general description the MAX7453 is a low-cost, triple-channel video recon- struction filter for s-video and cvbs video-signal appli- cations. this device is ideal for anti-aliasing and dac smoothing video applications such as set-top boxes, dvd players, hard-disk recorders (hdrs), and personal video recorders. this filter operates from a single +5v supply. it is optimized for ntsc, pal, and standard-defi- nition tv (sdtv) video systems. each channel consists of a lowpass filter and an output buffer capable of driving one (yout, cout) or two (cvout) standard 150 ? video loads. the output buffers can drive either an ac or a dc load such that the blank- ing level voltage after the backmatch resistor is less than 1v. the y and c video inputs are summed to produce the composite video output. the MAX7453 has a maxi- mally flat frequency response. the MAX7453 is available in an 8-pin so package and is fully specified over the commercial (0? to +70?) tem- perature range. applications set-top boxes/hdrs/dvds security cameras/digital cameras game consoles digital vcrs every composite, s-video output for ntsc, pal, and sdtv features ? triple-channel filter and buffer for cvbs and y/c (s-video) video signals ? filter response ideal for ntsc, pal, and interlaced sdtv signals ? 42db (typ) stopband attenuation at 27mhz ? -0.3db (typ) passband response ? <1v blanking level allows dc-coupled output ? cvout drives two 150 ? video loads ? yout and cout drive one 150 ? video load ? +5v single-supply voltage ? 8-pin so package MAX7453 triple-channel video reconstruction filter and buffer for composite and y/c outputs ________________________________________________________________ maxim integrated products 1 19-3269; rev 0; 6/05 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. d/a cin lowpass filter lowpass filter yin d/a cout cvout yout * gnd v cc * * * encoder MAX7453 +6db +6db +6db functional diagram ordering information part temp range pin-package MAX7453csa 0? to +70? 8 so cvout cout cin 1 2 8 7 yout v cc n.c. gnd yin so top view 3 4 6 5 MAX7453 pin configuration
MAX7453 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 so ....................................................................522.8mw operating temperature range...............................0? to +70? storage temperature range .............................-65? to +150? junction temperature ......................................................+150? lead temperature (soldering, 10s) .................................+300? electrical characteristics (v cc = +5v ?%, c l = 0 to 20pf, all loads to gnd for dc-couple, all loads to v cc / 2 for ac-couple, c yin = c cin = 0.1?, r yout = 150 ? , r cout = 150 ? , r cvout = 75 ? , t a = t min to t max , unless otherwise noted. typical values are at t a = +25?.) parameter symbol conditions min typ max units passband response f = 100khz to 4.2mhz, relative to 100khz -0.6 -0.27 0db stopband attenuation a sb f = 27mhz 39 42 db chroma/luma gain f = 3.58mhz, reference to cvout at 336khz 96 98 100 % differential gain dg 5-step modulated staircase 0.15 0.5 % differential phase d 5-step modulated staircase 0.15 0.5 degrees signal-to-noise ratio snr peak signal (2v p-p ) to rms noise, f = 100hz to 50mhz 67 73 db line-time distortion h dist 18?, 100ire bar 0.3 % field-time distortion v dist 130 lines, 18?, 100ire bar 0.5 % clamp settling time to ?% 300 lines yout 0.60 0.8 0.95 cvout 0.60 0.8 0.95 output dc clamp level cout 1.44 1.6 1.95 v low-frequency gain accuracy a v f = 100khz, relative to 6db -3.0 +2.0 % group-delay deviation ? t g deviation from 100khz to 4.1mhz 8 16 ns 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 61 db input leakage current i in 10 ? y inp-p 1.2 input dynamic swing c inp-p 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 65 85 ma power-supply rejection ratio psrr v in = 100mv p-p , f = 0 to 3.5mhz 33 db
MAX7453 triple-channel video reconstruction filter and buffer for composite and y/c outputs _______________________________________________________________________________________ 3 amplitude vs. frequency MAX7453 toc01 frequency (mhz) amplitude (db) 10 -70 -60 -50 -40 -30 -20 -10 0 10 -80 1 100 normalized to 0db passband amplitude vs. frequency MAX7453 toc02 frequency (mhz) amplitude (db) 1 -2.5 -2.0 -1.5 -1.0 -0.5 0 0.5 1.0 -3.0 0.1 10 normalized to 0db phase response vs. frequency MAX7453 toc03 frequency (mhz) phase (degrees) 1 -240 -200 -160 -120 -80 -40 0 40 -280 0.1 10 group delay vs. frequency MAX7453 toc04 frequency (mhz) group delay (ns) 1 50 55 60 65 70 75 80 85 90 40 45 0.1 10 2t response (1ire = 7.4mv) MAX7453 toc05 100ns/div yin 200mv/div yout 200mv/div measure at termination modulated 12.5t response (1ire = 7.14mv) MAX7453 toc06 400ns/div yin 500mv/div yout 500mv/div measure at termination supply current vs. temperature MAX7453 toc07 temperature ( c) supply current (ma) 60 35 10 -15 52 54 56 58 60 62 64 66 68 70 50 -40 85 differential gain differential phase MAX7453 toc08 differential gain (%) -0.3 -0.2 0.2 -0.1 0.1 0 0.3 1st 2nd 3rd 4th 5th 6th differential phase (degrees) -0.3 -0.2 0.2 -0.1 0.1 0 0.3 1st 2nd 3rd 4th 5th 6th multiburst response MAX7453 toc09 10 s/div yin 500mv/div yout 500mv/div measured at termination typical operating characteristics (v cc = +5v, t a = +25?, unless otherwise noted.)
detailed description the primary function of the MAX7453 is to filter and buffer the encoder dac outputs that contain digital video information in applications such as set-top boxes, hdrs, dvd players, and digital vcrs. this device reconstructs and cleans up analog video signals. the MAX7453 consists of a lowpass filter and a +6db-gain output video buffer. the luma (yin) and chroma (cin) video inputs are summed internally to provide the com- posite (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 42db (typ) of attenua- tion at sampling frequencies of 27mhz and above (see the typical operating characteristics ). output buffer the yout and cout buffers have a fixed +6db gain capable of driving one standard 150 ? video load with a 2v p-p signal. the cvout buffer has a fixed +6db gain, capable of driving two 150 ? video loads. the MAX7453 can drive an ac load or drive the video load directly without using the large output capacitor. the output buffer of all the channels drives a dc load with an out- put blanking level of less than 1v. 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 to set 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 MAX7453. 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 MAX7453 are typically connected to a 75 ? series back-match resistor followed by the video cable. because of the inherent divide-by-two of this con- figuration, 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 MAX7453 operates 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. the maximum power dissipation listed in the absolute maximum ratings section assumes that the pc board is a multilayer board with ground and power planes. chip information transistor count: 4100 process: bicmos pin name function 1 yin luma (y) input 2n.c. no connection. no internal connection. 3 gnd ground 4 cin chroma (c) input 5 cout chroma (c) output 6 cvout composite video output 7v cc 5v power supply 8 yout luma (y) output pin description MAX7453 triple-channel video reconstruction filter and buffer for composite and y/c outputs 4 _______________________________________________________________________________________
MAX7453 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. maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 _____________________ 5 2005 maxim integrated products printed usa is a registered trademark of maxim integrated products, inc. 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 .) soicn .eps package outline, .150" soic 1 1 21-0041 b rev. document control no. approval proprietary information title: top view front view max 0.010 0.069 0.019 0.157 0.010 inches 0.150 0.007 e c dim 0.014 0.004 b a1 min 0.053 a 0.19 3.80 4.00 0.25 millimeters 0.10 0.35 1.35 min 0.49 0.25 max 1.75 0.050 0.016 l 0.40 1.27 0.394 0.386 d d min dim d inches max 9.80 10.00 millimeters min max 16 ac 0.337 0.344 ab 8.75 8.55 14 0.189 0.197 aa 5.00 4.80 8 n ms012 n side view h 0.244 0.228 5.80 6.20 e 0.050 bsc 1.27 bsc c h e e b a1 a d 0 -8 l 1 variations:
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