24LC21AT-I/SN

Memory IC Overview

The Microchip Technology 24LC21AT-I/SN is a 1Kb (128 x 8-bit) dual-mode serial EEPROM housed in an 8-pin SOIC package. It operates on a single supply voltage ranging from 2.5V to 5.5V and supports I²C bus communication with clock frequencies up to 400 kHz. The device features a page write buffer for eight bytes, self-timed write cycles of 10 ms, and access times as fast as 900 ns. Designed for industrial applications, it functions within a temperature range of -40°C to +85°C.

Memory IC Feature Summary

• Dual-mode operation supporting both Transmit-Only mode for monitor identification and Bidirectional mode for standard I²C read/write access.
• Hardware write protection capability enabled by holding the VCLK pin low during bidirectional operations.
• Low-power CMOS technology ensuring minimal active and standby current consumption across the operating voltage range.

Memory IC Applications

• Monitor identification compliant with DDC1/DDC2 interface specifications
• Storage of configuration and control information in industrial systems
• Serial transmission of data in display equipment

Memory IC Procurement Notes

Verify that the 'T' suffix indicates tape-and-reel packaging rather than tube packaging. Confirm the 'I' designation matches the required -40°C to +85°C industrial temperature range. Ensure the SOIC package width aligns with PCB layout constraints. Cross-reference the specific datasheet revision to confirm electrical characteristics remain consistent with design requirements.

Memory IC Selection Notes

Select this component when a dual-mode interface is necessary for transitioning between EDID transmission and standard I²C control. The 1Kb capacity suits small configuration storage needs. Verify that the system can provide the required VCLK signal for write enable or transmit clocking. Consider the 8-byte page buffer limit when designing write algorithms to prevent data overwrites at page boundaries.

Memory IC Part Context

This part belongs to the 24LC21A family of 1Kb serial EEPROMs manufactured by Microchip Technology. It serves as a non-volatile memory solution designed specifically for applications requiring compatibility with Display Data Channel standards while maintaining standard I²C functionality for general data storage tasks.

Memory IC Replacement Considerations

The 24LC21A is the base model for this series. Other variants within the same family may offer different packaging options such as PDIP or alternative temperature grades like commercial range devices.