general description the max2015 evaluation kit (ev kit) is a fully assembled and tested surface-mount circuit board that allows for easy evaluation of the max2015 rf power detector/ controller. the max2015 ev kit includes connections to operate the device as a detector or as a controller. the rf input utilizes a 50 ? sma connector for convenient connection to test equipment. features ? complete rf power detector/controller ? 50mhz to 2.7ghz frequency range ? 2.7v to 5.25v single-supply operation* ? 50 ? sma connector on rf input ? fully assembled and tested surface-mount board * see ev kit schematic (figure 3). evaluates: max2015 max2015 evaluation kit ________________________________________________________________ maxim integrated products 1 19-3083; rev 0; 12/03 component list 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 component suppliers designation qty description c1, c2 2 680pf ?%, 50v c0g ceramic capacitors (0603) murata grm1885c1h681j c3, c5 2 100pf ?%, 50v c0g ceramic capacitors (0603) murata grm1885c1h101j c4, c6 2 0.1? ?0%, 16v x7r ceramic capacitors (0603) murata grm188r71c104k c7 1 10? ?0%,16v tantalum capacitor (c case) avx tajc106k016r c8 0 not installed (0603) j1?4 4 pc board edge-mount sma rf connectors (flat-tab launch) johnson 142-0741-856 r1?5 5 0 ? (0603) resistors r6, r7 0 not installed (0603) tp1 1 large test point for 0.062in pc board (red) mouser 151-107 or equivalent tp2 1 large test point for 0.062in pc board (black) mouser 151-103 or equivalent u1 1 max2015eua-t part temp range ic package MAX2015EVKIT -40? to +85? 8 ?ax quick start the max2015 ev kit is fully assembled and factory tested. see the connections and setup section for proper device evaluation. recommended equipment dc power supply capable of delivering between 2.7v and 3.6v at 25ma signal generator capable of delivering -70dbm to +10dbm at frequencies between 50mhz and 2.7ghz high-dynamic-range rf power meter for calibrat- ing the signal generator three digital multimeters (dmms) to monitor sup- ply voltage, supply current, and output voltage 6db attenuator pad procedure this section provides a step-by-step guide to testing the basic functionality of the ev kit. as a general precaution to prevent damaging the device, do not turn on the dc power or the rf signal generator until all connec- tions are made: 1) with the dc power supply disabled, set it to +3.3v (through a low internal resistance ammeter, if desired) and connect to the vcc terminal. connect the power-supply ground to the gnd terminal on the ev kit. if available, set the current limit to 25ma. 2) calibrate the power meter at 100mhz. 3) connect the rf signal generator to the power meter through a 6db attenuator pad. supplier phone website johnson 507-833-8822 www.johnsoncomponents.com murata 770-436-1300 www.murata.com
evaluates: max2015 4) calibrate the signal generator output (f = 100mhz) over the desired power range. note: some power meters may be limited in terms of their dynamic range. 5) disable the rf signal generator output power. disconnect the power meter from the attenuator pad and connect this pad output to the rf_in sma on the ev kit. 6) connect the vout sma to a voltmeter through the appropriate adapters. enable the dc power sup- ply. the dc current of the ev kit should be approximately 17ma. 7) enable the output power of the rf signal generator. 8) using the calibration results from step 4, set the generator output at the level that produces -30dbm into rf_in. 9) verify that an output voltage of approximately 1.35v is measured on the voltmeter. 10) adjust the signal-generator power level up and down to see a corresponding change in vout. detailed description the max2015 ev kit is a fully assembled and tested sur- face-mount circuit board that evaluates the max2015 rf power detector/controller. the rf input utilizes a 50 ? sma connector for convenient connection to test equipment. detector mode the max2015 ev kit is assembled with a 0 ? resistor for r1. this sets the slope of the output signal to approxi- mately 19mv/db (rf = 100mhz). to increase the slope of the output signal, increase the value of r1. for example, if a 4.7k ? resistor is used, the slope increases to approxi- mately 21.7mv/db. setting the slope too high causes the output of the log amp to be voltage limited at high rf power levels, thus reducing dynamic range. for more information, refer to the applications information section in the max2015 data sheet. max2015 evaluation kit 2 _______________________________________________________________________________________ max2015 ev kit 6db j3 sma vset j2 sma vout j4 sma pwdn j1 sma rf_in tp2 gnd tp1 vcc (voltmeter) (voltmeter) (ammeter) 17.0ma 3.30vdc 3.30vdc 1.35vdc 100mhz -24dbm figure 1. max2015 ev kit test setup diagram
controller mode for operation in controller mode, remove r1 and set r6 to 0 ? . use a dac or external precision voltage supply to apply the set-point voltage to the vset sma connector. rf_in is connected to the rf source (power amplifier (pa) output through a directional coupler) and vout is connected to the gain-control pin of the pa (see figure 2 ) . shutdown mode the ev kit is configured with the shutdown feature dis- abled. to use the shutdown feature first remove r5. drive pwdn with a logic-low (0v) for normal operation or a logic-high (vcc) to place the device in shutdown mode. leave the vcc power supply on and turn off the rf power when switching the shutdown pin. layout considerations a good pc board is an essential part of rf circuit design. the max2015 ev kit pc board can serve as a guide for laying out a board using the max2015. keep the input trace carrying rf signals as short as possible to minimize radiation and insertion loss due to the pc board. each power-supply node on the pc board should have its own decoupling capacitor. this mini- mizes supply coupling from one section of the pc board to another. using a star topology for the supply layout, in which each power-supply node in the circuit has a separate connection to the central node, can further minimize coupling between sections of the pc board. modifying the ev kit the ev kit design includes some additional resistors (r2, r3, r4) to provide for possible power-supply filtering and for high power-supply voltage operation. for operation where v cc = 2.7v to 3.6v (tp1), set r4 = 0 ? . for opera- tion where v cc = 4.75v to 5.25v, set r4 = 75 ? ?% (100ppm/? max) and connect pwdn to gnd (required). the output load for vout can be changed by including the values for r7 and c8. evaluates: max2015 max2015 evaluation kit _______________________________________________________________________________________ 3 max2015 logarithmic detector transmitter set-point dac 20k ? 20k ? out set in power amplifier coupler gain-control input figure 2. max2015 in controller mode c6 c5 v r2 c4 c3 v r3 c1 c2 v cc inlo inhi v cc 4 3 2 1 5 6 7 8 pwdn gnd set out max2015 r1 r7 r6 c8 r5 j4 sma pwdn j3 sma vset j2 sma vout c7 r4 v tp2 gnd tp1 v cc * j1 sma rf_in *v cc = 2.7v to 3.6v with r4 = 0 ? v cc = 4.75v to 5.25v with r4 = 75 ? figure 3. max2015 ev kit schematic
evaluates: max2015 max2015 evaluation kit 4 _______________________________________________________________________________________ figure 4. max2015 ev kit pc board layout?op silkscreen figure 5. max2015 ev kit pc board layout?op solder mask figure 6. max2015 ev kit pc board layout?op layer metal figure 7. max2015 ev kit pc board layout?nner layer 2 (gnd)
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: max2015 max2015 evaluation kit figure 8. max2015 ev kit pc board layout?nner layer 3 (routes) figure 9. max2015 ev kit pc board layout?ottom layer metal figure 10. max2015 ev kit pc board layout?ottom solder mask figure 11. max2015 ev kit pc board layout?ottom silkscreen
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