Microchip Technology 11AA020T-I/CS16K

Overview

11AA020T-I/CS16K from Microchip Technology Inc. is a 2 Kbit (256 × 8) serial EEPROM using the UNI/O® single I/O bus interface. It operates from 1.8V to 5.5V, draws ≤1 µA standby current (I-temp), supports 100 kbps bit rate, and features 16-byte page-write buffering with built-in block write protection for industrial temperature applications (–40°C to +85°C) in Chip Scale Package.

For engineers reviewing the 11AA020T-I/CS16K datasheet, 11AA020T-I/CS16K pinout, 11AA020T-I/CS16K application, or 11AA020T-I/CS16K equivalent, key selection criteria include low-voltage operation down to 1.8V, Schmitt-trigger SCIO input for noise immunity, Manchester-encoded timing tolerance (±0.5% frequency drift per byte), self-timed write cycle (≤10 ms), and compatibility with microcontroller GPIO-based UNI/O® masters.

Technical Context

The 11AA020T-I/CS16K implements a Manchester-encoded, single-wire UNI/O® protocol where clock and data share the SCIO line; timing synchronization occurs via start-header detection and dynamic re-synchronization on every MAK bit. Its internal architecture includes a 16-byte page latch, STATUS register with WIP/WEL/BP bits, and current-limited slope-controlled output driver.

It supports four block-protection modes (none, 1/4, 1/2, or full array), uses an 8-bit instruction set (e.g., 0x03 READ, 0x6C WRITE, 0x96 WREN), and enforces write enable latch control with automatic reset after successful write, erase, or status register update - all while maintaining <50 µA idle current and >200-year data retention.

Key Specifications

Pinout & Package

11AA020T-I/CS16K is housed in a 4-lead Chip Scale Package (CSP), with footprint optimized for space-constrained PCBs. Pin 1 = VCC, Pin 2 = VSS, Pin 3 = NC (no connect), Pin 4 = SCIO (serial clock/data I/O).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 11AA020T-I/SN, the 11AA020T-I/CS16K saves board space and suits high-density layouts, while versus AT24C02C-SSHM-T, it reduces GPIO usage and improves noise resilience - making it optimal for next-gen compact, low-pin-count embedded systems.

Availability

11AA020T-I/CS16K is available at Aetrix Electronics and suitable for industrial sensor nodes, medical wearables, and automotive body electronics requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for 11AA020T-I/CS16K 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 solutions, with emphasis on embedded control and reliability-critical applications.

The 11AA020T-I/CS16K belongs to Microchip's UNI/O® serial EEPROM family, designed specifically for space- and pin-constrained systems needing robust, low-power nonvolatile storage with minimal MCU resource overhead.

FAQ

What is the UNI/O® interface used by the 11AA020T-I/CS16K, and how does it differ from I²C or SPI?

The 11AA020T-I/CS16K uses Microchip's patented UNI/O® bus - a single-wire, Manchester-encoded serial interface that combines clock and data on the SCIO pin. Unlike I²C (2-wire, open-drain) or SPI (4-wire, separate clock/MOSI/MISO/SS), UNI/O® requires only one GPIO and no external pull-ups or level shifters. This reduces pin count, PCB routing complexity, and EMI susceptibility while maintaining deterministic timing through master-controlled bit periods and slave re-synchronization on each MAK bit.

Does the 11AA020T-I/CS16K support write protection, and how is it configured?

Yes, the 11AA020T-I/CS16K supports hardware-configurable block write protection via BP0 and BP1 bits in its STATUS register. These bits are programmed using the WRSR (Write Status Register) command and determine whether 0%, 25%, 50%, or 100% of the memory array is write-protected. Protection is nonvolatile and persists across power cycles. Additionally, built-in power-on/off write protection circuitry prevents inadvertent writes during voltage ramp-up or brownout conditions - ensuring data integrity without software intervention.

What is the maximum write speed and page size of the 11AA020T-I/CS16K?

The 11AA020T-I/CS16K supports a maximum serial bus frequency of 100 kHz, enabling up to 100 kbps effective throughput. Its page-write buffer holds up to 16 bytes, allowing burst writes within a single physical page (addresses aligned to 16-byte boundaries). A full 16-byte page write completes in ≤10 ms, while individual byte writes also require ≤10 ms due to self-timed internal erase-before-write. Write operations must be preceded by WREN and terminated with NoMAK to initiate the cycle.

Can the 11AA020T-I/CS16K operate reliably at 1.8V, and what are its current consumption figures?

Yes, the 11AA020T-I/CS16K is fully specified for 1.8V operation across the industrial temperature range (–40°C to +85°C). At 1.8V, it draws ≤1 mA active current during read/write and ≤1 µA standby current (max). Its low-voltage capability eliminates the need for voltage translators when interfacing with 1.8V MCUs or ASICs, and its sub-µA standby current makes it suitable for battery-powered applications requiring multi-year operational life without maintenance.

How is the SCIO pin electrically characterized on the 11AA020T-I/CS16K, and what design considerations apply?

The SCIO pin on the 11AA020T-I/CS16K is a bidirectional, current-limited, slope-controlled I/O with Schmitt-trigger input. It features hysteresis ≥0.05×VCC, rise/fall times ≤100 ns, and output drive limited to ±3 mA at 2.5V and ±4 mA at 5.5V. Designers must use a weak external pull-up (typically 10–100 kΩ) and avoid capacitive loading >100 pF to meet timing specifications. The slope control inherently suppresses ground bounce, and the Schmitt trigger rejects noise spikes <50 ns - eliminating need for external filtering in most industrial environments.