general description the max4383 evaluation kit (ev kit) demonstrates the capability of the high-speed max4383 op amp config- ured in a 5-pole, lowpass, multiple feedback (rauch) filter that provides a butterworth response with a band- width of -3db at 30mhz (typ). this circuit can be used for video anti-aliasing and reconstruction filtering for hdtv, progressive dvd, and xga resolution graphics displays. the max4383 ev kit is designed to drive a 75 ? back-terminated load, common in video applica- tions, with an overall gain of 1. the max4383 ev kit is a fully assembled and tested surface-mount board that operates from either a +5v single supply or 5v dual supplies. features video filter solution for atsc and high- resolution graphics applications 5-pole active multiple feedback (rauch) video filter 30mhz bandwidth at -3db (typ) >40db attenuation at 74.25mhz +5v single-supply or 5v dual-supply operation surface-mount construction fully assembled and tested eliminates costly inductors with more accurate r-c components evaluates: max4383 max4383 evaluation kit ________________________________________________________________ maxim integrated products 1 19-2792; rev 0; 3/03 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. ordering information simplified circuit typical application circuit part temp range ic package MAX4383EVKIT 0? to +70? 14 tssop lowpass filter g = 2v/v display z o = 75 ? dac r16 dac load r15 mpeg encoder max4383 ev kit does video u1c u1b u1d u1a r14 input output r1 r3 r5 r6 r15 c1 c4 r13 r12 r2 r7 r11 r9 r10 r16 r4 c6 c2 c3 c5 r8 v ee v cc v ee v cc v ee v cc v ee v cc
evaluates: max4383 max4383 evaluation kit 2 _______________________________________________________________________________________ quick start required equipment: ? dual 5.0v dc power supply ? signal generation platform (e.g., tektronix tg 2000) ? video measurement set (e.g., tektronix vm 700a) the max4383 ev kit is a fully assembled and tested surface-mount board. follow the steps below for board operation. do not turn on the power supply until all connections are completed. procedures 1) connect the output from the 75 ? video signal gener- ator to the input bnc connector on the ev kit. 2) connect the input of the 75 ? video measurement set to the output bnc connector on the ev kit. 3) connect the +5.0v supply to the vcc pad. connect ground to the gnd pad. 4) connect the -5.0v supply to the vee pad. for single- supply (+5.0v) operation, connect vee to ground and bias the input appropriately. 5) set the signal generator for multiburst sweep. 6) turn on the 5.0v dc power supply. 7) analyze the filtered output signal with the vm700 video measurement set. note: the generator (signal source) and the video test set (load) must be 75 ? terminated, and the signal source must also provide a dc return to ground. this is the function of r16 and r15, respectively. these resis- tors are set to 75w in the max4383 ev kit. if a 50 ? sys- tem is used, r16 must be changed to 50 ? . if a 50 ? analyzer is used, r15 must be 50 ? . the dac must sup- ply a dc voltage to bias the input of the max4383. if your dac has insufficient bias to do this, add a 5.6k ? resistor between vcc and the junction of r16 and r14. component suppliers supplier phone fax website murata 770-436-1300 770-436-3030 www.murata.com taiyo yuden 800-348-2496 847-925-0899 www.t-yuden.com tdk 847-803-6100 847-390-4405 www.component.tdk.com component list designation qty description c1, c4 2 3.3pf 0.25pf, 50v c0g ceramic capacitors (0603) tdk c1608c0g1h3r3ct c2 1 68pf 5%, 50v c0g ceramic capacitor (0603) murata grm1885c1h680j or tdk c1608c0g1h680jt c3 1 27pf 5%, 50v c0g ceramic capacitor (0603) murata grm1885c1h270j or tdk c1608c0g1h270jt c5 1 33pf 5%, 50v c0g ceramic capacitor (0603) taiyo yuden umk107cg330jz or tdk c1608c0g1h330jt c6 1 100pf 5%, 50v c0g ceramic capacitor (0603) murata grm1885c1h101j tdk c1608c0g1h101jt c7, c9 2 10f 20%, 6.3v x5r ceramic capacitors (0805) taiyo yuden jmk212bj106mg or tdk c2012x5r0j106m c8, c10 2 0.1f 10%, 25v x7r ceramic capacitors (0603) tdk c1608x7r1e104k r1, r2, r4, r5, r7 r13 11 210 ? 1% resistors (0805) r3 1 100 ? 1% resistor (0805) r6 1 121 ? 1% resistor (0805) r14, r15, r16 3 75 ? 1% resistors (0805) r17 0 not installed, resistor (0805) u1 1 max4383eud (14-pin tssop) input, output 2 bnc connectors none 1 max4383 pc board please indicate that you are using the max4383 when contacting these suppliers.
evaluates: max4383 max4383 evaluation kit _______________________________________________________________________________________ 3 detailed description the max4383 ev kit is a fully assembled and tested surface-mount circuit board that demonstrates the capability of the high-speed max4383 op amp config- ured in a 5-pole, active lowpass multiple feedback filter circuit. the filter can be used for video anti-aliasing or as a reconstruction filter for atsc (hdtv) or high-reso- lution (xga) graphics. the circuit has a 75 ? dac load (r16), a gain of 2v/v, and a 75 ? source (r15) for dri- ving a 75 ? back-terminated load to an overall gain of 1. the board operates from either a +5v single supply or 5v dual supplies. the max4383 ev kit demonstrates a lower cost, but more accurate way to design video filters. using r-c, rather than l-c components, it provides a 30mhz, -3db bandwidth with >40db rejection at 74.25mhz (figure 1), as well as group-delay compensation and buffering using a single max4383 quad op amp. the improved tolerance of r-c, versus l-c components, removes the need for production tuning. some initial tuning may be required to account for the variation in the dac load and parasitic components due to pc board layout differ- ences. the max4383 ev kit uses dual supplies, but the max4383 can be run from a single supply. the max4383 ev kit is a rauch, or multiple feedback realization of a 5-pole modified legendre characteristic using one 1st-order +6db gain stage and two 2nd-order unity-gain stages. the final stage is a 1st-order group delay compensator, which drives the back-terminated 75 ? load to an overall unity gain. there are three sensi- tive points in the circuit; r14, which controls the real pole, c1 and c4, that control the high-frequency poles, and c5 that sets the group delay compensation. the max4383 ev kit comes with a 75 ? termination (r16) and a bnc connector (input) in place of the dac nor- mally found at the input for measurement purposes, and this reduces the gain to -6db overall. the values of r14 and r16 are based on the dac with a typical load resis- tance of 25 ? to 35 ? . to accommodate different load resistors, adjust the value of the r14 and the c6 product accordingly. the values of c1 and c4 reflect a two-sided pc board with minimal ground plane around the op amps pins. c5 adjusts the group delay compensation. adjust the value of c1 and c4 for bandwidth before adjusting c5 for group-delay variation compensation. 5 110 100 gain vs. frequency max4383ev fig01 frequency (mhz) gain (db) -45 -35 -25 -15 -5 -10 -20 -30 -40 0 figure 1. gain vs. frequency response of the ev kit filter
evaluates: max4383 max4383 evaluation kit 4 _______________________________________________________________________________________ max4383 u1 ina+ 3 2 1 6 5 7 v cc v ee vcc gnd c7 10 f c8 0.1 f c10 0.1 f c9 10 f r15 75 ? output vee outd ind- 11 14 12 8 10 9 13 bnc r17 open r11 210 ? c6 100pf r14 75 ? input bnc r13 210 ? r3 100 ? r16 75 ? c1 3.3pf r5 210 ? r4 210 ? c2 68pf r12 210 ? r1 210 ? r2 210 ? c5 33pf r8 210 ? r10 210 ? c4 3.3pf r6 121 ? r9 210 ? r7 210 ? c3 27pf 4 ind+ outc inc+ inc- ina- outa inb- inb+ outb all resistors are 1%. figure 2. max4383 ev kit schematic
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 ? 2003 maxim integrated products printed usa is a registered trademark of maxim integrated products. evaluates: max4383 max4383 evaluation kit evaluates: max4383 figure 3. max4383 ev kit component placement guide component side figure 4. max4383 ev kit pc board layout?omponent side figure 5. max4383 ev kit pc board layout?older side figure 6. max4383 ev kit component placement guide solder side
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