Microchip Technology 93AA46AT-I/SN

Overview

93AA46AT-I/SN from Microchip Technology Inc. is a 1K-bit (128 × 8) low-voltage serial EEPROM with Microwire-compatible 3-wire interface, 1.8–5.5 V supply range, and industrial temperature rating (–40°C to +85°C). It features self-timed erase/write cycles, automatic erase-all-before-write-all (ERAL/WRAL), and Ready/Busy status signaling via DO pin. Used for configuration storage in embedded controllers, sensor calibration data retention, and boot code parameter backup.

For engineers reviewing the 93AA46AT-I/SN datasheet, 93AA46AT-I/SN pinout, 93AA46AT-I/SN application, or 93AA46AT-I/SN equivalent, key selection criteria include its dedicated 8-bit organization (no ORG pin required), 1 million erase/write endurance, >200-year data retention, and SOIC-8 package compatibility with legacy PCB footprints.

Technical Context

This device implements a synchronous serial Microwire protocol with CS/CLK/DI/DO signals and no internal address counter reset on CS deassertion-enabling true sequential read across all 128 bytes. Its internal logic enforces power-on write protection below 1.5 V and requires explicit EWEN command before any erase or write operation.

The 93AA46AT-I/SN uses CMOS floating-gate technology with auto-erase prior to write, eliminating need for separate erase commands in most applications. All timing-including TWC (6 ms max write cycle), TPD (400 ns max output delay at 1.8 V), and TCSL (250 ns min CS low time)-is fully specified across the full 1.8–5.5 V VCC range and industrial temperature grade.

Key Specifications

Pinout & Package

8-pin SOIC (SN) package with standard 150-mil body width and 1.27 mm pitch; RoHS-compliant matte tin finish; pin 1 marked by laser dot or notch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC46A-I/SN, the 93AA46AT-I/SN extends low-voltage operation to 1.8 V while retaining identical pinout and firmware compatibility; versus AT25010B-SSHL-T, it preserves Microwire legacy support and adds deterministic ERAL/WRAL functionality critical for robust parameter initialization.

Availability

93AA46AT-I/SN is available at Aetrix Electronics and suitable for industrial sensor calibration, embedded controller configuration, and motor drive boot parameter storage requiring stable component supply across multi-year production cycles.

Supply support for 93AA46AT-I/SN 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 Inc. is a leading provider of microcontroller, analog, and Flash-IP solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 93XX46 series was designed specifically for cost-sensitive, low-power nonvolatile memory applications in industrial and automotive systems-emphasizing reliability, wide VCC tolerance, and Microwire interoperability.

FAQ

What is the memory organization of the 93AA46AT-I/SN?

The 93AA46AT-I/SN is a fixed 128 × 8-bit (1 Kbit) EEPROM with no ORG pin-unlike C-variants, it does not support x16 mode. This eliminates external configuration logic and ensures deterministic 8-bit data framing in all applications. Its architecture delivers consistent 8-bit reads/writes without software mode switching.

Does the 93AA46AT-I/SN require an external pull-up resistor on the DO pin?

Yes, the 93AA46AT-I/SN DO pin is open-drain and requires an external pull-up resistor (typically 4.7 kΩ to VCC) to assert logic high during Ready/Busy status polling or data output. Without it, DO remains indeterminate during status checks, risking incorrect busy-state interpretation and premature command execution.

How does the 93AA46AT-I/SN handle power loss during a write cycle?

The 93AA46AT-I/SN incorporates hardware power-loss protection: its internal POR circuit blocks write operations when VCC drops below 1.5 V, preventing partial writes or memory corruption. Combined with auto-erase-before-write, this ensures data integrity even during abrupt brownouts common in industrial power environments.

Can the 93AA46AT-I/SN be used with a microcontroller that only supports SPI?

No-the 93AA46AT-I/SN uses a Microwire-compatible 3-wire interface (CS/CLK/DI/DO), not SPI. While both are synchronous serial protocols, Microwire lacks MOSI/MISO separation and uses bidirectional DO. Direct SPI hardware cannot drive it without bit-banged GPIO emulation matching Microwire timing (e.g., TCKH ≥200 ns at 1.8 V).

What is the minimum CS low time required between commands on the 93AA46AT-I/SN?

The 93AA46AT-I/SN requires a minimum Chip Select low time (TCSL) of 250 ns between consecutive instructions, regardless of VCC voltage. This ensures internal state machine reset and prevents command overlap or misinterpretation-critical for reliable operation in noisy industrial environments with fast clock edges.