? 2006 fairchild semiconductor corporation www.fairchildsemi.com fms6145 rev. 2.0.4 december 2006 fms6145 low-cost five-channel 4th-order standard de nition video filter driver fms6145 low-cost five-channel 4th-order standard de nition video filter driver features five 4th-order 8mhz (sd) lters drives single, ac- or dc-coupled, video loads (2v pp , 150 ) drives dual, ac- or dc-coupled, video loads (2v pp , 75 ) transparent input clamping ac- or dc-coupled inputs ac- or dc-coupled outputs dc-coupled outputs eliminate ac-coupling capacitors 5v only robust 8kv esd protection lead-free tssop-14 package applications cable set-top boxes satellite set-top boxes dvd players hdtv personal video recorders (pvr) video on demand (vod) description the fms6145 low-cost video filter (lcvf) is intended to replace passive lc lters and drivers with a low-cost integrated device. five 4th-order lters provide improved image quality compared to typical 2nd or 3rd-order passive solutions. the fms6145 may be directly driven by a dc-coupled dac output or an ac-coupled signal. internal diode clamps and bias circuitry may be used if ac-coupled inputs are required (see applications section for details). the outputs can drive ac- or dc-coupled single (150 ) or dual (75 ) loads. dc coupling the outputs removes the need for output coupling capacitors. the input dc levels are offset approximately +280mv at the output (see applications section for details). ordering information part number package pb-free operating temperture range packaging method FMS6145MTC14 tssop-14 yes -40c to +85c tube FMS6145MTC14x tssop-14 yes -40c to +85c tape and reel functional block diagram in1 in2 in3 in4 in5 out1 out2 out3 out4 out5 8mhz, 4 th order 6d b transparent clamp 6d b transparent clamp 6d b transparent clamp 6d b transparent clamp 6d b transparent clamp
? 2006 fairchild semiconductor corporation www.fairchildsemi.com fms6145 rev. 2.0.4 2 fms6145 low-cost five-channel 4th-order standard de nition video filter driver pin con guration fms6145 14-pin tssop in1 out1 in2 in3 out3 v cc in4 in5 nc out2 gnd out5 nc out4 1 2 3 4 5 6 7 14 13 12 11 10 9 8 pin assignments pin # name type description 1 in1 input video input, channel 1 2 in2 input video input, channel 2 3 in3 input video input, channel 3 4v cc input +5v supply, do not oat 5 in4 input video input, channel 4 6 in5 input video input, channel 5 7, 8 nc no connect 9 out5 output filtered video output, channel 5 10 out4 output filtered video output, channel 4 11 gnd output must be tied to ground, do not oat 12 out3 output filtered video output, channel 3 13 out2 output filtered video output, channel 2 14 out1 output filtered video output, channel 1
? 2006 fairchild semiconductor corporation www.fairchildsemi.com fms6145 rev. 2.0.4 3 fms6145 low-cost five-channel 4th-order standard de nition video filter driver absolute maximum ratings the ?absolute maximum ratings? are those values beyond which the safety of the device cannot be guaranteed. the device should not be operated at these limits. the parametric values de ned in the electrical characteristics tables are not guaranteed at the absolute maximum ratings. the ?recommended operating conditions? table de nes the conditions for actual device operation. functional operation under any of these conditions is not implied. performance and reliabi- lity are guaranteed only if recommended operating conditions are not exceeded. parameter min. max. unit dc supply voltage -0.3 6 v analog and digital i/o -0.3 v cc + 0.3 v output channel - any one channel (do not exceed) 50 ma reliability information symbol parameter min. typ. max. unit t j junction temperature 150 c t stsg storage temperature range -65 +150 c t l lead temperature (soldering, 10s) 300 c ja thermal resistance, jedec standard multi-layer test boards, still air 90 c/w recommended operating conditions symbol parameter min. typ. max. unit t a operating temperature range -40 +85 c v cc v cc range +4.75 +5.0 +5.25 v
? 2006 fairchild semiconductor corporation www.fairchildsemi.com fms6145 rev. 2.0.4 4 fms6145 low-cost five-channel 4th-order standard de nition video filter driver dc electrical characteristics t a = 25c, v cc = 5v, r source = 37.5 ; all inputs are ac-coupled with 0.1 f; all outputs are ac coupled with 220 f into 150 loads; unless otherwise noted. symbol parameter conditions min. typ. max. units i cc supply current (1) fms6145 (no load) 30 46 ma v in video input voltage range referenced to gnd if dc-coupled 1.4 v pp psrr power supply rejection dc (all channels) -50 db notes: 100% tested at 25c. ac electrical characteristics t a = 25c, v in = 1v pp , v cc = 5v, r source = 37.5 ; all inputs are ac coupled with 0.1 f; all outputs are ac-coupled with 220 f into 150 loads; unless otherwise noted. symbol parameter conditions min. typ. max. units av channel gain (1) all channels 5.6 6.0 6.6 db f 1db -1db bandwidth (1) all channels 4.5 6.7 mhz f c -3db bandwidth all channels 7.9 mhz f sb attenuation (stopband reject) all channels at f = 27mhz 48 db dg differential gain all channels 0.3 % d differential phase all channels 0.6 thd output distortion (all channels) v out = 1.8v pp , 1mhz 0.4 % x talk crosstalk (channel-to-channel) at 1mhz -60 db snr signal-to-noise ratio all channels, ntc-7 weighting: 100khz to 4.2mhz 75 db t pd propagation delay delay from input-to-output, 4.5mhz 59 ns notes: 100% tested at 25c. 1. 1.
? 2006 fairchild semiconductor corporation www.fairchildsemi.com fms6145 rev. 2.0.4 5 fms6145 low-cost five-channel 4th-order standard de nition video filter driver typical performance characteristics t a = 25c, v cc = 5v, r source = 37.5 ; all inputs ac coupled with 0.1 f; all outputs are ac coupled with 220 f into 150 loads; unless otherwise noted. 1 = 8.2mhz (14.78ns) 1 -50 50 -40 -30 -20 -10 0 40 delay (ns) 400khz 5 10 15 25 20 30 frequency (mhz) 30 10 20 3 2 normalized gain (db) 400khz 5 10 15 25 20 30 frequency (mhz) 5 0 -5 -10 -15 -20 -25 -30 -35 -40 -45 -50 -55 1 mkr frequency gain ref 400khz 6db 1 6.68mhz -1db bw 2 7.87mhz -3db bw 3 27mhz -48.66db -0.5 -0.4 -0.3 -0.2 0.2 differential gain (%) 1st 2nd 3rd 5th 4th 6th 0.1 -0.1 0 -60 noise (db) 400khz 1 2 3 5 46 frequency (mhz) -70 -80 -90 -100 -110 -120 -130 ntsc min = -0.31 max = 0.03 ppmax = 0.34 -0.4 -0.2 0 0.2 1.0 differential phase (deg) 1st 2nd 3rd 5th 4th 6th 0.8 0.4 0.6 ntsc min = 0.00 max = 0.63 ppmax = 0.63 figure 5. differential phase figure 3. noise vs. frequency figure 4. differential gain figure 1. frequency response figure 2. group delay vs. frequency
? 2006 fairchild semiconductor corporation www.fairchildsemi.com fms6145 rev. 2.0.4 6 fms6145 low-cost five-channel 4th-order standard de nition video filter driver typical application diagrams the following circuit may be used for direct dc-coupled drive by dacs with an output voltage range of 0v to 1.4v. ac-coupled or dc-coupled outputs may be used with ac-coupled outputs, offering slightly lower power dissipation. figure 6. typical application diagram 75 220f 220f 220f +5v fms6145 14l tssop in1 out1 in2 in3 out3 vcc in4 out4 14 13 12 11 10 9 8 1 2 3 4 5 6 7 in5 nc out2 gnd out5 nc 0.1 f 1.0 f 75 75 75 75 75 220f 75 75 75 video cables 220f 75 75 75 video cables video soc r out b out y out g out c out dac load resistors per soc specifications. ac coupling caps are optional. dvd player or stb r g b y c
? 2006 fairchild semiconductor corporation www.fairchildsemi.com fms6145 rev. 2.0.4 7 fms6145 low-cost five-channel 4th-order standard de nition video filter driver application information application circuits the fms6145 low cost video filter (lcvf) provides 6db gain from input to output. in addition, the input is slightly offset to optimize the output driver performance. the offset is held to the minimum required value to decrease the standing dc-current into the load. typical voltage levels are shown in the diagram below: there is a 280mv offset from the dc input level to the dc output level. v out = 2 * v in + 280mv. 0.0 -> 0.02v 0.3 -> 0.32v 0.65 -> 0.67v 1.0 -> 1.02v v in 0.28v 0.88v 1.58v 2.28v driven by: dc-coupled dac outputs ac-coupled and clamped y, cv, r, g, b v out 0.15v 0.5v 0.85v v in 0.58v 1.28v 1.98v driven by: ac-coupled and biased u, v, pb, pr, c v out figure 7. typical voltage levels the fms6145 provides an internal diode clamp to sup- port ac-coupled input signals. if the input signal does not go below ground, the input clamp does not operate. this allows dac outputs to directly drive the fms6145 without an ac coupling capacitor. when the input is ac coupled, the diode clamp sets the sync tip (or lowest voltage) just below ground. the worst-case sync tip compression due to the clamp cannot exceed 7mv. the input level set by the clamp, combined with the internal dc offset, keeps the output within its acceptable range. for symmetric signals like chroma, u, v, pb, and pr, the average dc bias is fairly constant and the inputs can be ac coupled with the addition of a pull-up resistor to set the dc input voltage. dac outputs can also drive these same signals without the ac coupling capacitor. a conceptual illustration of the input clamp circuit is shown in figure 8. y out video cables video cables 75 75 75 75 driver y in load1 load2 (optional) 0.65 v figure 8. input clamp circuit i/o con gurations for a dc-coupled dac drive with dc-coupled outputs, use the con guration in figure 9. dvd or stb soc dac output 75 lcvf clamp inactive 0v - 1.4v figure 9. dc-coupled inputs and outputs alternatively, if the dac?s average dc output level causes the signal to exceed the range of 0v to 1.4v, it can be ac coupled as shown in figure 10. dvd or stb soc dac output lcvf clamp active 0.1 0v - 1.4v 75 figure 10. ac-coupled inputs, dc-coupled outputs when the fms6145 is driven by an unknown external source or a scart switch with its own clamping circuitry, the inputs should be ac coupled as shown in figure 11. 75 lcvf clamp active 0.1 external video source must be ac coupled 0v - 1.4v 75 figure 11. scart with dc-coupled outputs
? 2006 fairchild semiconductor corporation www.fairchildsemi.com fms6145 rev. 2.0.4 8 fms6145 low-cost five-channel 4th-order standard de nition video filter driver the same method can be used for biased signals, with the addition of a pull-up resistor to make sure the clamp never operates. the internal pull-down resistance is 800k 20%, so the external resistance should be 7.5m to set the dc level to 500mv; as shown in figure 12. lcvf bias input 0.1 external video source must be ac coupled 500mv +/-350mv 75 7.5m 75 figure 12. biased scart with dc-coupled outputs the same circuits can be used with ac-coupled outputs if desired. dvd or stb soc dac output lcvf clamp active 0.1 0v - 1.4v 75 220 figure 13. dc-coupled inputs, ac-coupled outputs dvd or stb soc dac output 75 lcvf clamp active 0.1 0v - 1.4v 220 figure 14. ac-coupled inputs and outputs figure 15. biased scart with ac-coupled outputs note: the video tilt or line time distortion is dominated by the ac-coupling capacitor. the value may need to be incre- ased beyond 220 f to obtain satisfactory operation in some applications. power dissipation the fms6145 output drive con guration must be considered when calculating overall power dissipation. care must be taken not to exceed the maximum die junction temperature. the following example can be used to calculate the fms6146?s power dissipation and internal temperature rise. t j = t a + p d ? q ja eq. 1 where: p d = p ch1 + p ch2 + p ch3 and eq. 2 p chx = v cc ? i ch - (v o 2 /r l ) eq. 3 where: v o = 2v in + 0.280v eq. 4 i ch = (i cc /3) + (v o /r l ) eq. 5 v in = rms value of input signal i cc = 30ma v cc = 5v r l = channel load resistance board layout can also affect thermal characteristics. refer to the layout considerations section for details. the fms6145 is speci ed to operate with output currents typically less than 50ma, more than suf cient for a dual (75 ) video load. internal ampli ers are current limited to a maximum of 100ma and should withstand brief-duration short-circuit conditions; this capability is not guaranteed. lcvf clamp active 0.1 external video source must be ac coupled 0v - 1.4v 220 75 75 layout considerations general layout and supply bypassing play major roles in high-frequency performance and thermal characteristics. fairchild offers a demonstration board, fms6145demo, to guide layout and aid device testing and characterizati- on. the fms6145demo is a four-layer board with full power and ground planes. following this layout con gu- ration provides the optimum performance and thermal characteristics. for optimum results, follow the guidelines below as a basis for high-frequency layout: include 1 f and 0.1 f ceramic bypass capacitors. place the 1 f capacitor within 0.75 inches of the power pin. place the 0.1 f capacitor within 0.1 inches of the power pin. for multi-layer boards, use a large ground plane to help dissipate heat. for two-layer boards, use a ground plane that extends beyond the device by at least 0.5 inches. minimize all trace lengths to reduce series inductances.
? 2006 fairchild semiconductor corporation www.fairchildsemi.com fms6145 rev. 2.0.4 9 fms6145 low-cost five-channel 4th-order standard de nition video filter driver mechanical dimensions dimensions are in millimeters unless otherwise noted. figure 16. tssop-14 package
fms6145 low-cost five-channel 4th-order standard de nition video filter driver ? 2006 fairchild semiconductor corporation www.fairchildsemi.com fms6145 rev. 2.0.4 10
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