GENERAL DESCRIPTION

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 VPEAKpin, 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.

FEATURES

Tuned to compensate for Category-5 (CAT-5) cable losses

Up to 100 meters at 120 MHz

2 voltage controlled frequency response adjustment pins

High frequency peaking adjustment

Broadband gain adjustment

2700 V/μs slew rate

Low output noise

1.5 mV rms integrated noise (1 GHz) at 100 meters

equalized bandwidth

DC output offset adjust

Low offset voltage error: 7 mV typ

Equalized pass-band ripple ±1 dB to 70 MHz

Input: differential or single ended

Supply current: 24 mA on ±5 V

Small 8-lead 3 mm × 3 mm LFCSP

APPLICATIONS

Keyboard-video-mouse (KVM)

RGB video over unshielded twisted pair (UTP) cable receivers

Professional video projection and distribution

Security video