AT27C4096-70PI Equivalent & Substitute Parts

Part Overview

The AT27C4096-70PI is a 4Mbit parallel EPROM (Erasable Programmable Read-Only Memory) manufactured by Microchip Technology in a 40-pin DIP package with 70 ns access time. This part is classified as obsolete, which necessitates identification of functionally equivalent alternatives for ongoing system support and new designs. The AT27C4096 series remains in use in legacy industrial and embedded systems where parallel EPROM technology is required.

Substiute Parts

AT27C4096-70PI

Microchip TechnologyIn Stock: 859AT27C4096-70PI Datasheet

Current PartRFQ

AT27C4096-90PU

Microchip TechnologyIn Stock: 1800AT27C4096-90PU Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AT27C4096-70PI is determined by the following critical parameters that must remain constant:

• Memory capacity (4Mbit)
• Memory organization (256K x 16)
• Parallel interface architecture
• Package form factor (40-DIP)
• Supply voltage range (4.5V ~ 5.5V)
• Operating temperature range (-40°C ~ 85°C)
• Through-hole mounting compatibility

The AT27C4096-90PU qualifies as a direct substitute based on identical electrical and mechanical specifications. The primary difference is access time (90 ns versus 70 ns), which represents a relaxed timing specification suitable for applications where the slower access time does not violate system timing requirements.

Parameter Comparison

Engineering Selection Recommendations

The AT27C4096-90PU is the qualified substitute for the AT27C4096-70PI based on the following factors:

• Identical memory capacity, organization, and parallel interface specifications
• Identical package footprint and through-hole mounting compatibility
• Identical supply voltage and operating temperature ranges
• Active product status with verified availability
• ROHS3 compliance, addressing regulatory requirements for new designs and production runs
• Access time specification (90 ns) is relaxed relative to the original part; system timing analysis must confirm that the slower access time does not violate critical path requirements

The AT27C4096-90PU is suitable for direct replacement in applications where the 90 ns access time meets system timing constraints.

Frequently Asked Questions (FAQ)

Q: Can the AT27C4096-90PU be used as a direct pin-for-pin replacement for the AT27C4096-70PI?

A: Yes. Both parts use the 40-DIP package with identical pinout, supply voltage, and operating temperature specifications. Pin compatibility is confirmed.

Q: What is the impact of the 20 ns difference in access time?

A: The AT27C4096-90PU has a slower access time (90 ns versus 70 ns). This affects the maximum read cycle speed. System timing analysis is required to confirm that the slower access time does not violate setup and hold time requirements for the memory interface.

Q: Is the AT27C4096-90PU available in the same packaging as the AT27C4096-70PI?

A: Both parts are supplied in 40-DIP through-hole packages with identical physical dimensions (0.600", 15.24mm). The AT27C4096-90PU is supplied in tube packaging.

Q: What is the difference in RoHS compliance between these parts?

A: The AT27C4096-70PI is RoHS non-compliant. The AT27C4096-90PU is ROHS3 compliant, meeting current environmental and regulatory standards for new production and design implementations.

Q: Are there any differences in memory organization or capacity?

A: No. Both parts are 4Mbit EPROMs with 256K x 16 organization and parallel interface architecture.

Q: Why is the AT27C4096-70PI classified as obsolete?

A: The AT27C4096-70PI is an older product variant. The AT27C4096-90PU represents the active product line from Microchip Technology with improved compliance status and ongoing availability.