1-kb Dual Mode Serial EEPROM for VESA™ "Plug-and-Play"

The CAT24C21 is a 1-kb Serial CMOS EEPROM internally organized as 128 words of 8 bits each. The device complies with the Video Electronics Standard Association's (VESA™), Display Data Channel (DDC™) standards for "Plug-and-Play" monitors. The "transmit-only" mode (DDC1™) is controlled by the VCLK clock input and the "bi-directional" mode (DDC2™) is controlled by the SCL clock input, with both modes sharing a common SDA input/output (I/O). The transmit-only mode is a read-only mode, while the bi-directional mode is a read and write mode following the I²C protocol. In write mode the CAT24C21 features a 16-byte page write buffer. The device is available in 8-in DIP, SOIC, TSSOP, MSOP and TDFN packages.