●The FMS6410B is a dual Y/C fifth-order Butterworth low-pass video filter optimized for minimum overshoot and flat group delay. The device also contains a summing circuit to generate filtered composite video. In a typical application, the Y and C input signals from DACs are AC coupled into the filters. Both channels have DC restore circuitry to clamp the DC input levels during video sync. The Y and C channels use separate feedback clamps. The clamp pulse is derived from the Y channel. All outputs are capable of driving 2 V, AC or DC coupled, into either a single or dual video load. A single video load consists of a series 75 Ω impedance matching resistor connected to a terminated 75 Ω line. This presents a total of 150 Ω of loading to the part. A dual load is two of these in parallel, which presents a total of 75 Ω to the part. The gain of the Y, C, and CV signals is 6dB with 1 V input levels. All video channels are clamped during sync to establish the appropriate output voltage reference levels.
●Features
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● 7.1 MHz fifth-order Y, C filters with composite summer
● 50dB stopband attenuation at 27 MHz on Y, C, and CV outputs
● Better than 0.1dB flatness to 4.5 MHz on Y,C, and CV outputs
● No external frequency selection components or clocks
● <5ns group delay deviation on Y, C, and CV outputs
● AC-coupled inputs
● AC-or DC-coupled outputs
● Capable of PAL frequency selection components or clocks
● 0.3% differential gain with 0.2° differential phase on Y,C, and CV channels
● Integrated DC restore circuitry with low tilt
