Microchip Technology 93AA46-I/SN

Overview

93AA46-I/SN from Microchip Technology Inc. is a 1K-bit (128 × 8 or 64 × 16) low-voltage serial EEPROM with Microwire interface, ORG-pin-selectable memory organization, and 1.8V–5.5V single-supply operation. It delivers 70 µA typical active read current at 1.8V, 2 µA standby current, and supports industrial temperature range (−40°C to +85°C) in an 8-lead SOIC (SN) package. It is used for nonvolatile parameter storage in embedded control systems requiring low-power, reliable data retention.

For engineers reviewing the 93AA46-I/SN datasheet, 93AA46-I/SN pinout, 93AA46-I/SN application, or 93AA46-I/SN equivalent, key selection criteria include its 1.8V minimum operating voltage, self-timed erase/write cycles (4 ms/word), 1 million endurance cycles, >200-year data retention, and compatibility with 3-wire Microwire protocol in industrial-grade SOIC packaging.

Technical Context

The 93AA46-I/SN implements a synchronous 3-wire Microwire serial interface with CS, CLK, DI, and DO lines. Its memory array is configurable via the ORG pin to operate as either 128 × 8-bit or 64 × 16-bit organization, enabling flexible byte- or word-oriented access. All programming operations - including WRITE, ERASE, ERAL, and WRAL - are self-timed and include automatic ERAL before WRAL.

Power-on/off data protection inhibits programming until VCC exceeds 1.4V or falls below that threshold, and the device powers up in EWDS (Erase/Write Disable) mode. Ready/Busy status is signaled via the DO pin during erase/write cycles, supporting polling-based firmware synchronization without external timing components.

Key Specifications

Pinout & Package

8-lead SOIC (SN) package per JEDEC MS-012 standard, 150 mil body width, surface-mount compatible.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93AA46-I/SN, the 93AA46C-I/SN offers identical functionality with extended manufacturer support, while the AT25010B-MAU-T requires protocol adaptation and forfeits ORG-based memory flexibility and integrated erase-before-write assurance.

Availability

93AA46-I/SN is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration storage, and automotive body control module applications requiring stable component supply and long-term obsolescence management.

Supply support for 93AA46-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 memory solutions, headquartered in Chandler, Arizona, with global design, manufacturing, and sales operations.

The 93AA46-I/SN belongs to Microchip's legacy 93AA serial EEPROM product line, designed specifically for cost-sensitive, low-power embedded systems requiring simple 3-wire nonvolatile memory with industrial temperature tolerance and long data retention.

FAQ

What is the memory organization flexibility of the 93AA46-I/SN?

The 93AA46-I/SN supports dual memory configurations via the ORG pin: when tied to VSS, it operates as 128 × 8-bit (byte-addressable); when tied to VCC, it configures as 64 × 16-bit (word-addressable). This allows firmware to optimize for data width without hardware redesign. The 93AA46-I/SN maintains full instruction set compatibility in both modes, including READ, WRITE, ERASE, and WRAL commands tailored to the selected organization.

Does the 93AA46-I/SN require external timing components for erase or write operations?

No, the 93AA46-I/SN features fully self-timed erase and write cycles - no external capacitors, clocks, or delay loops are needed. Each operation (e.g., WRITE, ERAL, WRAL) initiates automatically on the falling edge of CS and completes internally. Typical times are 4 ms per word for WRITE/ERASE, 8 ms for ERAL, and 16 ms for WRAL. The 93AA46-I/SN signals completion via the DO pin (high = ready), enabling deterministic polling-based firmware control.

How does the 93AA46-I/SN protect against unintended writes during power transitions?

The 93AA46-I/SN incorporates hardware-level power-on/off data protection: programming modes are inhibited until VCC rises above 1.4V, and disabled again when VCC drops below that threshold. Additionally, the device powers up in EWDS (Erase/Write Disable) mode, requiring an explicit EWEN command before any ERASE or WRITE instruction executes. These dual safeguards prevent corruption during brown-out, cold start, or rapid power cycling - a critical feature verified in the 93AA46-I/SN's industrial temperature qualification.

What is the role of the NU pin on the 93AA46-I/SN SOIC package?

The NU (Not Utilized) pin on the 93AA46-I/SN is internally unconnected and serves no electrical function. Per Microchip's DS20067K datasheet, it may be left floating, tied to VSS, or tied to VCC based on PCB layout requirements - none affects device operation. This pin exists due to package standardization across the 93AA46/56/66 family and does not impact timing, power, or signal integrity. The 93AA46-I/SN's functional pins remain CS, CLK, DI, DO, VSS, ORG, and VCC.

Is the 93AA46-I/SN compatible with modern microcontrollers lacking native Microwire peripherals?

Yes - the 93AA46-I/SN's 3-wire Microwire interface can be implemented in firmware using GPIO-controlled bit-banging on any MCU, including those without dedicated Microwire hardware. Its protocol uses simple synchronous edge-triggered transfers (data sampled on CLK rising edge), no complex framing, and minimal timing constraints (e.g., TDIS = 100 ns at 1.8V). Many ARM Cortex-M, PIC, and RISC-V designs successfully drive the 93AA46-I/SN via software SPI-like routines, preserving full functionality of the 93AA46-I/SN without hardware dependency.