general description the max7443/max7444 are low-cost, triple-channel video reconstruction filters for s-video and cvbs video signals. these devices are ideal for anti-aliasing and dac smoothing video applications such as set-top boxes, dvd players, hard-disk recorders (hdrs), and personal video recorders. these filters operate from a single +5v supply. they are optimized for ntsc, pal, and standard-definition digital tv (sdtv) video systems. each channel consists of a lowpass filter and an adjustable-gain output buffer capable of driving two standard 150 ? video loads. the output buffers can drive either an ac or a dc load such that the blanking level voltage after the backmatch resistor is less than 1v. the y and c video inputs are summed to produce the com- posite video output. the max7444 offers high- frequency boost to improve picture sharpness. the max7443 has a maximum flat-frequency response. the max7443/max7444 are available in a tiny 8-pin thin qfn and an 8-pin so package with exposed pad, and are fully specified over the -40? to +85? extended temperature range. applications features ? triple-channel filter and buffer for cvbs and y/c (s-video) ? filter response ideal for ntsc, pal, and interlaced sdtv signals ? 41db (typ) stopband attenuation at 27mhz ? -0.3db (typ) passband response ? low blanking level voltage allows dc-coupled output ? each channel drives two 150 ? video loads ? +5v single-supply voltage ? tiny 8-pin thin qfn or 8-pin so packages max7443/max7444 triple-channel video reconstruction filter and buffer for composite and y/c outputs ________________________________________________________________ maxim integrated products 1 ordering information 19-2749; rev 1; 1/06 for pricing, delivery, and ordering information, please contact maxim/dallas direct! at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. evaluation kit available part pin-package top mark pkg code max7443 eta 8 thin qfn-ep* afx t833-1 max7443esa 8 so-ep* s8e-12 max7444 eta 8 thin qfn-ep* afy t833-1 max7444esa 8 so-ep* s8e-12 d/a cin lowpass filter lowpass filter yin d/a 6db/ 9.5db/ 12db 6db/ 9.5db/ 12db 6db/ 9.5db/ 12db gset cout cvout yout * * * * * * *optional gnd v cc encoder max7443 max7444 functional diagram set-top boxes/hdr/dvd security cameras/digital cameras game consoles digital vcrs every composite, s-video output for ntsc, pal, sdtv note: all devices specified over -40? to +85? temperature range. * ep = exposed pad. selector guide appears at end of data sheet.
max7443/max7444 triple-channel video reconstruction filter and buffer for composite and y/c outputs 2 _______________________________________________________________________________________ absolute maximum ratings stresses beyond those listed under ?bsolute maximum ratings?may cause permanent damage to the device. these are stress rating s only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specificatio ns is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. v cc to gnd ...........................................................................+6v all other pins to gnd.................................-0.3v to (v cc + 0.3v) maximum current into any pin except v cc and gnd .....?0ma continuous power dissipation (t a = +70?) 8-pin thin qfn (derate 24.4mw/? above +70?) ...1951mw 8-pin so (derate 18.9mw/? above +70?)..............1509mw operating temperature range ...........................-40? to +85? storage temperature range .............................-65? to +150? junction temperature ......................................................+150? lead temperature (soldering, 10s) .................................+300? electrical characteristics (v cc = +5v ?%, c l = 0 to 20pf, r l = 75 ? to gnd for dc-couple, r l = 75 ? to v cc /2 for ac-couple, c yin = c cin = 0.1?, t a = t min to t max , gset = gnd (6db) and v cc (9.5db), unless otherwise noted. typical values are at t a = +25?.) parameter symbol conditions min typ max units max7443 -0.8 -0.3 +0.1 passband response f = 100khz to 4.2mhz, relative to 100khz max7444 -0.1 +0.6 +0.92 db stopband attenuation a sb f = 27mhz 39 41 db boost amplitude f = 4.2mhz, max7444 0.6 db differential gain dg 5-step modulated staircase gain = 6db, 9.5db, 12db 0.15 0.4 % differential phase d 5-step modulated staircase gain = 6db, 9.5db, 12db 0.15 0.4 degrees signal-to-noise ratio snr peak signal (2v p-p ) to rms noise, f = 100hz to 50mhz gain = 6db, 9.5db, 12db 67 73 db max7443 8 20 group delay deviation ? t g deviation from 100khz to 4.1mhz max7444 12 30 ns line-time distortion h dist 18?, 100 ire bar 0.3 % field-time distortion v dist 130 lines, 18?, 100 ire bar 0.5 % clamp settling time to ?% 430 lines yout 0.6 0.8 1.0 cvout 0.6 0.8 1.0 output dc clamp level cout 1.44 1.6 1.97 v low-frequency gain accuracy a v f = 100khz, relative to 6db -3.5 +2 % group delay matching t g(match) low-frequency channel-to-channel matching, f = 100khz for yout and cout 2ns channel-to-channel crosstalk x talk f = 100khz to 3.58mhz, gain = 6db 61 db input leakage current i in 10 ?
max7443/max7444 triple-channel video reconstruction filter and buffer for composite and y/c outputs _______________________________________________________________________________________ 3 electrical characteristics (continued) (v cc = +5v ?%, c l = 0 to 20pf, r l = 75 ? to gnd for dc-couple, r l = 75 ? to v cc /2 for ac-couple, c yin = c cin = 0.1?, t a = t min to t max , gset = gnd (6db) and v cc (9.5db), unless otherwise noted. typical values are at t a = +25?.) parameter symbol conditions min typ max units y inp-p gset = gnd (6db) 1.2 input dynamic swing c inp-p gset = gnd (6db) 0.9 v p-p supply supply voltage range v cc 4.75 5.25 v supply current i cc v cc = +5.25v, no load 88 110 ma power-supply rejection ratio psrr v in = 100mv p-p , f = 0 to 3.5mhz 33 db typical operating characteristics (v cc = +5v, t a = +25?, unless otherwise noted.) -80 1 10 100 amplitude vs. frequency max7443/44 toc01 frequency (mhz) amplitude (db) -60 -20 -40 0 normalized to 0db -2.0 0.1 1 10 passband amplitude vs. frequency max7443/44 toc02 frequency (mhz) amplitude (db) 0.5 -0.5 2.0 normalized to 0db 1.5 1.0 -1.5 -1.0 0 max7443 max7444 -200 0.1 1 10 phase response vs. frequency max7443/44 toc03 frequency (mhz) phase (degrees) 50 -50 200 150 100 -150 -100 0 40 0.1 1 10 group delay vs. frequency max7443/44 toc04 frequency (mhz) group delay (ns) 70 60 90 80 50 2t response (1 ire = 7.14mv) max7443/44 toc05 200ns/div y in 200mv/div y out 400mv/div modulated 12.5t response (1 ire = 7.14mv) max7443/44 toc06 400ns/div y in 200mv/div y out 200mv/div
max7443/max7444 triple-channel video reconstruction filter and buffer for composite and y/c outputs 4 _______________________________________________________________________________________ 65 70 80 75 85 90 -40 10 -15 35 60 85 supply current vs. temperature max7443/44 toc07 temperature ( c) supply current (ma) differential gain max7443/44 toc08 differential phase (degrees) 13 245 6 7 13 245 6 7 0.2 0.3 0.1 0 -0.1 -0.2 -0.3 differential gain (%) 0.2 0.3 0.1 0 -0.1 -0.2 -0.3 differential phase multiburst response max7443/44 toc09 yin 200mv/div yout 200mv/div 10 s/div typical operating characteristics (continued) (v cc = +5v, t a = +25?, unless otherwise noted.) detailed description the primary function of the max7443/max7444 is to fil- ter and buffer the encoder dac outputs that contain digital video information in applications such as set-top boxes, hard-disk recorders, dvd players, and digital vcrs. these devices reconstruct and clean up analog video signals. each max7443/max7444 consists of a lowpass filter and an adjustable-gain output video buffer that is capable of driving two standard 150 ? video loads. the luma (yin) and chroma (cin) video inputs are summed internally to provide the composite (cvout) video output. these devices operate from a single +5v supply. the filters have a nominal cutoff frequency optimized for ntsc, pal, and sdtv. filter filter response the reconstruction filter consists of two 2nd-order sallen-key stages. the butterworth-type response fea- tures a maximally flat passband for ntsc and pal bandwidths. the stopband offers 41db (typ) of attenua- tion at sampling frequencies of 27mhz and above (see typical operating characteristics ). high-frequency boost the high-frequency boost available in the max7444 compensates for signal degradation and rolloff in the video encoder, which increases the image sharpness. the max7443 has a flat response over the video band- width. output buffer the output buffer drives two 150 ? video loads with a 2v p-p signal. the adjustable gain of the output buffer provides a gain of 6db, 9.5db, and 12db, which are selected by tying the gset pin to gnd, v cc , or float- ing, respectively. the max7443/max7444 can drive an ac load or drive the video load directly without using the large output capacitor. the output buffer drives a dc load with an output blanking level of less than 1v. pin name function 1 yin luma (y) input 2 gset gain-setting control input. see table 1 for values. 3 cin chroma (c) input 4 gnd ground 5v cc 5v power supply 6 cout chroma (c) output 7 cvout composite video output 8 yout luma (y) output pin description
12db gain setting the gset pin is biased internally to v cc /2 through two 100k ? resistors from v cc to gnd. the internal imped- ance at the node is 50k ? . no additional connection is necessary since the pin offers a minimum noise margin immunity of 1v p-p . output clamp level when sync pulses in the luma signal (y) are detected, the dc restore loop is activated. the function of the loop is to set the sync tip of the video signal to the desired dc level of 0.8v for yout and cout and the average dc voltage of cout at 1.6v. applications information input considerations use a 0.1? ceramic capacitor to ac-couple the input to the max7443/max7444. this input capacitor stores a dc level such that the outputs are clamped to the appropriate dc voltage level. output considerations the outputs of the max7443/max7444 are typically connected to a 75 ? series back-match resistor fol- lowed by the video cable. because of the inherent divide by two of this configuration, the blanking level of the video cable is always less than 1v, which complies with industry-standard video requirements. the video buffer can also drive an ac-coupled video load. good video performance is achieved with an output capacitor as low as 220?. power-supply bypassing and layout the max7443/max7444 operate from a single +5v supply. bypass v cc to gnd with a 0.1? capacitor. place all external components as close to the device as possible. refer to the max7443 evaluation kit for a proven pc board layout example. exposed pads both the so and thin qfn packages of the max7443/ max7444 have exposed pads on the bottom of the packages. these pads are electrically connected to gnd and should be connected to the ground plane for improved thermal conductivity. do not route signals under these packages. chip information transistor count: 4252 process: bicmos max7443/max7444 triple-channel video reconstruction filter and buffer for composite and y/c outputs _______________________________________________________________________________________________________ 5 gset gain (db) gnd 6 v cc 9.5 open 12 table 1. gain-setting control cout v cc gnd 1 2 8 7 yout cvout gset cin yin 3 4 6 5 thin qfn top view cout v cc gnd 1 2 8 7 yout cvout gset cin yin 3 4 6 5 so max7443 max7444 max7443 max7444 pin configurations selector guide part high-frequency boost max7443eta no max7443esa no max7444eta yes max7444esa yes
max7443/max7444 triple-channel video reconstruction filter and buffer for composite and y/c outputs 6 _______________________________________________________________________________________ 8l, soic exp. pad.eps c 1 1 21-0111 package outline 8l soic, .150" exposed pad package information (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline info rmation, go to www.maxim-ic.com/packages .)
max7443/max7444 triple-channel video reconstruction filter and buffer for composite and y/c outputs _______________________________________________________________________________________ 7 package information (continued) (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline info rmation, go to www.maxim-ic.com/packages .) 6, 8, &10l, dfn thin.eps
max7443/max7444 triple-channel video reconstruction filter and buffer for composite and y/c outputs maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circu it patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. 8 _____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2006 maxim integrated products printed usa is a registered trademark of maxim integrated products. package information (continued) (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline info rmation, go to www.maxim-ic.com/packages .) common dimensions symbol min. max. a 0.70 0.80 d 2.90 3.10 e 2.90 3.10 a1 0.00 0.05 l 0.20 0.40 pkg. code n d2 e2 e jedec spec b [(n/2)-1] x e package variations 0.25 min. k a2 0.20 ref. 2.00 ref 0.250.05 0.50 bsc 2.300.10 10 t1033-1 2.40 ref 0.200.05 - - - - 0.40 bsc 1.700.10 2.300.10 14 t1433-1 1.500.10 mo229 / weed-3 0.40 bsc - - - - 0.200.05 2.40 ref t1433-2 14 2.300.10 1.700.10 t633-2 6 1.500.10 2.300.10 0.95 bsc mo229 / weea 0.400.05 1.90 ref t833-2 8 1.500.10 2.300.10 0.65 bsc mo229 / weec 0.300.05 1.95 ref t833-3 8 1.500.10 2.300.10 0.65 bsc mo229 / weec 0.300.05 1.95 ref 2.300.10 mo229 / weed-3 2.00 ref 0.250.05 0.50 bsc 1.500.10 10 t1033-2
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