general description the MAX11500 integrated three-channel high-definition (hd) video filter includes input video clamps and output buffers. this device is ideal for anti-aliasing and dac smoothing video applications such as set-top boxes, hard-disk recorders (hdrs), dvd players, and person- al video recorders. the 6th-order channel filters have a typical -3db band- width of 33mhz. each channel has an output buffer with a gain of +6db and can drive a full 2v p-p video signal into one standard 150 ? video load. these buffers can drive either an ac- or dc-coupled load such that the blanking level voltage after the backmatch resistor is less than 1v. the video inputs feature a transparent clamp for ac- and dc-coupled input signals. if the input signal does not go below ground, the input clamp is inactive, thus enabling dac outputs to be dc-coupled to the input. the device operates from a single +5v supply, is offered in the upper commercial 0? to +85? temperature range, and is available in a small 8-pin so package. applications high-definition set-top box receivers hd television sets hd recorders dvd players personal video recorders video-on-demand features ? three-channel 6th-order filter for high-definition video ? +6db output buffers ? transparent input clamps ? ac- or dc-coupled inputs ? ac- or dc-coupled outputs ? output buffers drive one standard 150 ? video load ? 12kv hbm esd protection on outputs ? single +5v power supply ? small 8-pin so package MAX11500 three-channel, high-definition video filter ________________________________________________________________ maxim integrated products 1 out3 gnd v cc 1 2 8 7 out1 out2 in2 in3 in1 so + top view 3 4 6 5 MAX11500 pin configuration in1 out1 gnd v cc 33mhz transparent clamp +6db in2 out2 33mhz transparent clamp +6db in3 out3 33mhz transparent clamp +6db MAX11500 typical operating circuit 19-3212; rev 0; 1/08 for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. ordering information + denotes a lead-free package. part temp range pin- package pkg code MAX11500usa+ 0? to +85? 8 so s8-2 evaluation kit available
MAX11500 three-channel, high-definition video filter 2 _______________________________________________________________________________________ absolute maximum ratings electrical characteristics (v cc = +5v, r load = 150 ? to gnd, c in = 0.1?, t a = 0? to +85?, unless otherwise specified. all frequency response is relative to 100khz.) 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. note 1: all devices are 100% production tested at t a = +25?. v cc to gnd ..............................................................-0.3v to +6v all other pins to gnd ......-0.3v to the lower of (v cc + 0.3v) and +6v continuous power dissipation (t a = +70?) 8-pin so (derate 5.9mw/? above +70?)...............470.6mw maximum current into any pin except v cc and gnd......?0ma operating temperature range MAX11500usa ...................................................0? to +85? storage temperature range .............................-65? to +150? lead temperature (soldering, 10s) .................................+300? junction temperature ......................................................+150? parameter symbol conditions min typ max units -1db bandwidth f 1db t a = +25? 23 30 mhz -3db bandwidth f 3db 33 mhz f = 37.125mhz 6.5 f = 44.25mhz 15.5 stopband attenuation a sb f = 74.25mhz, t a = +25? 32 48 db low-frequency gain a v 5.4 6.0 6.6 db low-frequency gain matching a v ( match ) 0.01 db input voltage range v in referenced to gnd if dc-coupled 1.7 v v out = 1.4v p-p , f = 10mhz 0.15 v out = 1.4v p-p , f = 15mhz 0.2 total harmonic distortion thd v out = 1.4v p-p , f = 22mhz 0.8 % channel-to-channel crosstalk x talk f = 1mhz -72 db signal-to-noise ratio snr peak signal (2v p-p ) to rms noise, f = 100khz to 30mhz 68 db group delay t g f = 100khz 25 ns group-delay deviation ? t g f = 100khz to 26mhz 8 ns supply voltage range v cc 4.75 5 5.25 v supply current i cc no load 24 38 ma
MAX11500 three-channel, high-definition video filter _______________________________________________________________________________________ 3 magnitude response (passband and stopband) MAX11500 toc01 frequency (mhz) response (db) 10 1 -60 -40 -20 0 20 -80 0.1 100 magnitude response (passband) MAX11500 toc02 frequency (mhz) response (db) 10 1 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 4.0 0.1 100 group delay MAX11500 toc03 frequency (mhz) delay (ns) 10 1 10 20 30 40 50 60 0 0.1 100 2t response MAX11500 toc04 40ns/div 200mv/div 200mv/div hd multiburst response (1mhz?0mhz) MAX11500 toc05 4 s/div 200mv/div 200mv/div hd multiburst response (20mhz?0mhz) MAX11500 toc06 4 s/div 200mv/div 200mv/div typical operating characteristics (v cc = +5v, outputs ac-coupled with 220?, r load = 150 ? to gnd, c in = 0.1?, t a = +25?. all frequency response is relative to 100khz.)
detailed description the MAX11500 integrates three high-definition (hd) video filters, each with a transparent input clamp, a 6th- order lowpass filter with a -3db bandwidth of 33mhz, and an output stage with a gain of 2v/v. the output sig- nal is offset by typically 550mv to optimize driver per- formance. v out = 2 x v in + 0.55v typical voltage waveforms are shown in figures 1 and 2. transparent clamps all inputs feature a transparent clamp that allows either ac- or dc-coupling of the inputs. the clamp remains inactive while the input signal is above ground, offering true dc input coupling. if the signal goes below ground, as is the case if it is ac-coupled, the clamp sets the sync tip close to the ground level. input coupling the choice to ac- or dc-couple the input depends on the video source. many dacs have a current output and are terminated to ground with a resistor; such sig- nals can be conveniently dc-coupled. in cases where the dc level of the video signal is unknown or outside of the specified input range of the MAX11500, such sig- nals require ac-coupling. examples of the latter are scart inputs and dacs terminated to v cc . dc-coupled inputs if the input is dc-coupled, the voltage must remain above zero but not exceed the maximum input voltage of 1.7v (typical). input signal 0.3v 1.0v 0.0v output signal 1.15v 2.55v 0.55v in_ out_ MAX11500 figure 1. typical ac-coupled signal MAX11500 three-channel, high-definition video filter 4 _______________________________________________________________________________________ 4 _______________________________________________________________________________________ pin description pin name function 1 in1 video input channel 1 2 in2 video input channel 2 3 in3 video input channel 3 4v cc power supply. bypass to gnd with 0.1? and 1? capacitors. 5 gnd ground 6 out3 video output channel 3 7 out2 video output channel 2 8 out1 video output channel 1
ac-coupled inputs if the input is ac-coupled, the transparent clamp will be active and sets the sync tip or the lowest voltage of the signal close to ground. this clamping behavior is appropriate for unipolar signals such as y, r, g, or b with or without sync pulse (figure 3). for bipolar signals such as pb, pr signals, the ac-coupled inputs should be biased to a fixed dc voltage to ensure that the transparent clamp never turns on. a suitable network that biases the input to typically 0.59v is shown in figure 4. the device has an input leakage current (i l ) of typically 0.5? and thus the bias voltage is derived as follows: hd filters the internal filters are optimized to deliver a flat pass- band along with high stopband attenuation. the filter characteristic has been chosen to provide an excellent time-domain response with low overshoot. the typical -3db frequency of 33mhz guarantees low attenuation in the passband, while at the same time allowing for a typical attenuation of -48db at 74.25mhz. v r rr vixr bccl ( ) = + ? 2 12 1 MAX11500 three-channel, high-definition video filter _______________________________________________________________________________________ 5 input signal 0.32v 1.02v 0.02v 0.00v output signal 1.19v 2.59v 0.59v in_ out_ MAX11500 figure 2. typical dc-coupled signal in_ MAX11500 0.1 f encoder dac figure 3. ac-coupling for unipolar signals (y, r, g, b) in_ r1 820k ? r2 120k ? MAX11500 0.1 f encoder dac v cc figure 4. ac-coupling for bipolar signals (pb, pr)
MAX11500 three-channel, high-definition video filter 6 _______________________________________________________________________________________ output buffer the MAX11500 features output buffers with +6db gain that drive a standard 150 ? video load. a typical load consists of a 75 ? backmatch resistor, an optional 220? or larger coupling capacitor, and a 75 ? termina- tion resistor. the offset between input and output sig- nals has been chosen such that the blanking level on the output is less than 1v after the backmatch resistor, thus meeting digital tv specifications. this allows the MAX11500 to drive video loads directly without using costly ac-coupling capacitors. applications information output considerations the MAX11500 outputs can be dc- or ac-coupled. the MAX11500, with +6db gain, is typically connected to a 75 ? series backmatch resistor followed by the video cable. if an ac connection is used, choose an ac-coupling capacitor value that ensures that the low- est frequency content in the video signal is passed and the field-time distortion is kept within desired limits. the selection of this value is a function of the input imped- ance and more importantly the input leakage of the cir- cuit being driven. common industry practice is to use a 220? or larger capacitor. the outputs of the MAX11500 are fully protected against a short circuit either to the ground or the posi- tive supply of the device. the short-circuit protection circuitry limits the output current to typically 75ma per output. shorting more than one output simultaneously may exceed the maximum package power dissipation. pcb layout recommendations the device is thermally designed to operate with mini- mum copper. however, to help with heat dissipation, connect the power and ground traces to large copper areas if possible. bypass v cc to gnd with a 0.1? capacitor and an additional 1? capacitor in parallel for additional low-frequency decoupling. using surface- mount capacitors reduces lead inductance and ensures that the impedance of the capacitors is low over a broad range of frequencies. place traces carrying video signals appropriately to avoid mutual coupling. if ac-coupling the inputs, place the input coupling capacitors as close as possible to the device and keep traces short to minimize parasitic capacitance and inductance. doing so extends the performance to the uppermost frequency range possi- ble with the MAX11500. for a recommended pcb layout, refer to the MAX11500 ev kit data sheet.
MAX11500 three-channel, high-definition video filter _______________________________________________________________________________________ 7 in1 0.1 f* 0.1 f1 f 220 f* 1 75 ? 75 ? 75 ? out1 gnd *optional v cc 33mhz clamp encoder +6db 8 MAX11500 dac in2 0.1 f* 220 f* 2 75 ? 75 ? 75 ? out2 33mhz clamp +6db 7 dac in3 0.1 f* 220 f* 3 75 ? 75 ? 75 ? out3 33mhz clamp 5 4 +5v +6db 6 dac typical operating circuit
MAX11500 three-channel, high-definition video filter 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 2008 maxim integrated products is a registered trademark of maxim integrated products, inc. 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: 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 .)
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