The DS25BR400 is a quad 250 Mbps 2.5 Gbps CML transceiver, or 8-channel buffer, for use in backplane and cable applications. With operation down to 250 Mbps, the DS25BR400 can be used in applications requiring both low and high frequency data rates. Each input stage has a fixed equalizer to reduce ISI distortion from board traces. The equalizers are enabled through two control pins. These control pins provide flexibility in applications where ISI distortion may vary from one direction to another. All output drivers have four selectable steps of de-emphasis to compensate for transmission loss. The de-emphasis blocks are also grouped in fours. In addition, the DS25BR400 also has loopback control capability on four channels. All the CML drivers have 50 termination to Vcc. All receivers are internally terminated with differential 100.