AT27C1024-45JC EPROM Equivalent & Substitute Parts

Part Overview

The AT27C1024-45JC is a 1Mbit parallel EPROM (Erasable Programmable Read-Only Memory) manufactured by Microchip Technology in a 44-PLCC surface mount package. This OTP (One-Time Programmable) memory device operates at 45 ns access time and is designed for legacy embedded systems requiring non-volatile parallel memory storage.

The AT27C1024-45JC carries an Obsolete product status, making substitute parts necessary for ongoing system maintenance, repairs, and component sourcing. The device is RoHS non-compliant and not verified for programming through DiGi-Electronics channels, which may impact procurement and manufacturing workflows.

Substiute Parts

AT27C1024-45JC

Microchip TechnologyIn Stock: 1372AT27C1024-45JC Datasheet

Current PartRFQ

AT27C1024-45JU

Microchip TechnologyIn Stock: 1851AT27C1024-45JU Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AT27C1024-45JC is determined by the following critical parameters:

• Memory Capacity & Organization: 1Mbit capacity with 64K x 16 organization must be maintained for address and data bus compatibility
• Memory Interface Type: Parallel interface is required for direct pin-to-pin compatibility
• Access Time: 45 ns access time establishes the maximum speed requirement
• Package & Pinout: 44-PLCC surface mount package with identical physical dimensions (16.6x16.6) ensures PCB compatibility
• Voltage Supply Range: 4.5V ~ 5.5V operating voltage must be supported
• Manufacturer Compatibility: Microchip Technology AT27C1024 base product family maintains electrical and functional equivalence

The AT27C1024-45JU qualifies as a direct substitute based on identical electrical specifications, matching package configuration, and equivalent memory architecture within the same product family.

Parameter Comparison

Engineering Selection Recommendations

The AT27C1024-45JU is the qualified substitute for the obsolete AT27C1024-45JC based on the following factors:

Electrical Equivalence: Both parts maintain identical memory capacity (1Mbit), organization (64K x 16), parallel interface, access time (45 ns), and supply voltage range (4.5V ~ 5.5V). Pin-to-pin compatibility is assured within the 44-PLCC package.

Product Status: The AT27C1024-45JU carries Active product status, ensuring ongoing availability and manufacturing support from Microchip Technology, whereas the main part is Obsolete.

Compliance & Certification: The substitute part is ROHS3 compliant and verified for programming through DiGi-Electronics channels, providing improved compliance posture and manufacturing process compatibility compared to the non-compliant main part.

Operating Temperature Consideration: The AT27C1024-45JU supports an extended operating temperature range (-40°C ~ 85°C) compared to the main part (0°C ~ 70°C). This expanded range provides additional thermal margin for applications operating at temperature extremes.

Frequently Asked Questions (FAQ)

Q: Can the AT27C1024-45JU directly replace the AT27C1024-45JC on existing PCBs?

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

Q: What is the difference between the -45JC and -45JU package designations?

A: The suffix indicates packaging format. The -45JC uses standard packaging, while the -45JU is supplied in Tube packaging. The electrical specifications and pinout remain identical.

Q: Are there any voltage or timing differences between these parts?

A: No. Both parts operate at 4.5V ~ 5.5V supply voltage and maintain 45 ns access time. They are electrically equivalent for all functional parameters.

Q: Why is the operating temperature range different?

A: The AT27C1024-45JU supports -40°C ~ 85°C, while the main part supports 0°C ~ 70°C. The substitute provides extended thermal operating range. Applications within the original 0°C ~ 70°C window will function identically in both parts.

Q: What is the significance of RoHS3 compliance on the substitute part?

A: RoHS3 compliance indicates the substitute part meets current environmental and hazardous substance restrictions. The main part is RoHS non-compliant. For new designs or manufacturing processes requiring RoHS compliance, the AT27C1024-45JU is the appropriate selection.

Q: Is the AT27C1024-45JU verified for programming?

A: Yes. The AT27C1024-45JU is verified for programming through DiGi-Electronics channels, whereas the main part is not verified. This ensures compatibility with standard programming workflows and equipment.