Microchip Technology 11AA160-I/MS

Overview

11AA160-I/MS from Microchip Technology is a 16 Kbit (2,048 × 8) serial EEPROM with UNI/O® single I/O bus interface, operating from 1.8V to 5.5V, featuring 16-byte page write buffer, Schmitt-trigger SCIO input, and 1 µA max standby current at I-temp (–40°C to +85°C). It is used in space-constrained embedded systems for nonvolatile parameter storage in sensor calibration, firmware configuration, and power-management settings.

For engineers reviewing the 11AA160-I/MS datasheet, 11AA160-I/MS pinout, 11AA160-I/MS application, or 11AA160-I/MS equivalent, key selection considerations include its 1.8V low-voltage operation, 100 kbps UNI/O® bit rate, 1 µA standby current, 16-byte page buffer, and MSOP-8 package compatibility with legacy SOIC footprints.

Technical Context

The 11AA160-I/MS implements Manchester-encoded UNI/O® protocol over a single bidirectional SCIO line, eliminating need for separate clock and data lines. Its internal timing recovery circuitry synchronizes to master clock period during start header and re-synchronizes on each MAK edge to tolerate ±0.50% frequency drift per byte and ±0.06 UI input jitter.

It integrates a write-enable latch, STATUS register (WIP/WEL/BP bits), and block protection logic enabling selective 0%, 25%, 50%, or 100% array write lock. Internal high-voltage generator enables self-timed erase/write cycles without external VPP.

Key Specifications

Pinout & Package

11AA160-I/MS is packaged in 8-lead MSOP (MS) with exposed pad, pin-compatible with SOIC-8 but occupying ~50% board area. Pin 1 = SCIO, Pin 2 = VSS, Pin 3 = NC, Pin 4 = NC, Pin 5 = NC, Pin 6 = NC, Pin 7 = NC, Pin 8 = VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 11LC160-I/MS, the 11AA160-I/MS enables true 1.8V operation and lower standby current, while 24AA160-I/MS trades UNI/O®'s pin efficiency for broader ecosystem support and faster 400 kHz I²C speeds - selection hinges on voltage margin, pin count constraints, and firmware driver availability.

Availability

11AA160-I/MS is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, and automotive body control modules requiring stable component supply across extended product lifecycles.

Supply support for 11AA160-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 U.S.-based semiconductor manufacturer specializing in microcontrollers, analog devices, and memory products for embedded control applications.

The 11AA160-I/MS belongs to Microchip's UNI/O® serial EEPROM family, designed specifically for ultra-low-pin-count systems where board space and GPIO scarcity constrain traditional serial interfaces.

FAQ

What is the minimum supply voltage required for reliable operation of the 11AA160-I/MS?

The 11AA160-I/MS operates reliably down to 1.8V across the full industrial temperature range (–40°C to +85°C). Below 2.5V, the input threshold shifts to 0.2×VCC for VIL and 0.3×VCC for VIH to maintain noise margin. This 1.8V capability enables direct integration with Li-ion coin cells and low-power MCUs without level-shifting circuitry - a key differentiator from 2.5V-only alternatives like the 11LC160-I/MS.

How does the UNI/O® interface of the 11AA160-I/MS differ from standard I²C or SPI protocols?

The 11AA160-I/MS uses Microchip's patented UNI/O® protocol, which combines clock and data onto a single bidirectional SCIO line using Manchester encoding - eliminating separate clock, data-in, and data-out signals required by SPI or I²C. Unlike I²C, it needs no pull-up resistors; unlike SPI, it requires only one GPIO. This reduces routing complexity, saves PCB layers, and simplifies firmware bit-banging - making the 11AA160-I/MS ideal for pin-constrained microcontrollers.

Can the 11AA160-I/MS be used in automotive applications?

The 11AA160-I/MS is rated for Industrial temperature (–40°C to +85°C) only and is not qualified for Automotive (AEC-Q100) use. For automotive body electronics requiring –40°C to +125°C operation, Microchip offers the 11LC160-E/MS variant - same pinout and UNI/O® interface but with extended temperature grade and automotive qualification. The 11AA160-I/MS itself must not be deployed in under-hood or safety-critical automotive systems.

What protection mechanisms prevent unintended writes to the 11AA160-I/MS memory array?

The 11AA160-I/MS employs three layered protections: (1) a volatile write-enable latch (WEL) that must be set via WREN command before any write; (2) nonvolatile block protection (BP0/BP1 bits) allowing 0%, 25%, 50%, or 100% array lock; and (3) hardware power-on write protection that resets WEL at POR/BOR. These ensure that accidental writes - whether from firmware bugs, noise, or brownout conditions - cannot corrupt stored data without explicit, multi-step enable sequences.

Is the MSOP-8 package of the 11AA160-I/MS compatible with standard SOIC-8 footprints?

No, the 11AA160-I/MS in MSOP-8 (package code "MS") has a 3 mm × 3 mm body with 0.65 mm lead pitch, whereas standard SOIC-8 measures 3.9 mm × 4.9 mm with 1.27 mm pitch. Though both are 8-lead surface-mount packages, they are not footprint-compatible. However, the MSOP-8 package is pin-to-pin signal-compatible - meaning the same schematic symbol applies, but PCB layout must use the smaller MSOP land pattern defined in Microchip's packaging drawings for 11AA160-I/MS.