AT93C66-10PI-2.5 Equivalent & Substitute Parts

Part Overview

The AT93C66-10PI-2.5 is a 4Kbit EEPROM memory IC manufactured by Microchip Technology, featuring a 3-Wire Serial interface operating at 2 MHz. This device is designed for non-volatile data storage applications requiring through-hole mounting in 8-DIP packaging. The part is currently classified as obsolete, making identification of compatible substitute components essential for ongoing system support and new design implementations.

Substiute Parts

AT93C66-10PI-2.5

Microchip TechnologyIn Stock: 936AT93C66-10PI-2.5 Datasheet

Current PartRFQ

93AA66C-I/P

Microchip TechnologyIn Stock: 182693AA66C-I/P Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AT93C66-10PI-2.5 is determined by the following critical parameters:

Memory Capacity & Organization: The substitute must provide 4Kbit capacity with 512 x 8 or 256 x 16 organization to maintain functional equivalence in data storage applications.

Package & Mounting: The 8-DIP through-hole package is mandatory for PCB compatibility. Pin count and physical dimensions must remain consistent.

Interface Protocol: The original device uses 3-Wire Serial interface. Substitute parts must support compatible serial communication protocols (3-Wire Serial or Microwire) to ensure signal-level compatibility with existing circuit designs.

Electrical Specifications: Supply voltage range and operating temperature must encompass or match the original specifications to guarantee operation within the same system environment.

Product Status & Compliance: Active product status and modern compliance certifications (RoHS3, REACH) are preferred for long-term availability and regulatory alignment, though not absolute requirements for functional substitution.

Parameter Comparison

Engineering Selection Recommendations

The 93AA66C-I/P serves as a direct functional substitute for the AT93C66-10PI-2.5 based on matching memory capacity, organization, and physical packaging. Both devices are manufactured by Microchip Technology and share identical 8-DIP through-hole form factors.

The 93AA66C-I/P offers several advantages for new implementations and system upgrades:

Product Availability: Active product status ensures long-term supply chain availability compared to the obsolete AT93C66-10PI-2.5.

Regulatory Compliance: ROHS3 compliance and REACH unaffected status align with current environmental and regulatory requirements for commercial and industrial applications.

Enhanced Performance: The substitute provides faster write cycle time (6ms vs. 10ms) and higher clock frequency (3 MHz vs. 2 MHz), delivering improved performance characteristics.

Expanded Voltage Range: The 1.8V lower minimum supply voltage extends operational flexibility in low-power applications.

Interface Compatibility: Microwire protocol is a superset of 3-Wire Serial functionality, ensuring protocol-level compatibility with existing circuit implementations.

Frequently Asked Questions (FAQ)

Q: Can the 93AA66C-I/P directly replace the AT93C66-10PI-2.5 without circuit modifications?

A: Yes. Both devices share identical memory capacity (4Kbit), organization (512 x 8, 256 x 16), 8-DIP package dimensions, and operating temperature range. The Microwire interface of the substitute is compatible with 3-Wire Serial protocol requirements. No PCB layout changes are required.

Q: What is the difference between 3-Wire Serial and Microwire interfaces?

A: Microwire is an enhanced serial protocol that maintains backward compatibility with 3-Wire Serial communication. The 93AA66C-I/P operates using Microwire protocol while supporting the same pin configuration and signal timing as the original 3-Wire Serial device.

Q: Does the faster write cycle time (6ms vs. 10ms) affect system compatibility?

A: No. The faster write cycle time of the substitute is a performance improvement that does not create compatibility issues. Systems designed for the original 10ms cycle time will operate correctly with the faster 6ms specification.

Q: Is the expanded voltage range (1.8V ~ 5.5V vs. 2.5V ~ 5.5V) significant for my application?

A: The expanded lower voltage limit provides additional flexibility for low-power or battery-operated systems. If your application operates above 2.5V, both devices are functionally equivalent in this parameter.

Q: Why is RoHS compliance important for this substitution?

A: ROHS3 compliance of the 93AA66C-I/P ensures the substitute meets current environmental regulations for hazardous substance restrictions. This is particularly important for products destined for European markets or applications subject to regulatory compliance requirements.

Q: Are there any pin-to-pin differences between these devices?

A: No. Both the AT93C66-10PI-2.5 and 93AA66C-I/P use identical 8-DIP pinouts. Direct socket substitution is possible without rewiring or circuit redesign.

Q: What is the MSL rating and why does it matter?

A: MSL (Moisture Sensitivity Level) 1 rating for the 93AA66C-I/P indicates unlimited shelf life without moisture control requirements. This simplifies inventory management and reduces handling constraints compared to higher MSL ratings.