Gs2994 Adaptive Cable Equalizer
The GS2994 is a high-speed BiCMOS integrated circuit designed to equalize and restore signals received over 75? 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 GS2994 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 SLEEP pin to enable automatic power-down upon 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 GS2994 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 GS2994 includes a gain selection pin (GAIN_SEL) which, when tied HIGH, compensates for 6dB flat attenuation.