11AA040T-I/MS Equivalent & Substitute Parts

Part Overview

The 11AA040T-I/MS is a 4Kbit EEPROM memory IC manufactured by Microchip Technology, featuring single-wire interface operation at 100 kHz. This non-volatile memory device is designed for applications requiring low-pin-count serial communication in 8-MSOP surface mount packaging. The part is currently in active production status with RoHS3 compliance and unlimited moisture sensitivity rating. Substitute parts are identified when equivalent memory capacity, organization, and electrical specifications align within acceptable operational parameters, enabling design flexibility and supply chain alternatives.

Substiute Parts

11AA040T-I/MS

Microchip TechnologyIn Stock: 123311AA040T-I/MS Datasheet

Current PartRFQ

CAT24C04YI-G

Catalyst Semiconductor Inc.In Stock: 1512CAT24C04YI-G Datasheet

MFR RecommendedRFQ

CAT24C04YI-GT3

onsemiIn Stock: 74457CAT24C04YI-GT3 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 11AA040T-I/MS are qualified based on the following critical parameters: memory capacity (4Kbit), memory organization (512 x 8 bits), write cycle time (5ms), supply voltage range compatibility, and operating temperature range (-40°C ~ 85°C). The identified substitutes—CAT24C04YI-G and CAT24C04YI-GT3—maintain equivalent memory specifications and thermal performance. However, these substitutes employ I2C serial interface protocol rather than single-wire interface, representing a functional interface change that requires circuit-level design consideration. Both substitutes are surface mount devices in 8-TSSOP packaging and maintain RoHS3 compliance. Substitution is valid only when the application circuit supports I2C protocol implementation and the physical package footprint change from 8-MSOP to 8-TSSOP is accommodated in the PCB layout.

Parameter Comparison

Engineering Selection Recommendations

Selection between the main part and substitutes is determined by interface protocol requirements and PCB layout constraints. The 11AA040T-I/MS remains the primary choice for applications specifically designed around single-wire EEPROM interface architecture. CAT24C04YI-GT3 (onsemi) is preferred as a substitute when I2C protocol compatibility exists, offering unlimited moisture sensitivity rating (MSL 1) and verified programmability status, with highest inventory availability (74,400 pcs). CAT24C04YI-G (Catalyst Semiconductor Inc.) serves as an alternative I2C substitute with lower inventory levels and MSL 3 rating (168-hour moisture sensitivity limit). All three parts maintain active production status, RoHS3 compliance, and identical thermal operating ranges. Package footprint change from 8-MSOP to 8-TSSOP requires PCB redesign validation.

Frequently Asked Questions (FAQ)

Q: Can CAT24C04YI-G or CAT24C04YI-GT3 directly replace the 11AA040T-I/MS without circuit modification?

A: No. While memory capacity and electrical specifications are equivalent, the interface protocol differs fundamentally. The 11AA040T-I/MS uses single-wire protocol; the substitutes use I2C protocol. Circuit redesign is required to implement I2C communication logic.

Q: What is the primary difference between CAT24C04YI-G and CAT24C04YI-GT3?

A: Both parts are electrically identical 4Kbit I2C EEPROMs with 400 kHz operation. The primary differences are manufacturer (Catalyst Semiconductor Inc. vs. onsemi), moisture sensitivity level (MSL 3 vs. MSL 1), inventory availability, and packaging format (Bulk vs. Cut Tape & Digi-Reel).

Q: Are there package compatibility concerns when substituting?

A: Yes. The 11AA040T-I/MS uses 8-MSOP packaging (3.00mm width), while both substitutes use 8-TSSOP packaging (4.40mm width). PCB footprint redesign is necessary; the parts are not pin-compatible on existing layouts.

Q: Do all three parts meet the same compliance standards?

A: All three parts are RoHS3 compliant, EAR99 classified, and operate across -40°C to 85°C temperature range. MSL ratings differ: 11AA040T-I/MS and CAT24C04YI-GT3 have MSL 1 (unlimited); CAT24C04YI-G has MSL 3 (168-hour limit).

Q: Which substitute offers the best supply availability?

A: CAT24C04YI-GT3 (onsemi) provides the highest inventory with 74,400 pcs in stock, compared to 1,474 pcs for CAT24C04YI-G and 1,139 pcs for the original 11AA040T-I/MS.