FMS6406 is a highly integrated standard-definition, low-pass reconstruction video filter/driver from Fairchild Semiconductor. This device features an integrated sound notch and output drivers that meet the latest cable and satellite set-top box performance requirements of 170 ns group delay predistortion. The FMS6406 compensates for the inherent distortion in the TV receiver by including a group delay and chroma-luma delay FCC predistortion circuit that prevents the image's high-frequency edges from appearing distorted on the TV screen. The notch filter creates a window in the video signal at approximately 4.5 MHz to eliminate interference between the audio and video before these signals are combined in the channel 3/4 RF modulator.

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According to Fairchild, it reduces board space by 30% to 40% by effectively replacing discrete reconstruction filters, an external sound notch and group delay compensation circuits and cable drivers, while increasing system reliability in set-top box and personal video recorder (PVR) applications.

The FMS6406, a fifth-order 7.6 MHz low-pass video filter, eliminates unwanted digital artifacts by significantly reducing the clock and image frequencies after the digital-to-analog conversion process occurs on an MPEG chip. This video filter/driver is also capable of dc coupling on the outputs to improve the low-frequency video, while at the same time eliminating the need for three large capacitors. Typical designs for set-top boxes offer both S-video and composite-video outputs. FMS6406 offers separate chrominance and luminance outputs to directly drive the S-video output. These outputs are also internally summed to form a composite video signal. The composite- and S-video outputs provide a fixed gain of 6 dB and offer the flexibility of either ac or dc coupling.

Other features include a Y sync tip clamp and chroma blanking clamp, filtered outputs that are Y/C and CV with 50 dB stopband attenuation at 27 MHz and better than 0.5 dB flatness to 4.2 MHz, and all outputs are capable of driving 2 Vpp, ac- or dc-coupled, into either a single or dual 75-Ohm video load. Plus it offers an internal chroma-luma summing circuit for driving composite video outputs.

The FMS6406 is offered in a space-saving 8-pin SOIC package. This product is lead (Pb)-free and meets or exceeds the requirements of the joint IPC/JEDEC standard J-STD-020B and is compliant with European Union requirements. Pricing (1000 pieces) for both FMS6406CS (rail) and FMS6406CSX (tape reel) is $1.69