

Part Overview

The AT27C4096-12JC is a 4Mbit parallel EPROM (Erasable Programmable Read-Only Memory) manufactured by Microchip Technology in a 44-PLCC surface mount package. This device is classified as obsolete, indicating it has been discontinued and is no longer in active production. The part operates with a 120 ns access time and supports a supply voltage range of 4.5V to 5.5V across an operating temperature range of 0°C to 70°C. Due to its obsolete status and limited availability in new production cycles, identifying functionally equivalent substitute parts is essential for system redesign, legacy product support, and procurement continuity.

Substiute Parts

AT27C4096-12JC

Microchip TechnologyIn Stock: 1744AT27C4096-12JC Datasheet

Current PartRFQ

AT27C4096-90JU

Microchip TechnologyIn Stock: 6127AT27C4096-90JU Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AT27C4096-12JC is determined by strict equivalence across the following critical parameters:

• Memory Capacity & Organization: Substitute parts must maintain 4Mbit capacity with 256K x 16 organization to ensure direct functional replacement without firmware or hardware modifications.
• Memory Technology: Both main and substitute parts must be EPROM (OTP) technology with parallel interface architecture.
• Package & Pinout: The 44-PLCC surface mount package with identical physical dimensions (16.6x16.6) is mandatory for PCB compatibility.
• Voltage Supply Range: Supply voltage specifications must encompass or match the 4.5V to 5.5V range.
• Access Time: The substitute part's access time must be equal to or faster than the main part's 120 ns specification to maintain system timing compatibility.

The AT27C4096-90JU qualifies as a direct substitute based on these parameters. It shares identical memory capacity, organization, technology, package configuration, and voltage specifications. The faster 90 ns access time provides improved performance margin while maintaining backward compatibility.

Parameter Comparison

Engineering Selection Recommendations

The AT27C4096-90JU is the qualified substitute for the AT27C4096-12JC based on the following engineering criteria:

Functional Equivalence: Both parts share identical memory capacity (4Mbit), organization (256K x 16), technology (EPROM OTP), and parallel interface architecture. The pinout and package footprint are identical, enabling direct PCB-level replacement without layout modifications.

Performance Improvement: The substitute part provides a faster access time of 90 ns compared to the main part's 120 ns, resulting in improved system timing margins and enhanced performance characteristics.

Product Status & Availability: The AT27C4096-90JU maintains active production status with verified availability (6102 units in stock), whereas the main part is obsolete with limited procurement options. This transition ensures long-term supply chain continuity.

Compliance Enhancement: The substitute part achieves ROHS3 compliance and extends the operating temperature range to -40°C to 85°C, providing broader environmental operating conditions compared to the main part's 0°C to 70°C range.

Frequently Asked Questions (FAQ)

Q: Can the AT27C4096-90JU be used as a direct replacement for the AT27C4096-12JC without PCB modifications?

A: Yes. Both parts share identical pinout, package dimensions (44-PLCC 16.6x16.6), and electrical interface specifications. No PCB layout changes are required for substitution.

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

A: The main differences are access time (90 ns vs. 120 ns), product status (active vs. obsolete), operating temperature range (-40°C to 85°C vs. 0°C to 70°C), and RoHS compliance (ROHS3 vs. non-compliant). The faster access time of the substitute part provides improved performance.

Q: Are there any timing compatibility concerns when substituting the AT27C4096-90JU for the AT27C4096-12JC?

A: No. The substitute part's faster 90 ns access time is equal to or better than the main part's 120 ns specification, ensuring system timing requirements are met or exceeded.

Q: Does the extended operating temperature range of the AT27C4096-90JU affect compatibility?

A: No. The substitute part's operating range of -40°C to 85°C encompasses the main part's 0°C to 70°C range, providing broader environmental compatibility without introducing any functional conflicts.

Q: What is the significance of the RoHS3 compliance difference?

A: The AT27C4096-90JU meets ROHS3 compliance standards, whereas the main part is non-compliant. For applications subject to RoHS regulations or environmental compliance requirements, the substitute part is the appropriate selection.

Q: Is the AT27C4096-90JU available in the same packaging format?

A: Yes. Both parts are supplied in 44-PLCC surface mount packages with identical physical dimensions. The substitute part is available in tube packaging with verified programmability.