93LC66AT-E/SN EEPROM Memory IC Equivalent & Substitute Parts

Part Overview

The 93LC66AT-E/SN is a 4Kbit non-volatile EEPROM memory integrated circuit manufactured by Microchip Technology. This device operates using the Microwire serial interface protocol and is housed in an 8-SOIC surface mount package. The part is currently in active production status with verified programmability through DiGi-Electronics. Substitute parts are identified when equivalent electrical specifications, memory organization, interface protocol, and package dimensions are maintained across alternative part numbers or packaging configurations from the same manufacturer.

Substiute Parts

93LC66AT-E/SN

Microchip TechnologyIn Stock: 98393LC66AT-E/SN Datasheet

Current PartRFQ

93LC66A-E/SN

Microchip TechnologyIn Stock: 325893LC66A-E/SN Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The 93LC66A-E/SN qualifies as a direct substitute for the 93LC66AT-E/SN based on the following critical parameters:

• Memory Capacity & Organization: Both devices provide 4Kbit capacity with 512 x 8 organization
• Interface Protocol: Both implement Microwire serial interface at 2 MHz clock frequency
• Electrical Specifications: Identical supply voltage range (2.5V to 5.5V) and write cycle time (6ms)
• Operating Temperature: Both rated for -40°C to 125°C operation
• Package Footprint: Both use 8-SOIC package with identical 0.154" (3.90mm) width
• Compliance & Certifications: Both are ROHS3 compliant with MSL 1 rating and REACH unaffected status
• Manufacturer: Both manufactured by Microchip Technology with active product status

The primary difference between these parts is the packaging configuration: the main part (93LC66AT-E/SN) is supplied in Tape & Reel format, while the substitute (93LC66A-E/SN) is supplied in Tube packaging. This distinction affects logistics and handling but does not alter functional or electrical compatibility.

Parameter Comparison

Engineering Selection Recommendations

Both the 93LC66AT-E/SN and 93LC66A-E/SN are suitable for applications requiring 4Kbit Microwire EEPROM functionality. Selection between these parts should be based on packaging and supply chain requirements:

• 93LC66AT-E/SN (Tape & Reel): Preferred for high-volume automated assembly operations where reel-based component feeding is standard
• 93LC66A-E/SN (Tube): Suitable for lower-volume production, manual assembly, or applications where tube packaging aligns with existing supply chain infrastructure

Both parts maintain identical electrical performance, thermal characteristics, and regulatory compliance. The choice between them does not impact circuit design, PCB layout, or firmware implementation. Both devices are verified as programmable through DiGi-Electronics and carry active product status from Microchip Technology, ensuring long-term availability and support.

Frequently Asked Questions (FAQ)

Q: Can 93LC66A-E/SN replace 93LC66AT-E/SN in existing designs?

A: Yes. The electrical specifications, memory capacity, interface protocol, package footprint, and operating parameters are identical. The only difference is the packaging format (Tube vs. Tape & Reel), which does not affect circuit functionality or PCB compatibility.

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

A: Tape & Reel (TR) packaging is optimized for automated pick-and-place assembly with continuous reel feeding. Tube packaging is used for manual handling and lower-volume applications. Both formats contain the same die and provide identical performance.

Q: Are both parts RoHS compliant?

A: Yes. Both 93LC66AT-E/SN and 93LC66A-E/SN are ROHS3 compliant and carry MSL 1 (Unlimited) moisture sensitivity ratings, making them suitable for standard PCB assembly processes without special handling requirements.

Q: What is the Microwire interface, and is it standard across both parts?

A: Microwire is a three-wire serial communication protocol (clock, data in, data out) used for EEPROM programming and reading. Both parts implement identical Microwire protocol at 2 MHz, ensuring full compatibility with existing host controllers and firmware.

Q: Can these parts be used interchangeably in production?

A: Yes, provided your assembly process can accommodate the packaging format. If your production line uses automated reel feeding, use 93LC66AT-E/SN. If manual component placement or tube-based supply is preferred, use 93LC66A-E/SN. No circuit redesign or firmware modification is required.

Q: What is the write cycle time, and does it differ between these parts?

A: Both parts have a 6ms write cycle time for word and page operations. This specification is identical and does not vary between the two part numbers.