The M21443 is a twelve channel device designed to enable the transmission of multi-gigabit serial data through the most challenging environments. The device features twelve independent, programmable equalizers that equalize data at rates up to 4.25 Gbps. The M21443 is ideal for redundancy switch applications for buses that are developed in groups of four such as XAUI and PCI Express. Hardware switch control allows for very fast switching during failover conditions. The M21443 can also be controlled via an I2C compatible bus or self-configure from an external EEPROM without the need for a host processor. For compatibility with 2.5 Gbps PCI-Express and 3.0 Gbps S-ATA/SAS systems, the M21443 is designed with an electrical idle pass-through function to drive the differential output to the common mode level during OOB signaling. The device is available in a 14x14 mm, 100-pin eTQFP package.