LD6143 three channel 4th order video filter driver for pricing, delivery, and ordering information, please contact swid at +86-023-62836174, or visit swid ?s website at www.swid.com.cn 1 description the l d 61 43 video filter dri v er is inten d e d to repla c e pa ssi v e lc filters and drive r s with a integrate e e f vice. three fourth -orde r filters provide imp r o v ed image qu ality compare d to typical 2nd or 3rd order passive solutions. the l d 61 43 may be drive n by a dc o r an ac-cou pled video sig nal. the output s can drive ac o r dc-coupl ed singl e
150 ? or dual
75 ? loads. feature three fourth-order 8mhz standard definition
sd video filters transparent input clamping dual video load drive
2vpp, 75 ? ac or dc-coupled inputs ac or dc-coupled outputs 5v only soic-8 package application use for the cabl e set top boxes, satel lite set t op b o xes, dv d pl ayers, hdtv, perso nal vid eo recorders
pvr or video on demand
vod . functional block diagram pin configuration 1 2 3 4 5 6 7 8 in 1 in 2 in 3 vc c ou t1 ou t2 ou t3 gn d pin description pin pin description 1 in1 video input, channel 1 2 in2 video input, channel 2 3 in3 video input, channel 3 4 v cc +5v supply, do not float 5 gnd ground, do not float 6 out3 filtered output, channel 3 7 out2 filtered output, channel 2 8 out1 filtered output, channel 1 www..net
LD6143 three channel 4th order video filter driver swid integrated products, 5.f , bu ilding b, inf o rmation & t e c hnology park, e c onomic & t e c hnological developmen t zon e , ch on g qin g , ch in a. tel: (86 23)62836174 fax: (86 23)62836149 2 absolute maximum rating parameter sy mbol min. max. unit supply voltage v cc 'c 0.3 6 v analog and digital input / output i/o 'c 0 . 3 v cc 0.3 v output current
any one channel i o - - 5 0 m a storage temperature t s 'c 55 150 junction temperature t j - - 1 5 0 lead temperature
soldering, 10s - - 3 0 0 recommended operating condition parameter sy mbol min. ty p. max. unit supply voltage range v cc 4 . 7 5 5 . 0 5 . 2 5 v video input voltage range
referenc ed to gnd if dc-c oupled v in - - 1 . 4 - - v pp operating temperature range t a 0 2 5 7 0 electrical characteristic v cc = 5.0v, v in = 1vpp, rsource = 3 7 .5 ? , all inp u ts ac cou p l ed with 0.1 f, all outputs ac coupled with 220f into 150 ? load, t a = 0 j 70 ; unless otherwise noted p a r a m e t e r s y m b o l c o n d i t i o n s min. ty p . m a x . unit supply current i cc no input signal, no load -- -- 27 ma pow e r supply rejection ratio psrr dc, all channels -- -- 40 db channel gain av all channels 5.5 6.0 6.6 db -1db bandw idth f 1db all c h a n n e l s 4 . 5 7 . 0 9 . 0 mhz -3db bandw idth f c all channels 5.5 8.0 10.0 mhz stopband attenuation f sb all channels, f = 27mhz 35 40 -- db differential gain dg all channels -- -- 1.0 % differential phase d a l l c h a n n e l s - - - - 1 . 0 output distortion t hd all ch an nels, v out =1 .8 v pp , 1mhz -- 0.4 0.9 % c r o s s t a l k x ta l k channel-to-channel , at 1mhz -- -- 50 db signal-to-noise ratio s nr all channels, nt c-7 w e ighting: 100khz to 4.2mhz 5 5 - - - - d b propagation delay t pd input-to-output, 4.5mhz - - - - 1 0 0 n s e-mail: market@ s wid.com.cn www..net
LD6143 three channel 4th order video filter driver swid integrated products, 5.f , bu ilding b, inf o rmation & t e c hnology park, e c onomic & t e c hnological developmen t zon e , ch on g qin g , ch in a. tel: (86 23)62836174 fax: (86 23)62836149 3 typical performance characteristic v cc = 5.0v, v in = 1vpp, rsource = 3 7 .5 ? , all inputs ac cou p led with 0.1f, all o u t p u t s a c coupled with 220f into 150 ? load, t a =25 ; unless otherwise noted frequency response noise v s . frequency e-mail: market@ s wid.com.cn www..net
LD6143 three channel 4th order video filter driver swid integrated products, 5.f , bu ilding b, inf o rmation & t e c hnology park, e c onomic & t e c hnological developmen t zon e , ch on g qin g , ch in a. tel: (86 23)62836174 fax: (86 23)62836149 4 application information application circuit the ld6 143 video filter provide s 6db gain from inp u t to output. in addition, the input will be slightly offset to optimize the output driver performa n ce. the offset is held to the minimum requi re d value to decrea s e the standin g dc current into the load. typical voltage levels a r e shown in the figure 1. there will be a 280mv offset from the dc input level to the dc output level. v out =2v in + 280mv figure 1. ty pical v o ltage lev e l the l d 61 43 provide s a n internal diode clamp to sup port ac cou p l ed input sign als. if the inp u t sign al does n o t go below groun d, the input clamp will not operate. this allo ws dac outputs to dire ctly drive the ld6 143 without an a c co uplin g capa citor. wh en the input i s ac-co uple d , the diode cla m p will set the sync tip (or lowest volt age) just below g r o und. the worstca s e syn c tip comp re ssion due to the cla m p will not e x ceed 7 m v. the inp u t level set by the clamp com b i ned with the internal dc offset will keep the output within its acceptable range. for symmetri c sig nal s like chroma, u, v , pb and pr , the average dc bia s is fai r ly consta nt an d the inputs can be ac-coupled with the addition of a pull-up resistor to set the dc input voltage. dac o u tputs can also driv e these same sign als wi th ou t th e ac c o up lin g c a pa c i tor . a c o nc ep tua l illustration of the input clamp circuit is shown figure 2. e-mail: market@ s wid.com.cn www..net
LD6143 three channel 4th order video filter driver swid integrated products, 5.f , bu ilding b, inf o rmation & t e c hnology park, e c onomic & t e c hnological developmen t zon e , ch on g qin g , ch in a. tel: (86 23)62836174 fax: (86 23)62836149 5 figure 2. input clamp circuit i/o configuration for dc-coupled dac drive with dc-coupled output s, use this figure 3 configuration. figure 3. dc-coupled input and output alternatively , if the dac? s averag e dc output level causes the sig nal to exce ed the rang e of 0v to 1.4v , it can be ac-coupled as follows figure 4. figure 4. ac-coupled input, dc-coupled output whe n the l d 6143 i s drive n by an un kn own exte rnal sou r ce or a scar t swit ch with it s own clamping circuitry the input s should be ac-coupled like this figure 5. figure 5. scart w i th dc-coupled output e-mail: market@ s wid.com.cn www..net
LD6143 three channel 4th order video filter driver swid integrated products, 5.f , bu ilding b, inf o rmation & t e c hnology park, e c onomic & t e c hnological developmen t zon e , ch on g qin g , ch in a. tel: (86 23)62836174 fax: (86 23)62836149 6 the sam e method ca n be use d for biased sign als wi t h the addition of a pull-up resi stor to make sure the clam p never ope rates. the i n te rnal p u ll-d o wn re sist an ce i s 80 0k ? 20 % so the exte rnal resist ance should be 7.5m ? to set the dc level to 500mv , as follows figure 6. figure 6. biased scart w i th dc-coupled output the same circuit s ca n be use d with ac-co uple d out p u t s if de sire d. as follows fi gure 7, figure 8 and figure 9. figure 7. dc-coupled inputs, ac-coupled output figure 8. ac-coupled input and output figure 9. biased scart w i th ac-coupled output note: th e video tilt or lin e time disto r tio n w ill be dom inated by the ac-cou pling ca p a citor . th e value may need to be incre a se d beyond 220f in ord e r to obt ain satisfacto ry op eration in so me applications. e-mail: market@ s wid.com.cn www..net
LD6143 three channel 4th order video filter driver swid integrated products, 5.f , bu ilding b, inf o rmation & t e c hnology park, e c onomic & t e c hnological developmen t zon e , ch on g qin g , ch in a. tel: (86 23)62836174 fax: (86 23)62836149 7 pow e r dissipation the ld614 3 output drive configu r atio n must be consi dered when cal c ul ating overall p o we r dissip ation. care mu st b e t a ken n o t to ex ce ed the maximum di e jun c tion te mperature. t he followin g exa m ple can be use d to cal c ulate th e l d 61 43? s po wer di ssip atio n and i n tern al temperature rise. t j =t a p d ? ja where: t a = entironment t e mperature, ja = thermal resist ance p d = p ch1 p ch2 p ch3 and p chx = v cc ? i ch
v out 2 / r l where: v out = 2v in 0.280v i ch =
i cc / 3
v out / r l v in = rms value of input signal i cc = supply current v cc = supply voltage r l = channel load resist ance board layout can al so af fect thermal ch ara c teri st ics. refer to the layout con s id eration s se cti o n for more information. the l d 61 43 is spe c ified t o ope rate with output current s typi cally less than 50 ma, more th an suf f icie nt for a dual (75 ? ) video load. i n ternal amplif iers are cu rre n t limited to a maximum of 100ma and should with st a nd bri e f du rati on short circu i t conditio n s, however thi s ca p ability is n o t guaranteed. lay out consideration gene ral l a yo ut and su ppl y byp a ssin g play majo r roles i n hig h freque ncy pe rforma nce a n d thermal characteri stics. following this layout configurat ion will provide the optim um perform ance and the r mal cha r a c teri stics. for o p tim u m re sult s, follow the ste p s b e lo w a s a basi s for h i gh frequency layout: ? include 1f and 0.1f ceramic byp a ss cap a citors ? place the 1f cap a citor within 0.75 inches of the power pin ? place the 0.1f cap a citor within 0.1 inches of the power pin ? for multi-layer boards, use a large ground plane to help dissip a te heat ? for 2 layer boards, use a ground plane that ex tends beyond the device by at least 0.5? ? minimize all trace lengths to reduce series induct ances e-mail: market@ s wid.com.cn www..net
LD6143 three channel 4th order video filter driver swid integrated products, 5.f , bu ilding b, inf o rmation & t e c hnology park, e c onomic & t e c hnological developmen t zon e , ch on g qin g , ch in a. tel: (86 23)62836174 fax: (86 23)62836149 8 typical application as follows fi gure 10, ci rcuit may be u s ed fo r di rect dc-coupl ed drive by da cs with a n out put volt age ra nge of 0v to 1.4 v . ac-co uple d or dc-co u p l ed output s m a y be use d with ac-coupl e d output s of fering slightly lower power dissip a tion. figure 10. ty pical application diagram e-mail: market@ s wid.com.cn www..net
LD6143 three channel 4th order video filter driver swid integrated products, 5.f , bu ilding b, inf o rmation & t e c hnology park, e c onomic & t e c hnological developmen t zon e , ch on g qin g , ch in a. tel: (86 23)62836174 fax: (86 23)62836149 9 package dimension soic 8-lead small outline package note: all dimensions are in millimeters. take care! this is esd sensitive device, observe the same precautions that you would use with other esd sensitive devices. e-mail: market@ s wid.com.cn www..net
|
