Microchip Technology 24AA256T-I/CS16K

Overview

24AA256T-I/CS16K from Microchip Technology Inc. is a 256-Kbit (32K × 8) I²C-compatible serial EEPROM with 1.7V–5.5V single-supply operation, 400 kHz maximum clock frequency, and industrial temperature range (–40°C to +85°C). It features 64-byte page write buffer, hardware write-protection via WP pin, and Schmitt-trigger inputs for noise immunity-used in embedded system configuration storage, sensor calibration data retention, and firmware parameter backup.

For engineers reviewing the 24AA256T-I/CS16K datasheet, 24AA256T-I/CS16K pinout, 24AA256T-I/CS16K application, or 24AA256T-I/CS16K equivalent, key selection criteria include low-voltage operation down to 1.7V, I²C bus compatibility up to 400 kHz, 1 µA standby current, and 8-pin SOIC package with A0/A1/A2 address pins enabling multi-device bus topology.

Technical Context

The 24AA256T-I/CS16K implements a two-wire I²C interface with open-drain SDA/SCL requiring external pull-ups, supports cascaded addressing via three hardware-configurable chip-select inputs (A0–A2), and uses internal high-voltage generation for EEPROM programming. Its architecture includes a 64-byte page latch, auto-incrementing address pointer, and self-timed erase/write cycle with no external timing components required.

It operates across 1.7V–5.5V with full functionality at minimum VCC, delivers 3 mA max write current and 1 µA max standby current (I-temp), and incorporates slope-controlled outputs to suppress ground bounce. The device enforces strict I²C timing compliance-including THD:STA ≥ 600 ns and TAA ≤ 900 ns at VCC ≥ 2.5V-and integrates Schmitt-trigger inputs with 0.05×VCC hysteresis for robust noise rejection.

Key Specifications

Pinout & Package

24AA256T-I/CS16K is supplied in an 8-lead SOIC (Small Outline Integrated Circuit) package with gull-wing leads, 1.27 mm pitch, and JEDEC MS-012AC footprint. Pin 1 is marked by a beveled corner or dot; pin numbering follows standard SOIC convention (counterclockwise from pin 1).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC256-I/P and AT24C256-10PU-2.7, the 24AA256T-I/CS16K uniquely supports 1.7V operation and 1M-cycle endurance in an industry-standard SOIC package-making it optimal for battery-backed, high-reliability industrial designs requiring extended voltage margin and long-term data integrity.

Availability

24AA256T-I/CS16K is available at Aetrix Electronics and suitable for industrial sensor calibration storage, smart meter configuration backup, and embedded system bootloader settings requiring stable component supply across extended product lifecycles.

Supply support for 24AA256T-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 leading provider of microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA256T-I/CS16K belongs to Microchip's 24XX256 family of I²C serial EEPROMs, engineered for ultra-low-power, wide-voltage-range nonvolatile data storage in space-constrained industrial and automotive subsystems.

FAQ

What is the minimum operating voltage for the 24AA256T-I/CS16K?

The 24AA256T-I/CS16K operates down to 1.7V across its full industrial temperature range (–40°C to +85°C), enabling direct integration with 1.8V logic families and battery-powered systems without voltage translation. This specification is validated per DS20001203Y-page 3, Table 1-1, and distinguishes it from the 24LC256 variant which requires ≥2.5V.

How many devices can share the same I²C bus with the 24AA256T-I/CS16K?

Up to eight 24AA256T-I/CS16K devices can be connected to a single I²C bus using unique combinations of A0, A1, and A2 pin states (0 or 1), yielding I²C addresses 0x50 through 0x57. Each device must have distinct A0–A2 wiring; floating these pins is not permitted per datasheet Section 2.1.

Does the 24AA256T-I/CS16K support page write operations, and what is the buffer size?

Yes, the 24AA256T-I/CS16K supports page write operations with a 64-byte on-chip buffer. Writes must remain within a single 64-byte physical page boundary (e.g., 0x0000–0x003F); crossing boundaries causes wraparound. Page write completes in ≤5 ms and reduces I²C transaction overhead significantly versus byte writes.

What is the function of the WP pin on the 24AA256T-I/CS16K?

The WP (Write-Protect) pin on the 24AA256T-I/CS16K is a hardware-level enable/disable control for all write operations. When tied to VCC, writes to the entire 256-Kbit array are inhibited while read operations remain fully functional. WP state is sampled at the Stop condition of each write command per datasheet Figure 1-1 and Section 6.3.

Is the 24AA256T-I/CS16K RoHS compliant and qualified for automotive use?

The 24AA256T-I/CS16K is RoHS compliant per datasheet Feature list, but it is not AEC-Q100 qualified. Only the 24AA256 automotive-grade variants (e.g., 24AA256-E/MNY) carry AEC-Q100 qualification. The "I" suffix in 24AA256T-I/CS16K denotes Industrial temperature grade (–40°C to +85°C), not automotive qualification.