Microchip Technology 11AA020T-I/TT

Overview

11AA020T-I/TT from Microchip Technology Inc. is a 2 Kbit (256 × 8) serial EEPROM using the UNI/O® single I/O bus interface, operating from 1.8V to 5.5V with 1 µA max standby current and 1 mA typical active current. It features Manchester-encoded communication at up to 100 kbps, 16-byte page write buffer, and built-in write protection for industrial temperature range (–40°C to +85°C). It is commonly used in space-constrained embedded systems for parameter storage, calibration data retention, and firmware configuration.

For engineers reviewing the 11AA020T-I/TT datasheet, 11AA020T-I/TT pinout, 11AA020T-I/TT application, or 11AA020T-I/TT equivalent, key selection considerations include its 3-lead SOT-23 package, UNI/O® protocol compatibility, 1.8V minimum VCC, 16-byte page buffer size, and block-level write protection granularity (none/¼/½/all array).

Technical Context

The 11AA020T-I/TT implements a Manchester-encoded, master-controlled UNI/O® bus with SCIO as the sole bidirectional signal line. Its internal architecture includes a status register with WIP and WEL bits, a 16-byte page latch, and Schmitt-trigger input with slope-controlled output to suppress ground bounce.

It supports self-timed byte/page writes with 5–10 ms duration, automatic erase-before-write, and re-synchronization logic tolerant of ±0.5% frequency drift per byte and ±0.06 UI edge jitter. The device enters Standby mode after NoMAK/SAK termination or a TSTBY ≥600 µs high pulse on SCIO.

Key Specifications

Pinout & Package

11AA020T-I/TT is housed in a 3-lead SOT-23 package (TT suffix), with SCIO, VCC, and VSS terminals. No NC pins are present in this variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 11AA020T-I/TT, the 11LC020T-I/TT trades 1.8V compatibility for identical packaging and protocol, while the 24AA02E48-I/OT replaces UNI/O® simplicity with I²C flexibility and multi-device support - neither offers pin-to-pin or functional drop-in replacement.

Availability

11AA020T-I/TT is available at Aetrix Electronics and suitable for industrial control systems, medical diagnostics equipment, and IoT edge nodes requiring stable component supply, long-life data retention, and minimal PCB footprint.

Supply support for 11AA020T-I/TT 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 U.S.-based semiconductor company specializing in microcontrollers, analog devices, and memory products, with emphasis on embedded control and low-power solutions.

The 11AAxxx family was designed specifically for ultra-low-pin-count, low-voltage embedded systems needing reliable nonvolatile storage without sacrificing board area - targeting applications where every GPIO and mm² matters.

FAQ

What is the UNI/O® interface used by the 11AA020T-I/TT, and how does it differ from I²C or SPI?

The 11AA020T-I/TT uses Microchip's patented UNI/O® bus - a single-wire, Manchester-encoded serial interface that combines clock and data on the SCIO line. Unlike I²C (2-wire, open-drain) or SPI (4-wire, separate clock/MOSI/MISO/CS), UNI/O® requires only one I/O pin plus VCC/VSS, reducing MCU pin count and PCB routing complexity. It operates at up to 100 kbps and relies on master-controlled timing with built-in re-synchronization to tolerate frequency drift and jitter.

Does the 11AA020T-I/TT support 1.8V operation, and what are the implications for low-power designs?

Yes, the 11AA020T-I/TT supports VCC from 1.8V to 5.5V, enabling direct connection to 1.8V logic families without level shifters. At 1.8V, its standby current remains ≤1 µA (max) and active read current is ≤1 mA (typical), making it ideal for battery-powered applications like wearables and remote sensors where energy efficiency and voltage scalability are critical design constraints.

How does the page write buffer function in the 11AA020T-I/TT, and what happens if a write crosses a page boundary?

The 11AA020T-I/TT includes a 16-byte page write buffer that accepts up to 16 sequential bytes before initiating the internal write cycle. If a write command attempts to cross a 16-byte physical page boundary (e.g., writing byte 15 then byte 16 of page 0x30–0x3F), the address pointer wraps to the start of the same page (0x30), overwriting previously loaded data. Application firmware must enforce page-aligned writes or split multi-page operations manually.

What write protection mechanisms does the 11AA020T-I/TT provide, and how are they configured?

The 11AA020T-I/TT provides dual-layer write protection: hardware-based (power-on reset clears write enable latch) and software-configurable block protection via BP0/BP1 bits in the STATUS register. These bits - set using the WRSR command - lock 0%, 25%, 50%, or 100% of the memory array. Protection is nonvolatile and persists through power cycles, preventing accidental or malicious overwrites of critical calibration or configuration data.

Can the 11AA020T-I/TT be used in automotive applications, and what is its temperature rating?

No, the 11AA020T-I/TT is rated for Industrial temperature range only (–40°C to +85°C) and carries the "I" suffix. Automotive-grade variants (e.g., 11LC020T-E/TT) exist with "E" suffix and –40°C to +125°C qualification, but the 11AA020T-I/TT is not AEC-Q100 qualified. For automotive use, engineers must select an E-temp part or verify full qualification documentation before deployment in vehicle subsystems.