93C66-E/SN EEPROM Memory IC Equivalent & Substitute Parts

Part Overview

The 93C66-E/SN is a 4Kbit EEPROM memory IC manufactured by Microchip Technology, featuring Microwire serial interface protocol and 2 MHz clock frequency. This non-volatile memory device is designed for applications requiring persistent data storage in embedded systems and industrial equipment. The part is currently in active production status with 2400 units available in new original inventory.

Substitute parts are necessary when the primary part experiences supply constraints, when specific packaging or temperature grade requirements differ from the original specification, or when design flexibility allows for compatible alternatives from qualified manufacturers.

Substiute Parts

93C66-E/SN

Microchip TechnologyIn Stock: 243793C66-E/SN Datasheet

Current PartRFQ

M93C66-RMN3TP/K

STMicroelectronicsIn Stock: 16005M93C66-RMN3TP/K Datasheet

MFR RecommendedRFQ

M93C66-WMN6P

STMicroelectronicsIn Stock: 1628M93C66-WMN6P Datasheet

MFR RecommendedRFQ

M93C66-WMN6TP

STMicroelectronicsIn Stock: 35132M93C66-WMN6TP Datasheet

MFR RecommendedRFQ

M93C76-RMN3TP/K

STMicroelectronicsIn Stock: 5031M93C76-RMN3TP/K Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 93C66-E/SN is determined by the following critical parameters:

Core Compatibility Requirements:

• Memory Size: 4Kbit (fixed requirement)
• Memory Interface: Microwire protocol (fixed requirement)
• Package / Case: 8-SOIC form factor (fixed requirement)
• Clock Frequency: 2 MHz (fixed requirement)
• Memory Organization: 512 x 8, 256 x 16 (fixed requirement)

Allowable Variation Parameters:

• Voltage Supply Range: Substitute parts may have extended or different supply voltage ranges, provided the original operating voltage (4.5V ~ 5.5V) falls within the substitute's specification
• Operating Temperature Range: Substitute parts may support extended temperature ranges beyond the original -40°C ~ 125°C specification
• Write Cycle Time: Substitute parts may have different write cycle times (original: 2ms; substitutes: 5ms) without affecting functional compatibility
• Packaging Format: Cut Tape, Tube, or Tape & Reel formats are interchangeable for the same electrical component
• Manufacturer: STMicroelectronics M93C66 and M93C76 series parts meet all core compatibility requirements

All substitute parts listed maintain identical memory capacity, interface protocol, package geometry, and clock frequency specifications.

Parameter Comparison

Engineering Selection Recommendations

Primary Selection (Highest Compatibility): M93C66-WMN6TP is the preferred substitute, offering the largest available inventory (35,100 units), verified programmability status, and extended supply voltage range (2.5V ~ 5.5V) that encompasses the original 4.5V ~ 5.5V specification. This part maintains the original operating temperature range of -40°C ~ 125°C and is available in Cut Tape & Digi-Reel packaging format.

Alternative Selection (Extended Temperature Range): M93C66-RMN3TP/K and M93C76-RMN3TP/K both provide AEC-Q100 automotive qualification and extended supply voltage range (1.8V ~ 5.5V). These parts maintain the full -40°C ~ 125°C operating temperature specification. M93C66-RMN3TP/K offers higher inventory availability (15,924 units) compared to M93C76-RMN3TP/K (4,952 units).

Temperature-Constrained Applications: M93C66-WMN6P is suitable for applications with maximum operating temperature of 85°C, offering verified programmability and Tube packaging format with 1,543 units in stock.

Inventory Availability Consideration: When supply of the original 93C66-E/SN (2,400 units) is insufficient, M93C66-WMN6TP provides the highest stock level at 35,100 units, followed by M93C66-RMN3TP/K at 15,924 units.

Frequently Asked Questions (FAQ)

Q: Can M93C66-WMN6TP directly replace 93C66-E/SN in existing designs? A: Yes. Both parts share identical memory capacity (4Kbit), interface protocol (Microwire), clock frequency (2 MHz), package geometry (8-SOIC), and memory organization (512 x 8, 256 x 16). The extended supply voltage range of M93C66-WMN6TP (2.5V ~ 5.5V) fully encompasses the original specification (4.5V ~ 5.5V). Pin-to-pin compatibility is maintained.

Q: What is the significance of the 2ms versus 5ms write cycle time difference? A: The write cycle time specifies the duration required to complete a single word or page write operation. The original 93C66-E/SN requires 2ms per write cycle, while STMicroelectronics substitutes require 5ms. This difference does not affect functional compatibility but may impact applications with strict write timing requirements. Designs with write operation intervals exceeding 5ms experience no performance degradation.

Q: Are the M93C76-RMN3TP/K and M93C66-RMN3TP/K interchangeable? A: Yes, for this 4Kbit memory application. Both parts meet identical electrical and mechanical specifications for memory size, interface, package, and operating parameters. The M93C76 designation indicates a different base product line from STMicroelectronics, but the specific variants listed (M93C76-RMN3TP/K) are functionally equivalent to M93C66-RMN3TP/K for 4Kbit Microwire EEPROM applications.

Q: Which substitute part is recommended for automotive applications? A: M93C66-RMN3TP/K and M93C76-RMN3TP/K both carry AEC-Q100 automotive qualification. These parts are suitable for automotive-grade applications requiring extended temperature range (-40°C ~ 125°C) and extended supply voltage range (1.8V ~ 5.5V). M93C66-RMN3TP/K offers higher inventory availability.

Q: Does packaging format (Cut Tape, Tube, Tape & Reel) affect electrical performance? A: No. Packaging format affects only the physical delivery and handling method. Cut Tape (CT) & Digi-Reel, Tube, and Tape & Reel formats contain electrically identical components. Selection should be based on assembly equipment compatibility and procurement requirements.

Q: Are all substitute parts ROHS3 compliant? A: Yes. All listed substitute parts (M93C66-RMN3TP/K, M93C66-WMN6P, M93C66-WMN6TP, M93C76-RMN3TP/K) maintain ROHS3 compliance status, matching the original 93C66-E/SN specification.