Microchip Technology AT93C66A-10PI-1.8

Overview

AT93C66A-10PI-1.8 from Microchip Technology (formerly Atmel) is a 4-kbit serial EEPROM with 3-wire interface, configurable as 512 × 8 or 256 × 16 organization via ORG pin, operating at 1.8V–5.5V supply, and rated for industrial temperature (−40°C to +85°C) in 8-lead PDIP package. It supports self-timed write cycles (max 10 ms), 2 MHz clock rate at 5V, and delivers 1 million write cycles with 100-year data retention.

For engineers reviewing the AT93C66A-10PI-1.8 datasheet, AT93C66A-10PI-1.8 pinout, AT93C66A-10PI-1.8 application, or AT93C66A-10PI-1.8 equivalent, key selection considerations include low-voltage operation down to 1.8V, user-selectable memory organization, sequential read capability, READY/BUSY status reporting via DO pin, and automotive-grade reliability with extended temperature support.

Technical Context

The AT93C66A-10PI-1.8 implements a synchronous 3-wire serial interface (CS, SK, DI/DO) with instruction-based command set including READ, WRITE, ERASE, EWEN, EWDS, ERAL, and WRAL. Its internal organization is dynamically selected by the ORG pin state-high for 256 × 16, low for 512 × 8-and supports dummy-bit-prefixed output during read operations.

Write and erase operations are fully self-timed with no external timing control required; the DO pin provides real-time READY/BUSY status when CS is asserted after instruction initiation. The device enters Erase/Write Disable (EWDS) state on power-up and requires explicit EWEN instruction before programming, ensuring robust data integrity in noise-prone environments.

Key Specifications

Pinout & Package

AT93C66A-10PI-1.8 is housed in an 8-lead PDIP (Plastic Dual Inline Package), 0.300" wide body, with standard through-hole mounting and JEDEC MS-001 compliant dimensions.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar serial EEPROM applications.

Compared with M95M02-DRMN6TP/K and STK12C68-55I, the AT93C66A-10PI-1.8 offers unique 3-wire simplicity and hardware-configurable organization, making it optimal for cost-sensitive, space-constrained designs requiring minimal GPIO usage and deterministic low-voltage operation - without sacrificing endurance or retention.

Availability

AT93C66A-10PI-1.8 is available at Aetrix Electronics and suitable for industrial sensor calibration, consumer remote control memory, automotive body control modules, and medical diagnostic equipment setup requiring stable component supply and long-term lifecycle assurance.

Supply support for AT93C66A-10PI-1.8 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology is a global semiconductor company specializing in microcontrollers, analog components, and memory solutions, with broad industrial and automotive qualification expertise.

The AT93C66A-10PI-1.8 belongs to Microchip's legacy Atmel serial EEPROM product line, designed specifically for low-pin-count, low-power, and high-reliability nonvolatile storage in resource-constrained embedded systems.

FAQ

What is the memory organization of AT93C66A-10PI-1.8 and how is it configured?

The AT93C66A-10PI-1.8 offers user-selectable organization: 512 × 8 bits when the ORG pin is grounded, or 256 × 16 bits when ORG is tied to VCC. This hardware-level configuration avoids firmware overhead and ensures deterministic addressing. Unconnected ORG defaults to x16 mode due to internal 1 MΩ pull-up, though this behavior is not supported on 1.8V-only variants like the AT93C66A-10PI-1.8.

Does AT93C66A-10PI-1.8 support sequential read operations?

Yes, the AT93C66A-10PI-1.8 supports sequential read: after initiating a READ instruction, holding CS active allows automatic address increment and continuous data streaming from consecutive memory locations. No dummy bit is inserted between words, enabling efficient bulk reads - a key advantage over basic byte-read-only EEPROMs.

What is the maximum clock frequency for AT93C66A-10PI-1.8 at 1.8V supply?

At VCC = 1.8V, the AT93C66A-10PI-1.8 supports a maximum SK clock frequency of 0.25 MHz, as specified in its AC characteristics table. This reduced speed ensures reliable timing margin under low-voltage conditions while maintaining full functionality including READ, WRITE, and status polling via DO.

How does AT93C66A-10PI-1.8 indicate write completion status?

The AT93C66A-10PI-1.8 uses the DO pin to report READY/BUSY status: after initiating a WRITE or ERASE instruction, asserting CS high (following ≥250 ns low time) causes DO to output '0' during programming and '1' upon completion. This eliminates need for fixed delays and enables precise host synchronization without polling overhead.

Is AT93C66A-10PI-1.8 pin-compatible with AT93C66A-10PI-2.7?

Yes, AT93C66A-10PI-1.8 and AT93C66A-10PI-2.7 share identical 8-lead PDIP packaging, pinout, and functional interface. The sole difference is the minimum operating voltage: 1.8V vs. 2.7V. Both support the same instruction set, timing, and organization control - allowing direct substitution in 1.8V–5.5V systems, but not in 2.7V-only designs.