_______________general description the max4117 evaluation kit (ev kit) simplifies evalua- tion of the max4117 dual, high-speed, current-mode feedback amplifiers. the ev kit circuit demonstrates the max4117 in the noninverting configuration set to a gain of 2v/v. rf-style connectors (sma) and 50 terminat- ing resistors are included. the ev kit comes with the max4117 installed. to evalu- ate the max4118, simply order a free sample (max4118esa), replace the max4117 with the max4118 on the ev board, and change the gain-setting resistors for the desired gain. the minimum closed-loop gain for the max4118 is 8v/v. ____________________________features ? optimized for less than -70db crosstalk at 10mhz ? adjustable gain ? fully assembled and tested evaluates: max4117/max4118 max4117 evaluation kit ________________________________________________________________ maxim integrated products 1 19-1131; rev 0; 9/96 part temp. range board type MAX4117EVKIT +25? surface mount qty description c1, c2 2 c3, c4 2 ina, inb, outa, outb 4 sma connectors r1, r2, r3, r4 4 49.9 , 1% resistors rfa, rfb, rga, rgb 4 499 , 1% resistors u1 1 max4117esa none 1 max4117 ev kit pc board none 1 max4112/max4113/max4117/ max4118 data sheet 10?, 10v, 20% tantalum capacitors avx tajb106m010 sprague 293d106x0010b 0.1?, 10% ceramic capacitors vitramon vj1206y104kxx supplier phone fax avx sprague vishay/vitramon (803) 946-0690 (603) 224-1961 (203) 268-6261 (803) 626-3123 (603) 224-1430 (203) 452-5670 ______________component suppliers designation ____________________component list ______________ordering information for free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800 _________________________quick start the max4117 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) connect the +5v supply to the vcc pad and the -5v supply to the vee pad. connect the power-supply ground to the gnd pad. 2) apply a signal of ?.55v max to either input marked ina or inb. 3) connect the appropriate output (outa or outb) for the input selected in step 2, to an oscilloscope through a terminated 50 cable. 4) verify the output signal on the oscilloscope. note: to evaluate the max4118, request a max4118esa sample.
_______________detailed description voltage-gain adjustment the max4117? 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 for the desired gain. 2) install r f and r g . layout considerations the max4117 ev kit layout has been optimized to mini- mize crosstalk of high-speed signals. careful attention has been given to grounding, power-supply bypassing, and signal-path layout. small surface-mount, ceramic bypass capacitors (c1, c2) are placed as close to the max4117 supply pins as possible. to reduce crosstalk, the feedback resistors are kept apart. the ground plane has been removed under and adjacent to the max4117 to reduce stray capacitance. use the alternative layouts shown in figures 5, 6, and 7 to achieve up to 500mhz bandwidth. this layout pro- vides higher bandwidth at the expense of crosstalk. the removal of ground plane around the input sma connectors reduces distortion. refer to the layout and power-supply bypassing section of the max4117 data sheet for further details. evaluates: max4117/max4118 max4117 evaluation kit 2 _______________________________________________________________________________________ table 1. gain-set resistors max4117 a b 3 2 rga
499 w r1
49.9 w ina inb outb outa rfa
499 w rfb
499 w r4
49.9 w r3
49.9 w rgb
499 w r2
49.9 w 1 ina+ 8 4 v ee vee v cc vcc c1
0.1 m f c2
0.1 m f c4
10 m f
10v c3
10 m f
10v inb+ 5 6 7 inb- outb ina- outa
u1 figure 1. max4117 ev kit schematic max4118 20 499 75 26 max4118 max4117 device 56 499 r g ( ) 499 499 r f ( ) 160 10 330 2 small-signal bandwidth (mhz) gain
evaluates: max4117/max4118 max4117 evaluation kit _______________________________________________________________________________________ 3 figure 2. max4117 ev kit component placement guide component side figure 3. max4117 ev kit pc board layout?omponent side figure 4. max4117 ev kit pc board layout?older side
maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circuit 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 1996 maxim integrated products printed usa is a registered trademark of maxim integrated products. evaluates: max4117/max4118 max4117 evaluation kit figure 7. component placement guide?omponent side figure 8. component placement guide?older side figure 5. pc board layout?omponent side figure 6. pc board layout?older side
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