AT27C4096-70PC Equivalent & Substitute Parts

Part Overview

The AT27C4096-70PC is a 4Mbit parallel EPROM (Erasable Programmable Read-Only Memory) manufactured by Microchip Technology in a 40-pin DIP package. This part is classified as obsolete, making substitute components necessary for new designs, repairs, or production continuity. The AT27C4096 series provides non-volatile memory storage with parallel interface architecture suitable for legacy embedded systems and industrial applications requiring OTP (One-Time Programmable) memory solutions.

Substiute Parts

AT27C4096-70PC

Microchip TechnologyIn Stock: 916AT27C4096-70PC Datasheet

Current PartRFQ

AT27C4096-90PU

Microchip TechnologyIn Stock: 1800AT27C4096-90PU Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the AT27C4096-70PC is determined by the following critical parameters that must remain constant or compatible:

• Memory Capacity & Organization: 4Mbit capacity with 256K x 16 organization is mandatory for functional equivalence
• Memory Technology: EPROM OTP technology must be maintained
• Parallel Interface: The parallel memory interface architecture cannot be changed
• Package & Pinout: 40-DIP package with 0.600" (15.24mm) body ensures mechanical and electrical compatibility
• Supply Voltage: 4.5V ~ 5.5V operating range must be supported
• Access Time: Substitute parts may have equal or faster access times (lower or equal ns values)

The AT27C4096-90PU qualifies as a direct substitute based on these parameters. While it features a slower access time (90 ns vs. 70 ns), this represents a backward-compatible specification change that does not prevent functional substitution in most applications.

Parameter Comparison

Engineering Selection Recommendations

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

• Product Status: The substitute part maintains active status with Microchip Technology, ensuring continued availability and support compared to the obsolete main part
• Compliance: The AT27C4096-90PU achieves ROHS3 compliance, whereas the original part is non-compliant, providing environmental and regulatory advantages for new designs
• Electrical Compatibility: Both parts operate within identical supply voltage ranges (4.5V ~ 5.5V) and maintain the same memory capacity, organization, and parallel interface architecture
• Thermal Range: The substitute part supports an extended operating temperature range (-40°C ~ 85°C vs. 0°C ~ 70°C), providing greater flexibility for diverse application environments
• Access Time Specification: The 90 ns access time of the substitute represents a slower specification than the original 70 ns part. This difference is acceptable in applications where timing margins permit the additional latency

Frequently Asked Questions (FAQ)

Q: Can the AT27C4096-90PU directly replace the AT27C4096-70PC in existing designs?

A: Yes, the AT27C4096-90PU is a direct pin-compatible substitute. Both parts use identical 40-DIP packaging and pinout. The primary difference is access time (90 ns vs. 70 ns). Substitution is valid provided the system timing design accommodates the slower access time specification.

Q: What is the significance of the access time difference between these parts?

A: Access time defines the maximum delay from address setup to valid data output. The AT27C4096-90PU has a 20 ns longer access time than the AT27C4096-70PC. This affects memory read cycle timing. Verify that your system's memory controller and timing constraints can tolerate 90 ns access time before substitution.

Q: Why is the AT27C4096-90PU marked as Active while the AT27C4096-70PC is Obsolete?

A: The AT27C4096-70PC has reached end-of-life status with Microchip Technology and is no longer manufactured. The AT27C4096-90PU remains in active production, ensuring supply availability and ongoing manufacturer support for new applications and repairs.

Q: Are there any compliance differences between these parts?

A: Yes. The AT27C4096-90PU is ROHS3 compliant, while the AT27C4096-70PC is non-compliant. For applications subject to RoHS regulations or environmental standards, the substitute part provides regulatory compliance advantages.

Q: Does the extended temperature range of the AT27C4096-90PU affect substitution decisions?

A: The AT27C4096-90PU supports -40°C ~ 85°C operation compared to 0°C ~ 70°C for the original part. This extended range does not prevent substitution; it provides additional operational flexibility for applications requiring wider temperature tolerance.

Q: What packaging options are available for these parts?

A: Both the AT27C4096-70PC and AT27C4096-90PU are supplied in 40-DIP (0.600", 15.24mm) through-hole packages. The AT27C4096-90PU is available in Tube packaging, while the original part packaging specification is not detailed. Both maintain identical mechanical dimensions and pinout.