24LC128-E/ST

Memory IC Overview

The Microchip Technology 24LC128-E/ST is a 16K x 8 (128 Kbit) Serial Electrically Erasable PROM (EEPROM). It operates with a single supply voltage ranging from 2.5V to 5.5V and features an I2C compatible two-wire serial interface supporting up to 400 kHz clock frequency. The device utilizes low-power CMOS technology, offering a maximum write current of 3 mA and standby current of 5 µA at extended temperatures. It includes a 64-byte page write buffer, hardware write-protect capability via the WP pin, and Schmitt trigger inputs for noise suppression. The component is housed in an 8-lead TSSOP package and supports operation across an extended temperature range of -40°C to +125°C.

Memory IC Feature Summary

• Supports cascading up to eight devices on the same bus using configurable chip select inputs A0, A1, and A2.
• Features hardware write protection that inhibits write operations when the WP pin is tied to VCC.
• Includes output slope control to eliminate ground bounce and Schmitt trigger inputs for improved noise spike suppression.

Memory IC Applications

• Personal communications systems requiring non-volatile data storage
• Data acquisition applications needing reliable parameter retention
• Embedded systems utilizing I2C bus architecture

Memory IC Procurement Notes

Verify the specific ordering suffix matches the required temperature grade and package type. Confirm the voltage range aligns with system requirements, as the 'E' suffix denotes extended temperature operation starting at 2.5V. Ensure compatibility with existing I2C bus pull-up resistor values for the target clock speed.

Memory IC Selection Notes

Select this part for applications requiring extended industrial temperature performance (-40°C to +125°C). Choose the TSSOP package for surface-mount assembly needs. Consider the 64-byte page write buffer for efficient bulk data writing. Verify that the 2.5V minimum operating voltage suits the system power supply rails.

Memory IC Part Context

This component belongs to the 24XX128 family, which also includes the 24AA128 and 24FC128 variants. The 24LC128 specifically targets applications requiring operation down to 2.5V, distinguishing it from the 1.7V capable 24AA128 and the higher-speed 24FC128. All variants share identical pinouts and functional interfaces.

Memory IC Replacement Considerations

Direct substitutes within the same family include 24LC128-I/ST for industrial temperature range or 24LC128T-E/ST for tape-and-reel packaging. Cross-vendor equivalents may exist but require verification of I2C timing parameters and voltage specifications.

Memory IC FAQ

How does the WP pin function?

The Write-Protect (WP) pin allows hardware control over write operations. When tied to VCC, write operations are inhibited while read operations remain unaffected. When tied to VSS, write protection is disabled.

What is the maximum number of devices on one bus?

Up to eight 24LC128 devices can be connected to the same I2C bus by configuring the A0, A1, and A2 chip select pins to different logic levels.