The AD8128 is a high speed, differential receiver/equalizer that
compensates for the transmission losses of unshielded twisted pair
(UTP) CAT-5 cables. Various frequency dependent gain stages
are summed together to best approximate the inverse frequency
response of CAT-5/CAT-5e cable. An equalized bandwidth of
120 MHz can be achieved for 100 meters of cable.
The AD8128 can be used as a standalone receiver/equalizer or
in conjunction with the AD8143, triple differential receiver, to
provide a complete low cost solution for receiving RGB over
UTP cable in such applications as KVM.
The AD8128 has three control pins for optimal CAT-5/CAT-5e
compensation. The equalized cable length is directly proportional
to the voltage applied to the VPEAK pin, which controls the amount
of high frequency peaking. VGAIN adjusts the broadband gain
from 0 dB to 3 dB, compensating for the resistive cable loss.
VOFFSET allows the output to be shifted by ±2.5 V, adding
flexibility for dc-coupled systems.
Low integrated output noise and offset voltage adjust make the
AD8128 an excellent choice for dc-coupled wideband RGB-overCAT-5
applications. For systems where the UTP cable is longer
than 100 meters, two AD8128 devices can be cascaded to
compensate for up to 200 meters of CAT-5/CAT-5e.
The AD8128 is available in a 3 mm × 3 mm 8-lead LFCSP and
is rated to operate over the extended temperature range of
−40°C to +85°C.
Applications
- Keyboard-video-mouse (KVM)
- RGB video over unshielded twisted pair (UTP) cable receivers
- Professional video projection and distribution
- Security video
