Microchip Technology 11LC161-I/TO

Overview

11LC161-I/TO from Microchip Technology Inc. is a 16 Kbit (2,048 × 8) serial EEPROM with UNI/O® single I/O bus interface, operating from 2.5V to 5.5V over -40°C to +85°C. It features 16-byte page-write buffer, STATUS register with WIP/WEL bits, and block write protection for 0%, 25%, 50%, or 100% of memory. Used in embedded system configuration storage where minimal pin count and low standby current are critical.

For engineers reviewing the 11LC161-I/TO datasheet, 11LC161-I/TO pinout, 11LC161-I/TO application, or 11LC161-I/TO equivalent, key selection considerations include its TO-92 package compatibility, 100 kbps UNI/O® bit rate, 1 µA max standby current (I-temp), 1,000,000 erase/write endurance, and device address 0xA1 for multi-device bus operation.

Technical Context

The 11LC161-I/TO implements Manchester-encoded UNI/O® protocol on a single SCIO line, eliminating separate clock and data lines. Its internal re-synchronization circuitry tolerates ±0.50% frequency drift per byte and ±0.06 UI edge jitter, enabling robust communication with microcontroller GPIOs.

It integrates Schmitt-trigger inputs for noise immunity, output slope control to suppress ground bounce, and a current-limited SCIO driver (±3 mA at 2.5V). The STATUS register provides real-time WIP and WEL status, while block protection bits (BP1/BP0) enable hardware-level write locking without software overhead.

Key Specifications

Pinout & Package

11LC161-I/TO is housed in a 3-lead TO-92 package (top-down view: Pin 1 = VCC, Pin 2 = VSS, Pin 3 = SCIO). 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 11AA161-I/TO, the 11LC161-I/TO trades 1.8V operation for improved noise margin at 2.5V+, while 24LC16B-I/P requires additional pins and layout changes - making 11LC161-I/TO optimal for new designs prioritizing pin efficiency and TO-92 compatibility.

Availability

11LC161-I/TO 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 temperature ranges.

Supply support for 11LC161-I/TO 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 for embedded applications.

The 11LC161-I/TO belongs to Microchip's UNI/O® serial EEPROM family, designed specifically for space-constrained, low-pin-count systems needing reliable nonvolatile storage without dedicated serial interfaces.

FAQ

What is the device address of the 11LC161-I/TO and how does it differ from other 11LCXXX parts?

The 11LC161-I/TO uses hardwired device address 0xA1, distinguishing it from 0xA0-addressed variants like 11LC160-I/TO. This allows both part numbers to coexist on the same UNI/O® bus without address conflict, enabling flexible memory expansion in multi-device systems while maintaining identical electrical and timing behavior.

Does the 11LC161-I/TO support write operations without external timing components?

Yes, the 11LC161-I/TO performs self-timed write cycles including auto-erase, requiring no external capacitors or clocks. Internal timing is managed by on-chip circuitry, with typical write cycle time of 5 ms for byte writes and up to 10 ms for page writes - fully transparent to the host MCU.

Can the 11LC161-I/TO be used in automotive applications requiring extended temperature range?

No - the "I" suffix in 11LC161-I/TO denotes Industrial temperature grade (-40°C to +85°C). For automotive applications, Microchip offers the 11LC161-E/TO variant rated to -40°C to +125°C; the "I" version is not qualified for under-hood or other high-temperature automotive use cases.

How does the STATUS register in the 11LC161-I/TO improve system reliability during writes?

The STATUS register in the 11LC161-I/TO provides real-time WIP (Write-In-Progress) and WEL (Write-Enable Latch) bits. Host firmware can poll the WIP bit to avoid premature read attempts, and verify WEL before issuing write commands - preventing silent failures due to latch reset after power cycles or WRDI execution.

What package options are available for the 11LC161-I/TO besides TO-92?

The 11LC161-I/TO is specifically qualified in the 3-lead TO-92 package. Other 11LC161 variants are offered in SOT-23 (TT), PDIP (P), SOIC (SN), MSOP (MS), and TDFN (MN), but the "/TO" suffix confirms TO-92 packaging - no alternate packages are assigned to this exact orderable part number.