Microchip Technology 93AA46AT-I/OT

Overview

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

For engineers reviewing the 93AA46AT-I/OT datasheet, 93AA46AT-I/OT pinout, 93AA46AT-I/OT application, or 93AA46AT-I/OT equivalent, key selection criteria include its SOT-23-6 package, 8-bit fixed organization (no ORG pin), 1M endurance cycles, >200-year data retention, and compatibility with low-power battery-backed systems requiring nonvolatile memory with minimal footprint.

Technical Context

The 93AA46AT-I/OT implements a synchronous serial Microwire protocol using CS, CLK, and DI/DO lines - no ORG pin required due to fixed 8-bit organization. Communication begins with a Start bit (CS high + DI high on CLK rising edge), followed by opcode, 7-bit address, and 8-bit data for WRITE or READ operations.

Its internal architecture includes an address decoder, mode decode logic, and output buffer driving DO during read or Ready/Busy polling. Erase/write operations are fully self-timed (6 ms typical), with VCC brown-out protection activating below 1.5V and EWEN/EWDS commands enabling/disabling programming to prevent accidental writes.

Key Specifications

Pinout & Package

93AA46AT-I/OT is housed in a Pb-free 6-lead SOT-23 package (JEDEC MO-178AA), measuring 2.9 mm × 1.6 mm × 1.1 mm, optimized for space-constrained PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC46AT-I/OT, the 93AA46AT-I/OT extends low-voltage operation to 1.8V while retaining identical pinout and command structure; versus AT25010B-MAHL-T, it offers tighter timing control via DO-based status signaling and reduced pin count - critical for GPIO-constrained microcontrollers.

Availability

93AA46AT-I/OT is available at Aetrix Electronics and suitable for industrial automation, IoT edge node design, and consumer appliance development requiring stable component supply, long-term manufacturability, and RoHS-compliant packaging.

Supply support for 93AA46AT-I/OT 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 microcontrollers, analog devices, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 93AAxx series was designed specifically for cost-sensitive, space-constrained embedded systems needing reliable, low-power serial EEPROM with Microwire compatibility and robust data integrity features.

FAQ

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

The 93AA46AT-I/OT has a fixed 128 × 8-bit organization - meaning it provides 128 bytes of addressable memory with 8-bit-wide data access. Unlike 'C' variants, it does not feature an ORG pin and therefore does not support 16-bit mode. This simplifies design by eliminating external configuration logic and ensures consistent byte-oriented data handling in the 93AA46AT-I/OT.

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

Yes, the 93AA46AT-I/OT requires an external pull-up resistor on the DO pin to ensure valid logic-high levels during Ready/Busy status polling and read operations. The DO pin is tri-state and does not drive high actively; a typical 4.7 kΩ pull-up to V_CC is recommended. This is essential for reliable status detection, especially when using the DO pin to monitor erase/write completion in the 93AA46AT-I/OT.

What is the minimum V_CC level that prevents accidental writes in the 93AA46AT-I/OT?

The 93AA46AT-I/OT incorporates hardware-level write protection that activates when V_CC falls below approximately 1.5 V. Below this threshold, all erase and write instructions are inhibited - preventing data corruption during power-up, power-down, or brown-out conditions. This built-in protection is a key reliability feature of the 93AA46AT-I/OT and requires no firmware intervention.

Can the 93AA46AT-I/OT be used with a 1.8V microcontroller I/O interface?

Yes, the 93AA46AT-I/OT is fully compatible with 1.8V microcontrollers: its V_CC range is 1.8–5.5V, and its input thresholds (VIH1 = 2.0V min at V_CC ≥2.7V; VIH2 = 0.7×V_CC at V_CC <2.7V) ensure reliable recognition of 1.8V logic-high signals. This makes the 93AA46AT-I/OT ideal for modern ultra-low-power embedded systems where mixed-voltage interfacing is common.

How does the 93AA46AT-I/OT handle sequential reads?

The 93AA46AT-I/OT supports automatic sequential read: after issuing a READ command with an initial address, holding CS high causes the internal address counter to increment automatically, outputting consecutive memory locations on DO without retransmitting the opcode or address. This reduces command overhead and accelerates bulk data retrieval - a valuable capability in firmware update verification or sensor log streaming using the 93AA46AT-I/OT.