_________________________quick start the max477 ev kit is fully assembled and tested. follow these steps to verify board operation. do not turn on the power supply until all connections are completed: 1) the circuit requires supply voltages of ?v. connect the +5v supply to the v+ pad, and the -5v supply to the v- pad. connect power-supply ground to the pad marked gnd. 2) apply a signal of ?.0v maximum to the sma con- nector marked in. 3) connect the output marked out to an oscilloscope through a terminated 75 ? cable. 4) turn on the power supply and verify the output sig- nal on the oscilloscope. detailed description shutdown control although the ev kit provides shutdown-control circuitry (j1) for other amplifiers, the max477 does not have a shutdown feature. voltage-gain adjustment the max477? gain can be adjusted with minor modifi- cations to the evaluation board: 1) select feedback (r f ) and gain set (r g ) resistors from table 1. 2) install r f and r g . general description the max477 evaluation kit (ev kit) simplifies evaluation of the max477, a 300mhz high-speed amplifier. its cir- cuit includes the max477 in the noninverting configura- tion set to unity gain. rf-style connectors (sma) and 75 ? terminating resistors are included for compatibility with video test equipment. ____________________________features 300mhz -3db bandwidth optional adjustable gain fully assembled and tested evaluates: max477 max477 evaluation kit ________________________________________________________________ maxim integrated products 1 part temp. range ic package MAX477EVKIT-so +25? surface mount qty description c1, c6 2 c3, c4 2 1000pf ?0% ceramic capacitors vitramon vj1206y102kxx c2, c5 2 r1, r2 2 75 ? ?% resistors rf 1 in, out 2 none 1 0.1? ?0% ceramic capacitors vitramon vj1206y104kxx 10? ?0% 10v tantalum capacitors avx tajb106m010 sprague 293d106x0010b supplier phone fax avx 803-946-0690 803-626-3123 component suppliers designation 0 ? resistor sma connectors high-frequency amplifier pc board component list ordering information table 1. gain-set resistors 1 0 2 500 open 300 500 120 5 125 500 25 10 50 450 12 gain r f ( ? ) r g ( ? ) small-signal bandwidth (mhz) 19-0467; rev. 3; 11/99 sprague 603-224-1961 603-224-1430 vishay/vitramon 203-268-6261 203-452-5670 u1 1 max477esa for price, delivery, and to place orders, please contact maxim distribution at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com.
evaluates: max477 layout considerations the max477 ev kit layout is optimized for high-speed signals. careful attention was given to grounding, power-supply bypassing, and signal-path layout. small surface-mount ceramic capacitors are placed as close to the max477 supply pins as possible. no-connect pins 1 and 5 are grounded to prevent unwanted noise from coupling into the circuit. refer to the grounding, bypassing, and pc board layout section of the max477 data sheet for further details. max477 evaluation kit 2 _______________________________________________________________________________________ max477 in shdn enable disable u1 gnd c4 1000pf c5 0.1 f c2 0.1 f c1 10 f 10v c3 1000pf rg open rf 0 ? r2 75 ? r1 75 ? c6 10 f 10v out v+ j1 1 2 3 3 2 4 5 1 6 7 8 v- shdn not applicable for max477 figure 1. max477 ev kit schematic
evaluates: max477 max477 evaluation kit _______________________________________________________________________________________ 3 figure 2. max477 ev kit component placement guide component side figure 3. max477 ev kit component placement guide solder side figure 4. max477 ev kit pc board layout?omponent side figure 5. max477 ev kit pc board layout?older side
evaluates: max477 max477 evaluation kit 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. 4 _____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 1999 maxim integrated products printed usa is a registered trademark of maxim integrated products.
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