AT27C1024-12VC Equivalent & Substitute Parts

Part Overview

The AT27C1024-12VC is a 1Mbit parallel EPROM (Erasable Programmable Read-Only Memory) manufactured by Microchip Technology in a 40-VSOP package with 120 ns access time. This component is classified as obsolete, making equivalent or substitute parts necessary for new designs, maintenance, or production continuity. The part operates within a 4.5V to 5.5V supply voltage range and supports industrial temperature ranges from 0°C to 70°C.

Substiute Parts

AT27C1024-12VC

Microchip TechnologyIn Stock: 1180AT27C1024-12VC Datasheet

Current PartRFQ

AT27C010-45JU

Microchip TechnologyIn Stock: 1220AT27C010-45JU Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AT27C1024-12VC is determined by the following critical parameters:

• Memory Capacity: 1Mbit total storage
• Memory Organization: 64K x 16 bit configuration
• Interface Type: Parallel access protocol
• Supply Voltage: 4.5V to 5.5V compatibility
• Access Time: 120 ns or faster
• Package Compatibility: Surface mount form factor

The AT27C010-45JU qualifies as a substitute based on matching memory capacity (1Mbit), parallel interface, and compatible supply voltage range. However, differences exist in memory organization (128K x 8 vs. 64K x 16), package type (32-PLCC vs. 40-VSOP), access time (45 ns vs. 120 ns), and operating temperature range. These differences require circuit-level evaluation for functional compatibility.

Parameter Comparison

Engineering Selection Recommendations

The AT27C010-45JU is an active product with ROHS3 compliance and extended operating temperature range (-40°C to 85°C), providing advantages over the obsolete AT27C1024-12VC. The substitute offers faster access time (45 ns vs. 120 ns), which is compatible with timing-critical applications.

Key considerations for selection:

• Product Availability: AT27C010-45JU is active; AT27C1024-12VC is obsolete
• Compliance: AT27C010-45JU meets ROHS3 requirements; AT27C1024-12VC does not
• Temperature Range: AT27C010-45JU supports extended industrial range (-40°C to 85°C)
• Package Footprint: Different package types (40-VSOP vs. 32-PLCC) require PCB redesign
• Memory Organization: Different bit-width organization (16-bit vs. 8-bit) affects address/data line mapping

Frequently Asked Questions (FAQ)

Q: Can AT27C010-45JU directly replace AT27C1024-12VC without PCB modification?

A: No. The parts use different package types (40-VSOP vs. 32-PLCC) and memory organization (64K x 16 vs. 128K x 8), requiring PCB redesign and firmware/address mapping adjustments.

Q: Are the supply voltage requirements identical?

A: Yes. Both parts operate within 4.5V to 5.5V supply voltage range, ensuring power supply compatibility.

Q: What is the impact of the different access times (120 ns vs. 45 ns)?

A: The AT27C010-45JU has faster access time, which is backward-compatible with designs expecting 120 ns or slower. No timing violations occur when substituting with the faster part.

Q: Does the AT27C010-45JU meet modern compliance standards?

A: Yes. The AT27C010-45JU is ROHS3 compliant with MSL rating of 2 (1 Year), compared to the non-compliant AT27C1024-12VC with MSL rating of 3 (168 Hours).

Q: What is the significance of different memory organization?

A: AT27C1024-12VC uses 64K x 16 (16-bit words), while AT27C010-45JU uses 128K x 8 (8-bit words). This affects address line count and data bus width, requiring circuit redesign for compatibility.

Q: Is the extended temperature range of AT27C010-45JU beneficial?

A: The AT27C010-45JU supports -40°C to 85°C, exceeding the AT27C1024-12VC range of 0°C to 70°C. This provides broader environmental operating capability for industrial applications.