AT93C66-10PI EEPROM Equivalent & Substitute Parts

Part Overview

The AT93C66-10PI is a 4Kbit non-volatile EEPROM memory IC manufactured by Microchip Technology, featuring a 3-Wire Serial interface and 2 MHz clock frequency in an 8-PDIP through-hole package. This device is classified as obsolete, making equivalent substitute parts necessary for new designs and production continuity. The part operates across a 4.5V to 5.5V supply range with a 10ms write cycle time and supports memory organization of 512 x 8 or 256 x 16 bits.

Substiute Parts

AT93C66-10PI

Microchip TechnologyIn Stock: 48691AT93C66-10PI 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 is determined by the following critical parameters:

• Memory Capacity: 4Kbit capacity must be maintained
• Memory Organization: 512 x 8 or 256 x 16 bit configuration
• Package Compatibility: 8-DIP through-hole form factor with 0.300" (7.62mm) pitch
• Interface Protocol: Serial communication protocol compatibility (3-Wire Serial or Microwire)
• Supply Voltage Range: Operating voltage envelope must encompass or exceed 4.5V ~ 5.5V
• Operating Temperature Range: -40°C ~ 85°C minimum requirement
• Memory Type: Non-volatile EEPROM technology

The 93AA66C-I/P qualifies as a direct substitute based on matching memory capacity, organization, package type, and operating temperature range. Interface protocol differences (Microwire vs. 3-Wire Serial) are compatible at the functional level for this memory category.

Parameter Comparison

Engineering Selection Recommendations

The 93AA66C-I/P is the qualified substitute for AT93C66-10PI applications. Selection should be based on the following factors:

Product Status: The AT93C66-10PI is obsolete, whereas the 93AA66C-I/P maintains active production status, ensuring long-term availability and supply chain continuity.

Compliance: The 93AA66C-I/P is ROHS3 compliant and REACH unaffected, meeting modern regulatory requirements. The original AT93C66-10PI is RoHS non-compliant.

Performance Characteristics: The 93AA66C-I/P provides improved specifications including faster clock frequency (3 MHz vs. 2 MHz), reduced write cycle time (6ms vs. 10ms), and extended supply voltage range (1.8V ~ 5.5V vs. 4.5V ~ 5.5V).

Package and Pinout: Both devices share identical 8-DIP through-hole packaging, enabling direct physical replacement without PCB redesign.

Frequently Asked Questions (FAQ)

Q: Can the 93AA66C-I/P directly replace the AT93C66-10PI without firmware changes?

A: Physical replacement is possible due to identical package and pinout. However, interface protocol differences (Microwire vs. 3-Wire Serial) require verification of controller compatibility. Consult device datasheets for protocol-level signal timing and sequencing requirements.

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

A: Both are serial communication protocols for EEPROM devices. 3-Wire Serial and Microwire differ in signal timing, instruction set, and protocol sequencing. Compatibility depends on the host controller's capability to support the substitute device's protocol.

Q: Does the 93AA66C-I/P support the same memory organization as the AT93C66-10PI?

A: Yes. Both devices support 512 x 8 and 256 x 16 bit memory organization, maintaining functional equivalence for data storage capacity and access patterns.

Q: Are there supply voltage considerations when substituting these parts?

A: The 93AA66C-I/P operates across 1.8V ~ 5.5V, providing broader voltage compatibility than the AT93C66-10PI (4.5V ~ 5.5V). Existing 5V designs require no voltage adjustment. Lower voltage applications benefit from the extended range of the substitute.

Q: What is the significance of the improved write cycle time in the 93AA66C-I/P?

A: The 93AA66C-I/P reduces write cycle time from 10ms to 6ms, enabling faster data programming operations. This improvement does not affect backward compatibility but may reduce overall system write latency in applications performing frequent memory updates.

Q: Is the through-hole 8-DIP package still available for new designs?

A: The 93AA66C-I/P is available in 8-PDIP through-hole packaging with active production status, confirming continued availability for legacy and new through-hole based designs.