_________________________quick start the max4223 ev kit is fully assembled and tested. follow these steps to verify board operation. 1) the circuit requires supply voltages of ?.85v to ?.5v. for evaluation purposes, connect a +5v sup- ply to the pad labeled vcc and a -5v supply to the pad labeled vee. connect the power-supply ground to the pad labeled gnd. 2) verify that the shunt is across pins 1 and 2 of jumper ju1. 3) connect the output labeled out to an oscilloscope input. for best performance, terminate the output with a 50 load. 4) turn on the power supply. apply a signal of ?.5v maximum to the sma connector labeled in. 5) verify the output signal on the oscilloscope. note: when using a 50 -terminated oscilloscope input, the output amplitude observed will be half that of the input, due to the voltage divider formed by the 49.9 back-terminating resistor (r1) and the oscilloscope input termination impedance. _______________general description the max4223 evaluation kit (ev kit) simplifies evalua- tion of the 1ghz, low-power max4223 current-feed- back amplifier. the ev kit circuit demonstrates the max4223 in the noninverting unity-gain configuration. rf-style connectors (sma) and 50 terminating resis- tors are included for test equipment compatibility. the max4223 ev kit uses a pc board design optimized for high-frequency amplifiers. this board can also be used to evaluate the max4224 and other maxim ampli- fiers that share the same pinout . ____________________________features ? 1ghz -3db bandwidth ? 300mhz 0.1db gain flatness ? 1100v/? slew rate ? ?v supply operation ? optional adjustable gain ? high-impedance shutdown mode ? fully assembled and tested evaluates: max4223/max4224 max4223 evaluation kit ________________________________________________________________ maxim integrated products 1 19-1281; rev 0; 8/97 qty description c1, c2 2 0.1?, 10% ceramic capacitors c3, c4 2 10?, 10v, 20% tantalum capacitors avx tajb106m010 or sprague 293d106x0010b r1, r2 2 49.9 , 1% resistors rf 1 560 , 5% resistor rg 0 open supplier phone fax avx (803) 946-0690 (803) 626-3123 ______________component suppliers designation ____________________component list ______________ordering information sprague (603) 224-1961 (603) 224-1430 part MAX4223EVKIT-so -40? to +85? temp. range board type surface mount in, out 2 sma connectors u1 1 max4223esa ju1 1 3-pin header none 1 shunt for ju1 none 1 pc board none 1 max4223 data sheet note: please indicate that you are using the max4223 when contacting these component suppliers. note: to evaluate the max4224, request a max4224esa free sample. for free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800. for small orders, phone 408-737-7600 ext. 3468.
_______________ detailed description shutdown control the max4223 provides a shutdown pin ( shdn ) to enable or disable the output. table 1 lists the options available for the shutdown control jumper, ju1. to use an external controller, remove the shunt on ju1 com - pletely and connect the external controller to the pad labeled shdn . shdn is a ttl/cmos logic-level input. table 1. jumper ju1 functions voltage gain adjustment the max4223 is optimized for applications requiring a gain of +1 (0db) or greater. its gain can be set by changing the feedback (r f ) and gain-set (r g ) resis - tors. for improved performance at a gain of +2 (6db) or greater, replace the max4223 with a free sample of the max4224. refer to the max4223?ax4228 data sheet for recommended feedback-resistor values. layout considerations the pc board layout has been optimized for high- speed signals and low distortion, with careful attention given to grounding, power-supply bypassing, and sig - nal-path layout. the small, surface-mount, ceramic bypass capacitors (c1 and c2) have been placed as close to the amplifier? supply pins as possible. the ground plane has been removed around and under the amplifier to reduce stray capacitance. capacitance at the inverting input pins has been minimized by reduc - ing the length and width of the input and feedback traces, and by using 0805-size surface-mount feed - back and gain-set resistors. evaluates: max4223/max4224 max4223 evaluation kit 2 _______________________________________________________________________________________ shunt location max4223 shdn pin max4223 output 1 & 2 connected to v cc enabled 2 & 3 connected to gnd disabled max4223 n.c. 1 2 3 in vee 4 shdn 8 3 ju1 r1 49.9 w 2 1 7 6 5 v cc out vcc c4 10 m f 10v c2 0.1 m f shdn out in- r g open in+ r f 560 w c3 10 m f 10v c1 0.1 m f r2 49.9 w n.c. v ee figure 1. max4223 ev kit schematic
evaluates: max4223/max4224 max4223 evaluation kit _______________________________________________________________________________________ 3 figure 2. max4223 ev kit component placement guide 1.0" 1.0" figure 3. max4223 ev kit pc board layout?omponent side figure 4. max4223 ev kit pc board layout?older side 1.0"
evaluates: max4223/max4224 max4223 evaluation kit notes 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 1997 maxim integrated products printed usa is a registered trademark of maxim integrated products.
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