Adaptive Cable Equalizer

Overview:

The GS2984 supports the industry's longest cable lengths (140m) at the lowest output jitter (0.25UI). The GS2984 is a high-speed BiCMOS integrated circuit designed to equalize and restore signals received over 75Ω coaxial cable.

The device is designed to support SMPTE 424M, SMPTE292M and SMPTE 259M, and is optimized for performance at 270Mb/s, 1.485Gb/s and 2.97Gb/s. The GS2984 features DC restoration to compensate for the DC content of SMPTE pathological test patterns.

The Carrier Detect output pin (CD) indicates whether a valid input signal has been detected. It can be connected directly to the MUTE pin to mute the output on loss of carrier. A voltage programmable threshold, which can be changed via the SQ_ADJ pin, forces CD high when the input signal amplitude falls below the threshold. This allows the GS2984 to distinguish between low-amplitude SDI signals and noise at the input of the device.

The equalizing and DC restore stages are disengaged when the BYPASS pin is HIGH. No equalization occurs in Bypass mode.

The GS2984 includes a gain selection pin (GAIN_SEL) which, when tied HIGH, compensates for 6dB flat attenuation.

The differential outputs can be DC-coupled to Gennum 3.3V cable drivers and reclockers and to industry-standard 3.3V and 2.5V CML logic using the CMSET pin.

The GS2984 is footprint and drop-in compatible with existing GS2974 designs, with no additional application changes required.

The device is available in a 16-pin, 4mm x 4mm QFN package.

Power consumption of the GS2984 is typically 195mW.

The GS2984 is Pb-free, and the encapsulation compound does not contain halogenated flame retardant.

This component and all homogeneous subcomponents are RoHS compliant.