CAT-5 Receiver with

Adjustable Line Equalization

AD8128

Rev. 0

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FEATURES

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

Up to 100 meters @ 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) @ 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

FUNCTIONAL BLOCK DIAGRAM

AD8128

HPF

HPF

LPF

Figure 1.

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

gain from 0 dB to 3 dB, compensating for the resistive cable

flexibility for dc-coupled systems.

Low integrated output noise and offset voltage adjust make the

AD8128 an excellent choice for dc-coupled wideband RGB-

over-CAT-5 applications. For systems where the UTP cable is

longer than 100 meters, two AD8128s 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.