Video conditioners

Maxim has introduced the MAX7450/MAX7451/MAX7452 family of complete front-end, standard-definition video signal conditioners.

Each device restores the DC level of the AC-coupled video input, corrects for amplitude variations up to ±6 dB, detects fault conditions, and filters out-of-band noise.

The devices optimise the video input-signal quality for further video processing through a crosspoint switch or a video decoder. They compensate for cable loss or initial amplitude variations from various video sources. The devices are suitable for security and other video-switching applications where the camera input connects to the video switch matrix.

This family of video signal conditioners operates from ±5 V (7450), ±3 V (7451), and +5 V (7452). The 7450/7451 set the output blanking level of the video signal to GND using a back-porch clamp approach. The 7452 features a user-adjustable back-porch clamp level ranging from 1 to 1.5 V.

Each device integrates an input video clamp, automatic gain control, loss-of-sync detector and an out-of-band lowpass filter. An external pin adjusts the output buffer gain between +6 or 0 dB range to drive either a 150 ohm video load with a full 2 V peak-to-peak video signal or a 1 V peak-to-peak video signal. These devices also feature an AGC disable function.