Microchip Technology 93AA76/SN

Overview

93AA76/SN from Microchip Technology Inc. is an 8K-bit (1024 × 8 or 512 × 16) low-voltage serial EEPROM with Microwire interface, operating down to 1.8V, featuring self-timed erase/write cycles, ORG-pin-selectable memory organization, and Program Enable (PE) pin for hardware write protection. It delivers 1 mA typical active current and 5 µA standby current at 3.0V, and is used in embedded system configuration storage where nonvolatile, low-power, and serial interface constraints apply.

For engineers reviewing the 93AA76/SN datasheet, 93AA76/SN pinout, 93AA76/SN application, or 93AA76/SN equivalent, this page provides verified technical context, validated pin functions, confirmed memory architecture behavior, real-world application mappings, and two documented alternative parts with explicit functional and packaging differences.

Technical Context

The 93AA76/SN implements a synchronous 3-wire Microwire-compatible serial interface using CS, CLK, and bidirectional DI/DO lines, with ORG pin selection between x8 (1024 × 8) and x16 (512 × 16) memory configurations. It uses CMOS technology with internal power-on/off data protection circuitry and automatic ERAL before WRAL execution.

Operation requires EWEN instruction to enable programming; all erase/write cycles are self-timed (3 ms per word typical), with DO pin providing Ready/Busy status during those operations. The device supports sequential read, block-level erase (ERAL), and full-array write (WRAL), with guaranteed 1,000,000 erase/write cycles and >200-year data retention.

Key Specifications

Pinout & Package

8-pin SOIC (SN) package, 150 mil body width, JEDEC MS-012 compliant, with gull-wing leads and Pb-free matte tin plating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93AA76/SN, the 93AA76C/SN offers identical functionality with improved ESD tolerance and lifecycle support, while the AT25080B-MAHL-T trades Microwire compatibility and ORG flexibility for higher-speed SPI access - making it suitable only when interface and configurability requirements align.

Availability

93AA76/SN is available at Aetrix Electronics and suitable for industrial sensor calibration storage, consumer appliance configuration memory, and embedded controller boot parameter storage requiring stable component supply and long-term obsolescence management.

Supply support for 93AA76/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, mixed-signal, analog, and Flash-IP solutions, headquartered in Chandler, Arizona, with global design, manufacturing, and sales operations.

The 93AA76/SN belongs to Microchip's legacy Microwire EEPROM product line, designed specifically for cost-sensitive, low-power embedded systems requiring simple 3-wire nonvolatile storage without SPI hardware dependency.

FAQ

What is the memory organization of the 93AA76/SN and how is it selected?

The 93AA76/SN supports two memory organizations: 1024 × 8 bits (x8) or 512 × 16 bits (x16), selected by the ORG pin. When ORG is tied to VSS (ground), the x8 mode is active; when tied to VCC, the x16 mode is active. An internal pull-up resistor defaults ORG to VCC, so x16 is selected if the pin is left unconnected. This selection determines address width and data bus width during READ/WRITE operations and is fixed at power-up.

Does the 93AA76/SN require external timing components for erase or write operations?

No, the 93AA76/SN does not require external timing components. All erase and write operations - including individual word, ERAL (Erase All), and WRAL (Write All) - are fully self-timed. Once the final address or data bit is clocked in, the device internally manages the programming cycle duration (e.g., 3 ms per word typical, 15 ms max for ERAL, 30 ms max for WRAL), and signals completion via the DO pin's Ready/Busy status.

How does the Program Enable (PE) pin function on the 93AA76/SN?

The PE pin on the 93AA76/SN provides hardware-level write protection. When PE is tied to VSS, all erase and write functions are disabled regardless of EWEN instruction state. When PE is floated or tied to VCC, programming is enabled - and must still be preceded by an EWEN command. An internal pull-up ensures programming capability if PE is left unconnected, making it fail-safe for default-write-enable configurations.

What is the maximum clock frequency supported by the 93AA76/SN across its voltage range?

Maximum clock frequency for the 93AA76/SN depends on VCC: 3 MHz for VCC = 4.5–6.0 V, 2 MHz for VCC = 2.5–4.5 V, and 1 MHz for VCC = 1.8–2.5 V. These limits ensure reliable setup/hold timing margins per AC specifications (e.g., TDIS, TCKH, TCKL) and are enforced by the device's internal timing logic - exceeding them may result in command misinterpretation or incomplete transfers.

Is the 93AA76/SN suitable for new designs, and what is the recommended replacement?

No - the 93AA76/SN is explicitly marked "Not recommended for new designs" in its official datasheet (DS21130F). Microchip recommends migrating to the 93AA76C/SN, a pin-compatible revision with enhanced ESD performance (6 kV HBM), updated process technology, and continued long-term availability. The 93AA76C/SN maintains identical electrical, timing, and functional specifications while offering improved robustness and supply chain support.