general description the max2247 evaluation kit (ev kit) simplifies evalua- tion of the max2247 power amplifier (pa). the kit enables testing of the device? rf performance and requires no additional support circuitry. the ev kit input and output use sma connectors to facilitate the con- nection to rf test equipment. each kit is assembled with the max2247 and incorpo- rates all matching components optimized for the 2.4ghz to 2.5ghz rf frequency band, and p out = +24dbm. for lower power applications, see table 2 for appropriate matching components. features easy evaluation of max2247 +2.7v to +3.6v single-supply operation output matched for 2.4ghz to 2.5ghz operation fully assembled and tested quick start the max2247 ev kit is fully assembled and factory test- ed. follow the instructions in the connections and setup section for proper device evaluation. test equipment required table 1 lists the required test equipment to verify max2247 operation. it is intended as a guide only, and some substitutions are possible. connections and setup this section provides a step-by-step guide to operating the ev kit and testing the device? functions. do not turn on dc power or rf signal generators until all connec- tions are made. testing the supply current 1) connect a 20db attenuator to the out sma con- nector on the ev kit. this prevents overloading of the power sensor and power meter. 2) connect a dc supply set to +3.3v (through an amme- ter, if desired) and connect a voltmeter to the ev kit? vcc and gnd terminals. do not turn on the supply. 3) connect an rf signal generator to the in sma con- nector. calibrate the generator to produce an 802.11b compatible -10dbm signal, at 2.45ghz output frequency. do not turn on the output. 4) connect the power sensor to the power meter. calibrate the power sensor for 2.45ghz. set the power meter offset to compensate the 20db attenua- tor, the coupler, and any cable loss (from 0.5db to 2db), and circuit board losses (approximately 0.3db). evaluates: max2247 max2247 evaluation kit ________________________________________________________________ maxim integrated products 1 designation qty description c1, c8, c10, c12, c32 5 22pf ceramic capacitors (0402) grp1555c1h220j c2, c6, c7, c9 4 10nf ceramic capacitors (0402) grp155r71c103k c3 1 2.7pf ceramic capacitor (0402) grp1555c1h2r7b c4, c5 2 47pf ceramic capacitors (0402) grp1555c1h470j c11 1 4.7f tantalum capacitor jmk212bj475mg-b c31 open c33 1 0.75pf ceramic capacitor (0402) gj61555c1hr75b l1 1 3.9nh inductor (0402) ll1005_fh3n95 r1 1 3k ? 5% resistor r2 1 7.5k ? 5% resistor r8 1 51k ? 5% resistor component list 19-2591; rev 0; 9/02 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. part temp range ic package MAX2247EVKIT -40 c to +85 c3 ? 4 ucsp supplier phone fax efjohnson 402-474-4800 402-474-4858 kamaya 260-489-1533 260-489-2261 murata 800-831-9172 814-238-0490 taiyo yuden 800-348-2496 408-434-0375 toko 800-715-8656 408-943-9790 component suppliers ordering information
evaluates: max2247 5) connect the power sensor to the coupler. connect one of the remaining terminals of the coupler to the 20db high-power attenuator and another end to the spectrum analyzer. 6) place the shdn jumper in the on position. 7) turn on the dc supply. the idle current should read approximately 250ma. 8) activate the rf generator output. set the rf gener- ator s output to produce a reading of +23dbm on the power meter. adjust the supply voltage so that the voltmeter reads +3.3v. adjust the output of the generator until the power meter reads +24dbm. the supply current should increase to approxi- mately 315ma. the acpr/alt measurements should meet the max2247 ec table specifications. lower power applications this evaluation kit can be easily modified for p out = +21dbm, +18dbm, and +15dbm applications by changing the position of c3 and the bias current and removing c33. (see table 2 and applications notes.) layout the ev kit s pc board can serve as a guide for laying out a board using the max2247. keep rf signal lines as short as possible to minimize losses and radiation. always use controlled impedance lines on all high-frequency inputs and outputs, and use low-inductance connections to ground on all gnd pins. each v cc node on the pc board should have its own decoupling capacitor. using a star topology for the supply layout, in which each v cc _ node on the circuit has a separate connection to a central v cc node, can further minimize coupling between the sections of the ic. (refer to the max2247 data sheet.) max2247 evaluation kit 2 _______________________________________________________________________________________ equipment qty description power supply 1 capable of delivering up to 500ma at +2.7v to +3.6v rf signal generator 1 capable of delivering +10dbm of output power up to 2.5ghz with 802.11b-compatible source rf power sensor 1 capable of handling +20dbm of output power at the operating frequency (hp 8482a, or equivalent) 20db high-power attenuator 1 power meter 1 capable of handling +20dbm of output power at the operating frequency (hp epm-441a, or equivalent) coupler 1 capable of operating at the desired frequency rf spectrum analyzer 1 capable of measuring acpr/alt and covering the max2247 s operating frequency range (rohde and schwarz fsea20, or equivalent) ammeter/voltmeter 2 50 ? sma cables 2 network analyzer (optional) 1 for measuring small-signal return loss and gain table 1. test equipment required table 2. ev kit modifications for p out = +21dbm, +18dbm, and +15dbm applications p out (dbm) c3 location r1 (i bias ) +21 7 6.1k ? (135ma) +18 6 12k ? (75ma) +15 6 13k ? (65ma)
evaluates: max2247 max2247 evaluation kit _______________________________________________________________________________________ 3 figure 1. max2247 ev kit schematic figure 2. max2247 ev kit component placement guide primary-side silkscreen figure 3. max2247 ev kit component placement guide secondary-side silkscreen 1.0" 1.0"
evaluates: max2247 max2247 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 ? 2002 maxim integrated products printed usa is a registered trademark of maxim integrated products. figure 4. max2247 ev kit pc board layout?ayer 2 figure 5. max2247 ev kit pc board layout?ayer 3 figure 6. max2247 ev kit pc board layout?rimary component side figure 7. max2247 ev kit pc board layout?econdary component side 1.0" 1.0" 1.0" 1.0"
|
