LM1208 130 MHz/85 MHz RGB Video Amplifier System with Blanking General Description The LM1208 is a very high frequency video amplifier system intended for use in high resolution RGB monitor applications. In addition to the three matched video amplifiers, the LM1208 contains three gated single ended input black level clamp comparators for brightness control, three matched DC controlled attenuators for contrast control, and three DC controlled sub-contrast attenuators providing independent full range gain control in each channel for wide range white balance. All DC control inputs offer high input impedance and an operation range from 0V to 4V for easy interface to bus controlled alignment systems. The LM1208 also contains a blanking circuit which clamps the video output voltage during blanking to within 0.1V above ground. This feature provides blanking capability at the cathodes of the CRT. A spot killer is provided for CRT phosphor protection during power-down. Features n Three wideband video amplifiers 130 MHz (LM1208) @ −3 dB (4 VPP output) n Matched (±0.1 dB or 1.2%) attenuators for contrast control n ESD susceptibility above 3 kV n Three externally gated single ended input comparators for cutoff and brightness control n 0V to 4V, high input impedance DC contrast control (>40 dB range) n 0V to 4V, high input impedance DC full range gain control (Drive) for each video channel (> 40 dB range) n Spot killer, blanks output when VCC < 10.6V n Capable of 7 VPP output swing (slight reduction in bandwidth) n Output stage blanking n Output stage directly drives most hybrid or discrete CRT drivers Applications n High resolution RGB CRT monitors n Video AGC amplifiers n Wideband amplifiers with gain and DC offset controls n Interface amplifiers for LCD or CCD systems