AT49F001N-55PC Equivalent & Substitute Parts

Part Overview

The AT49F001N-55PC is a 1Mbit parallel FLASH memory IC manufactured by Microchip Technology, housed in a 32-DIP package with 55 ns access time. This device is classified as obsolete and is no longer in active production. Due to its obsolete status and limited availability for new designs, identifying functionally compatible substitute components is essential for system maintenance, legacy product support, and design continuity.

Substiute Parts

AT49F001N-55PC

Microchip TechnologyIn Stock: 846AT49F001N-55PC Datasheet

Current PartRFQ

SST39SF020A-70-4C-PHE

Microchip TechnologyIn Stock: 1837SST39SF020A-70-4C-PHE Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution compatibility for the AT49F001N-55PC is determined by the following critical parameters:

Mandatory Compatibility Criteria:

• Memory Interface: Parallel (pin-compatible architecture required)
• Package Type: 32-DIP form factor (physical and electrical pin compatibility)
• Voltage Supply Range: 4.5V ~ 5.5V (operational voltage compatibility)
• Memory Organization: 128K x 8 minimum (address and data bus alignment)
• Mounting Type: Through Hole (PCB integration method)

Performance Parameters:

• Access Time: 55 ns or faster (timing margin for system operation)
• Write Cycle Time: 50 µs or faster (programming speed compatibility)

The SST39SF020A-70-4C-PHE meets all mandatory compatibility criteria while offering enhanced specifications in memory capacity and compliance status.

Parameter Comparison

Engineering Selection Recommendations

The SST39SF020A-70-4C-PHE is a direct functional substitute for the AT49F001N-55PC based on the following engineering criteria:

Compatibility Factors:

• Identical parallel memory interface and 32-DIP package ensure pin-level compatibility
• Matching voltage supply range (4.5V ~ 5.5V) and operating temperature range (0°C ~ 70°C) provide electrical compatibility
• Access time of 70 ns is within acceptable timing margins for systems designed for 55 ns operation

Advantages of Substitution:

• Active product status ensures long-term availability and supply chain continuity
• ROHS3 compliance meets current environmental and regulatory requirements
• Doubled memory capacity (2Mbit vs. 1Mbit) provides additional functional headroom
• Faster write cycle time (20 µs vs. 50 µs) improves programming performance

Compliance Considerations:

• The substitute part meets modern RoHS3 compliance standards, whereas the original part does not
• Both parts maintain REACH unaffected status and EAR99 export classification

Frequently Asked Questions (FAQ)

Q: Can the SST39SF020A-70-4C-PHE directly replace the AT49F001N-55PC without PCB modifications?

A: Yes. Both devices use identical 32-DIP through-hole packaging with matching pin assignments for parallel FLASH memory operation. No PCB layout changes are required for physical installation.

Q: What is the impact of the 70 ns access time on the SST39SF020A-70-4C-PHE compared to the 55 ns specification of the AT49F001N-55PC?

A: The 15 ns difference in access time is within typical system timing margins for parallel FLASH memory applications. Systems designed for 55 ns operation will function correctly with the 70 ns substitute part. Verify timing requirements in your specific application's memory controller specifications.

Q: Does the increased memory capacity (2Mbit vs. 1Mbit) of the substitute part affect compatibility?

A: No. The substitute part maintains the same 256K x 8 organization structure as the original 128K x 8, with additional address lines for the expanded capacity. Existing firmware and memory maps will function without modification. The additional capacity provides design flexibility for future enhancements.

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

A: No. Both parts operate within identical voltage supply ranges (4.5V ~ 5.5V) and temperature ranges (0°C ~ 70°C), ensuring equivalent electrical performance in the same system environment.

Q: Why is RoHS compliance status different between the two parts?

A: The AT49F001N-55PC is an obsolete part manufactured before RoHS3 requirements became standard. The SST39SF020A-70-4C-PHE is an active product manufactured to current RoHS3 compliance standards. For new designs and regulatory compliance, the substitute part is the appropriate choice.

Q: What packaging format is the SST39SF020A-70-4C-PHE supplied in?

A: The substitute part is supplied in Tube packaging, suitable for automated assembly and manual handling. Verify packaging requirements for your procurement and assembly processes.