Microchip Technology 11AA020-I/MS

Overview

11AA020-I/MS from Microchip Technology is a 2 Kbit (256 × 8) serial EEPROM with UNI/O® single I/O bus interface, operating from 1.8V to 5.5V, featuring 16-byte page write buffer, 1 µA max standby current (I-temp), and Schmitt-trigger SCIO input for noise immunity in space-constrained industrial control and sensor calibration applications.

For engineers reviewing the 11AA020-I/MS datasheet, 11AA020-I/MS pinout, 11AA020-I/MS application, or 11AA020-I/MS equivalent, key selection criteria include its 1.8V low-voltage operation, Manchester-encoded UNI/O® timing compliance (10–100 kHz), STATUS register visibility (WIP/WEL/BP bits), block write protection (0%/25%/50%/100%), and MSOP-8 package compatibility with legacy 8-pin EEPROM footprints.

Technical Context

The 11AA020-I/MS implements a Manchester-encoded, master-controlled UNI/O® bus protocol over a single SCIO line, eliminating separate clock lines and reducing PCB routing complexity. Its internal re-synchronization circuitry tolerates ±0.50% frequency drift per byte and ±0.06 UI edge jitter, enabling robust communication across voltage/temperature variations without external timing components.

It integrates a current-limited, slope-controlled SCIO driver (±3 mA at 2.5V), on-chip high-voltage generator for EEPROM programming, and a nonvolatile STATUS register with write-enable latch and two block-protection bits (BP1/BP0). Write cycles are self-timed (max 10 ms), with automatic erase before write and 1,000,000 endurance cycles per page.

Key Specifications

Pinout & Package

11AA020-I/MS is packaged in an 8-lead MSOP (MS) package, measuring 3.0 mm × 3.0 mm × 1.0 mm, with gull-wing leads compatible with standard surface-mount reflow profiles. Pin 1 is marked by a dot or beveled corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C02C-SSHM-T and 24AA02E48-I/MS, the 11AA020-I/MS delivers lower pin count, superior noise immunity via Schmitt-trigger SCIO, real-time STATUS register access during writes, and guaranteed 1.8V operation - making it optimal for resource-constrained, electrically noisy, or ultra-low-voltage embedded systems.

Availability

11AA020-I/MS is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, automotive body control modules, consumer appliance settings, and portable diagnostic equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 11AA020-I/MS 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 11AA020-I/MS belongs to Microchip's UNI/O® Serial EEPROM family, designed specifically for space- and pin-constrained embedded systems requiring robust, low-voltage, single-wire nonvolatile storage with minimal firmware overhead.

FAQ

What is the UNI/O® bus interface used by the 11AA020-I/MS?

The 11AA020-I/MS uses Microchip's patented UNI/O® bus, a single-wire, Manchester-encoded serial interface where clock and data are combined on the SCIO line. This eliminates the need for a separate clock signal, reduces pin count to three (VCC, VSS, SCIO), and simplifies PCB layout. The 11AA020-I/MS supports bus frequencies from 10 kHz to 100 kHz and includes built-in re-synchronization to tolerate frequency drift and edge jitter.

Does the 11AA020-I/MS support 1.8V operation, and what are the implications?

Yes, the 11AA020-I/MS operates from 1.8V to 5.5V, with full functionality including read, write, and STATUS register access at 1.8V. This enables direct interfacing with modern ultra-low-power MCUs and sensors without level-shifting circuitry. At 1.8V, active current is 1 mA typical and standby current remains ≤1 µA, making the 11AA020-I/MS ideal for battery-powered applications such as portable diagnostics and wireless sensors.

How does the STATUS register in the 11AA020-I/MS improve system reliability?

The 11AA020-I/MS STATUS register provides real-time visibility into Write-In-Progress (WIP), Write-Enable Latch (WEL), and Block Protection (BP0/BP1) states. Crucially, it can be read *during* an internal write cycle - allowing firmware to poll WIP without halting other operations. This eliminates blind delays and enables responsive error recovery. The 11AA020-I/MS also supports continuous STATUS reads via MAK repetition, enabling tight timing control in safety-critical firmware.

What package options are available for the 11AA020-I/MS, and is the MSOP-8 pinout compatible with other EEPROMs?

The 11AA020-I/MS is offered in the 8-lead MSOP (MS) package, alongside PDIP, SOIC, TDFN, SOT-23, TO-92, and Chip Scale variants. The MSOP-8 footprint matches industry-standard 8-pin EEPROM packages (e.g., SOIC-8 pitch), but pin functions differ: pins 1–3 and 6–7 are NC, pin 4 is VSS, pin 5 is VCC, and pin 8 is SCIO. Therefore, while the physical outline is compatible, PCB layout must follow the 11AA020-I/MS-specific pinout - not generic SOIC-8 mappings.

Can the 11AA020-I/MS be used in automotive applications, and what is its temperature rating?

The 11AA020-I/MS is rated for Industrial temperature range (−40°C to +85°C), not Automotive (−40°C to +125°C). It is therefore suitable for under-hood-adjacent modules like body control units or cabin sensors where ambient temperature stays within I-temp limits, but not for direct engine-compartment placement. For full AEC-Q100 compliance and 125°C operation, Microchip's 11LC020-E/MS variant should be selected instead - the 11AA020-I/MS itself is not qualified for E-temp automotive use.