24LC128T-I/SM

Memory IC Overview

The Microchip Technology 24LC128T-I/SM is a 16K x 8 (128 Kbit) Serial Electrically Erasable PROM (EEPROM). It operates on a single supply voltage ranging from 2.5V to 5.5V and features a Two-Wire Serial Interface compatible with I2C protocols, supporting maximum clock frequencies of 400 kHz. The device utilizes low-power CMOS technology, ensuring a maximum write current of 3 mA and a standby current of 1 µA in industrial temperature ranges (-40°C to +85°C). Key functional specifications include a page write time of 5 ms maximum, a 64-byte page write buffer, hardware write-protect capabilities via the WP pin, and Schmitt trigger inputs for noise suppression.

Memory IC Feature Summary

• Supports cascading up to eight devices on the same bus using configurable chip address inputs A0, A1, and A2.
• Includes a 64-byte page write buffer to facilitate efficient sequential data writing operations.
• Features hardware write protection controlled by the WP pin to inhibit array writes when tied to VCC.
• Incorporates Schmitt trigger inputs and output slope control to suppress noise and eliminate ground bounce.

Memory IC Applications

• Personal communications systems requiring non-volatile data storage
• Data acquisition applications needing reliable parameter retention
• Industrial control systems utilizing I2C serial interfaces

Memory IC Procurement Notes

Verify that the ordering suffix 'I' corresponds to the Industrial temperature range (-40°C to +85°C) and 'SM' indicates the 8-Lead MSOP package. Confirm the specific datasheet revision matches your design requirements, as electrical characteristics may vary between revisions. Ensure compatibility with your system's I2C voltage levels and pull-up resistor configurations before finalizing procurement.

Memory IC Selection Notes

Select this component when a 128 Kbit EEPROM with I2C interface is required within the 2.5V to 5.5V operating voltage range. Consider the 64-byte page write capability for applications involving frequent small data updates. Verify that the MSOP package dimensions fit your PCB layout constraints and that the industrial temperature rating meets your environmental operating conditions.

Memory IC Part Context

This part belongs to the 24XX128 family, which includes the 24AA128 and 24FC128 variants. While functionally similar, the 24LC128 is distinguished by its minimum operating voltage of 2.5V, whereas the 24AA128 and 24FC128 support operation down to 1.7V. The 24FC128 also supports higher clock frequencies up to 1 MHz compared to the 400 kHz limit of the 24LC128.

Memory IC Replacement Considerations

Direct substitutes within the same family include the 24LC128-I/SN (SOIC package), 24LC128-I/ST (TSSOP package), and 24LC128-I/MF (DFN package). For lower voltage applications, the 24AA128 or 24FC128 series may be considered, provided the voltage and speed requirements are met.

Memory IC FAQ

How many devices can be connected to the same I2C bus?

Up to eight 24LC128 devices can be connected to the same bus by configuring the A0, A1, and A2 chip select pins to different logic levels.

What is the purpose of the WP pin?

The Write-Protect (WP) pin allows hardware control over write operations. When tied to VCC, it inhibits all write cycles to the array; when tied to VSS, write operations are enabled.

Does the device support acknowledge polling?

Yes, the device does not generate an Acknowledge signal during an internal write cycle, allowing the master to poll the bus to determine when the write operation is complete.