general description the max2820/max2821 evaluation kits (ev kits) simplify testing of the max2820/max2821. the ev kits provide 50 ? sma connectors for all rf and baseband inputs and outputs. differential-to-single-ended and single-ended-to- differential line drivers are provided to convert the differ- ential i/q baseband inputs and outputs to single ended. the ev kits simplify evaluation of the max2820/ max2821s?receive and transmit performance in 802.11b applications operating in the 2.4ghz to 2.5ghz ism band. features ? on-board line drivers and voltage reference ? 50 ? sma connectors on all rf and baseband ports ? pc control software available at www.maxim-ic.com ? spi /qspi /microwire compatible evaluate: max2820/max2821 max2820/max2821 evaluation kits ________________________________________________________________ maxim integrated products 1 19-2581; rev 0; 9/02 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 spi and qspi are trademarks of motorola, inc. microwire is a trademark of national semiconductor corp. part temp range ic package max2820evkit -40 c to +85 c 48 qfn MAX2821EVKIT -40 c to +85 c 48 qfn designation qty description c1, c3, c7, c10?16, c20?23, c25, c26, c28, c29, c33, c34, c35, c40, c50, c51 24 0.01? 10% ceramic capacitors (0402) murata grp155r71c103k c2, c4, c5, c6, c8, c9, c17, c18, c19, c27, c36?39, c41?45 19 0.1? 10% capacitors (0402) murata grp155r61a104k c24, c46, c47, c48 4 10? 10%, 16v tantalum capacitors, c case avx tajc106k016 c30 1 82pf 5% capacitor (0402) murata grp1555c1h820j c31 1 100pf 5% capacitor (0402) murata grp1555c1h101j c32 1 2000pf 10% capacitor (0402) murata grp155r71h202k c49 1 20pf 5% capacitor (0402) murata grp1555c1h200j c52 1 8200pf 10% capacitor (0402) murata grp155r71e822k c53, c54 2 10pf 0.1pf capacitors (0402) murata grp1555c1h100b c55, c56 2 not installed j1, j2, j5, j6, j13, j14, j17 7 sma connectors, edge mount efjohnson 142-0701-801 digi-key j502-nd designation qty description j3, j4, j7, j8, j11, j12, j15, j16 8 not installed j9, j10, j18?22 7 test points digi-key 5000k-nd j23 1 db25 male connector, right angle amp amp747238-4 digi-key a2098-nd jp1?p5, jp10, jp18?p21 10 not installed l1 1 0 ? 5% resistor (0402) l2, l3 2 6.8nh 5% inductors (0402) murata lqg15hn6n8j02 l4 1 5.6nh 0.3nh inductor (0402) murata lqg15hn5n6s02 r1, r2 2 10k ? 10% variable resistors trimmer?bourne 3296w-103 potentiometer digi-key 3296w-103- nd r3, r4, r35 3 100 ? 1% resistors (0402) r5, r7, r13, r17, r21, r22, r29, r31 875 ? 1% resistors (0402) r6, r10, r16, r18, r19, r24, r26, r32, r34, r41, r42, r48, r49 13 0 ? 5% resistors (0402) r8, r14, r23, r30 4 10k ? 1% resistors (0402)
evaluate: max2820/max2821 max2820/max2821 evaluation kits 2 _______________________________________________________________________________________ quick start the max2820/max2821 ev kits are fully assembled and factory tested. follow the instructions in the connections and setup section. test equipment required this section lists the recommended test equipment to ver- ify the operation of the max2820/max2821. it is intended as a guide only, and substitutions may be possible. dc supply capable of delivering +5.0v and 200ma of continuous current dc supply capable of delivering -5.0v and 200ma of continuous current dc supply capable of delivering +2.7v and 200ma of continuous current hp8663a or equivalent low-noise signal source capable of generating a 22mhz or 44mhz refer- ence oscillator signal two hp8648 or equivalent signal sources capable of generating 0dbm up to 3ghz 802.11b waveform generator hp8561e or equivalent rf spectrum analyzer with a minimum frequency range of 100khz to 3ghz tds3012 or equivalent oscilloscope with 200mhz bandwidth ibm pc or compatible with windows 95/98 , windows 2000 , windows nt 4.0, or later operat- ing system and an available parallel port male-to-male 25-pin parallel cable, straight through connections and setup this section provides step-by-step instructions for get- ting the ev kit up and running in all modes: 1) to control the max2820/max2821 through the 3-wire interface, connect the male-to-male 25-pin parallel cable between the pc and ev kit. 2) with the power supply turned off, connect a +2.7v power supply to the headers labeled vcc (j19) and vcco (j10). connect the power-supply ground to the header labeled gnd (j18). 3) with the power supply turned off, connect a +5v power supply to the header labeled +5v (j22), and a -5v power supply to the header labeled -5v (j20). connect the power-supply ground to the header labeled gnd (j21). 4) connect the low-noise signal source to rosc (j17). 5) install and run the max2820/max2821 control software. 6) with the max2820/max2821 control software active in the ?ettings?screen, use table 1 to set the oper- ating mode to shutdown. 7) turn on the +5v and -5v power supplies, followed by the +2.7v power supply. 8) set the low-noise signal source to 22mhz with an amplitude of -10dbm. enable the signal source. receive mode to evaluate the max2820/max2821 in receive mode: 1) connect an rf signal source to rx_rf (j2). set the rf frequency to 2437.9mhz with an amplitude of -40dbm. 2) connect rx_bbi (j5) to the spectrum analyzer. set the spectrum analyzer to span from 100khz to 5mhz. 3) place the receive lna in high-gain mode through the control software. designation qty description r9, r15, r25, r33, r36, r43, r44?47, r50?60 21 not installed r11, r12, r20, r27, r28 5 49.9 ? 1% resistors (0402) r37 1 12.1k ? 1% resistor (0402) r38 1 2.43k ? 1% resistor (0402) r39 1 1.82k ? 1% resistor (0402) r40 1 27.4k ? 1% resistor (0402) t1 1 chip hybrid balun murata ldb212g4020c-001 t2 1 chip hybrid balun murata ldb212g4005c-001 tp1?p5, tp7?p11 10 test points digi-key 5000k-nd tp6 1 not installed u1, u5 2 max4447ese u2, u6 2 max4444ese u3 1 max6061beur u4 1 max2820egm/max2821etm u7 1 octal buffer/driver texas instruments sn74lvth244adbr digi-key 296-1269-1-nd u8 1 not installed component list (continued) windows 95/98, windows 2000, and windows nt are registered trademarks of microsoft, inc.
evaluate: max2820/max2821 max2820/max2821 evaluation kits _______________________________________________________________________________________ 3 supplier phone fax website avx 843-448-9411 843-448-1943 www.avx.com digi-key 800-344-4539 218-681-3380 www.digikey.com murata 770-436-1300 770-436-3030 www.murata.com texas instruments www.ti.com component suppliers control modes shutdown device in shutdown mode standby device in standby mode transmit device in transmit mode operating mode receive device in receive mode high gain receive lna in high-gain mode lna gain low gain receive lna in low-gain mode enable sets receive highpass corner frequency to 1khz rx_1k disable sets receive highpass corner frequency to 10khz program modes lo frequency variable sets lo frequency from 2400mhz to 2499mhz 22mhz sets pll to work with 22mhz crystal oscillator ref frequency 44mhz sets pll to work with 44mhz crystal oscillator cp current variable sets charge-pump current between 1ma and 2ma power amp bias variable sets external power amplifier bias current receive lpf bw variable sets receive lowpass corner frequency from 6.0mhz to 8.5mhz table 1. max2820/max2821 control settings 4) verify that the lo frequency is set to 2437mhz through the control software. 5) set the operating mode to ?eceive?through the control software. 6) measure the power of the 900khz output tone on the spectrum analyzer display. adjust rx_agc (r2) between 0v and 2.0v to obtain a baseband output of -2dbm. transmit mode to evaluate the max2820/max2821 in transmit mode: 1) connect a signal source to tx_bbi (j6). set the sig- nal source frequency to 900khz with an amplitude of 400mv p-p (-4dbm). 2) connect tx_rf (j1) to the spectrum analyzer. set the spectrum analyzer to a center frequency of 2437mhz with a 20mhz span. 3) verify that the lo frequency is set to 2437mhz through the control software. 4) temporarily disable the baseband signal source output. set the operating mode to ?ransmit through the control software. enable the baseband signal source output. 5) measure the amplitude of the upper sideband at 2437.9mhz using the spectrum analyzer. adjust tx_gc (r1) to 0v to obtain the maximum rf output. 6) the observed output power should be roughly -5dbm due to driving only the i channel. layout considerations the max2820/max2821 ev kits can serve as guides for board layout. keep pc board trace lengths as short as possible to minimize parasitic inductance. also, keep decoupling capacitors as close to the ic as pos- sible with a direct connection to the ground plane.
evaluate: max2820/max2821 max2820/max2821 evaluation kits 4 _______________________________________________________________________________________ figure 1. max2820/max2821 ev kits schematic
evaluate: max2820/max2821 max2820/max2821 evaluation kits _______________________________________________________________________________________ 5 figure 2. max2820/max2821 ev kits pc board layout?op silkscreen 1.0"
figure 3. max2820/max2821 ev kits pc board layout component side figure 4. max2820/max2821 ev kits pc board layout?nner layer 2 figure 5. max2820/max2821 ev kits pc board layout?nner layer 3 figure 6. max2820/max2821 ev kits pc board layout solder side 1.0" 1.0" 1.0" 1.0" evaluate: max2820/max2821 max2820/max2821 evaluation kits 6 _______________________________________________________________________________________
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 _____________________ 7 2002 maxim integrated products printed usa is a registered trademark of maxim integrated products. evaluate: max2820/max2821 max2820/max2821 evaluation kits figure 7. max2820/max2821 ev kits pc board layout?ottom silkscreen 1.0"
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