FMS6400

The FMS6400 is a dual Y/C 5th order Butterworth lowpass video filter optimized for minimum overshoot and flat group delay. The FMS6400 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 2Vpp, AC or DC coupled, into either a single or dual video load. A single video load consists of a series 75 impedance matching resistor connected to a terminated 75 line. This presents a total of 150 of loading to the part. A dual load would be two of these in parallel which would present a total of 75 to the part. The gain of the Y, C and CV signals can be selected for 0dB or 6dB with 1Vpp input levels. All video channels are clamped during sync to establish the appropriate output voltage reference levels. The FMS6400 typical cutoff frequency is 7.1MHz. Option for a lower cutoff frequency of 5MHz is available. Please refer to the FMS6400-1 datasheet for further information.