general description the max1473 evaluation kit (ev kit) allows for a detailed evaluation of the max1473 superheterodyne receiver. it enables testing of the device? rf perfor- mance and requires no additional support circuitry. the rf input uses a 50 ? matching network and an sma connector for convenient connection to test equipment. the ev kit can also directly interface to the user? embedded design for easy data decoding. the max1473 ev kit comes in two versions: a 315mhz version and a 433.92mhz version. the passive compo- nents are optimized for these frequencies. these com- ponents can easily be changed to work at rf frequen- cies from 300mhz to 450mhz. in addition, the 5kbps data rate received can be adjusted from 0 to 100kbps by changing two more components. for easy implementation into the customer? design, the max1473 ev kit also features a proven pc board lay- out, which can be easily duplicated for quicker time-to- market. the ev kit gerber files are available for down- load at www.maxim-ic.com. features ? proven pc board layout ? proven components parts list ? multiple test points provided on-board ? available in 315mhz or 433.92mhz optimized versions ? adjustable frequency range from 300mhz to 450mhz* ? fully assembled and tested ? can operate as a stand-alone receiver with addition of an antenna evaluates: max1473 max1473 evaluation kit ________________________________________________________________ maxim integrated products 1 19-2960; rev 1; 5/05 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 designation qty description c1, c2 2 0.01? 10% cer am i c cap aci tor s ( 0603) murata grm188r71h103ka01 c3 1 1500pf 10%, 50v x7r ceramic capacitor (0603) murata grm188r71h152ka01 c4 1 0.47? +80% - 20% ceramic capacitor (0603) murata grm188f51c474za01 c5 1 470pf 5% ceramic capacitor (0603) murata grm1885c1h471ja01 c6, c10 2 220p f 5% cer am i c cap aci tor s ( 0603) murata grm1885c1h221ja01 c7, c8, c11 3 100p f 5% cer am i c cap aci tor s ( 0603) murata grm1885c1h101ja01 c9 (315mhz) 1 4p f 0.1p f cer am i c cap aci tor ( 0603) murata grm1885c1h4r0bz01 c9 (433mhz) 1 2.2p f 0.1p f cer am i c cap aci tor ( 0603) murata grm1885c1h2r2bd01 c12, c20 2 0.1? 5% ceramic capacitors (0603) murata grm188r71c104ka01 c13, c16, c18, c19 0 not installed designation qty description c14, c15 2 15pf 5%, 50v ceramic capacitors (0603) murata grm1885c1h150jz01 c17 0 0.01? +80% - 20% ceramic capacitor (0603), not installed murata grm188r71h103ka01 c21 1 0 ? resistor (0603) f_in 0 sma connector edge mount, not installed johnson 142-0701-801 ju1, ju2, ju5, ju6 4 3-pin headers digi-key s1012-36-nd or equivalent ju7 1 2-pin header ju3, ju4 0 not installed ju8 1 shorted ? shunts (ju1) digi-key s9000-nd or equivalent l1 (315mhz) 1 27nh 5% inductor (0603) coilcraft 0603cs-27nxjb part temp range ic package max1473evkit-315 -40? to +85? 28 tssop max1473evkit-433 -40? to +85? 28 tssop *requires component changes
evaluates: max1473 max1473 evaluation kit 2 _______________________________________________________________________________________ quick start the following procedure allows for proper device evalu- ation. required test equipment regulated power supply capable of providing +3.3v rf signal generator capable of delivering from -120dbm to 0dbm of output power at the operating frequency, in addition to am or pulse-modulation capabilities (agilent e4420b or equivalent) optional ammeter for measuring supply current oscilloscope connections and setup this section provides a step-by-step guide to operating the ev kit and testing the device? functionality. do not turn on the dc power or rf signal generator until all connections are made: 1) connect a dc supply set to +3.3v (through an ammeter, if desired) to the vdd and gnd terminals on the ev kit. do not turn on the supply. 2) connect the rf signal generator to the rf_in sma connector. do not turn on the generator output. set the generator for an output frequency of 315mhz (or 433.92mhz) at a power level of -100dbm. set the modulation of the generator to provide a 2khz 100% am-modulated square wave (or a 2khz pulse-modu- lated signal). 3) connect the oscilloscope to test point tp3. 4) turn on the dc supply. the supply current should read approximately 5ma. 5) activate the rf generator? output without modulation. the scope should display a dc voltage that varies from approximately 1.2v to 2.0v as the rf generator amplitude is changed from -115dbm to 0dbm. ( note: at an input amplitude of around -60dbm, this dc voltage will drop suddenly to about 1.5v and then rise again with increasing input amplitude. this is normal; the agc is turning on the lna gain reduc- tion resistor). 6) set the rf generator to -100dbm. activate the rf generator? modulation and set the scope? coupling to ac. the scope now displays a lowpass-filtered square wave at tp3 (filtered analog baseband data). use the rf generator? lf output (modulation out- put) to trigger the oscilloscope. 7) monitor the data_out terminal and verify the pres- ence of a 2khz square wave. component list (continued) designation qty description l1 (433mhz) 1 15nh 5% inductor (0603) coilcraft 0603cs-15nxjb l2 (315mhz) 1 120nh 5% inductor (0603) coilcraft 0603cs-r12xjb l2 (433mhz) 1 56nh 5% inductor (0603) coilcraft 0603cs-56nxjb l3 1 15nh 5% inductor (0603) murata lqg18hn15nj00 mix out 0 s m a co nnector top m ount, not i nstal l ed digi-key j500-nd johnson 142-0701-201 r1 1 5.1k ? resistor (0603), any r2, r4, r6 0 resistor (0603), not installed r3 0 270 ? r esi stor ( 0603) , any, not i nstal l ed r5 1 10k ? resistor (0603), any r7 1 10pf 5%, 50v ceram i c capaci tor (0603) m urata grm 1 885c1h 100jz 01 r8 1 10k ? resistor (0603), any designation qty description r9 1 1000pf 10%, 50v x7r ceramic capacitor (0603) murata grm188r71h102ka01 rf in 1 sma connector top mount digi-key j500-nd johnson 142-0701-201 tp2, tp4?p12 0 not installed vdd, gnd, shdn, data_out, tp3 5 test points mouser 151-203 or equivalent y1 (315mhz) 1 crystal 4.754687mhz hong kong crystal ssl4754687e03fafz8a0 or crystek 016867 y1 (433mhz) 1 crystal 6.6128mhz hong kong crystal ssl6612813e03fafz8a0 or crystek 016868 y2 1 10.7mhz ceramic filter murata sftla10m7fa00-b0 u1 1 max1473eui ? max1473 ev kit pc board
additional evaluation 1) with the modulation still set to am, observe the effect of reducing the rf generator? amplitude on the data_out terminal output. the error in this sliced digital signal increases with reduced rf sig- nal level. the sensitivity is usually defined as the point at which the error in interpreting the data (by the following embedded circuitry) increases beyond a set limit (ber test). 2) with the above settings, a 315mhz-tuned ev kit should display a sensitivity of about -117dbm (0.2% ber) while a 433.92mhz kit displays a sensitivity of about -115dbm (0.2% ber). note: the above sensi- tivity values are given in terms of average peak power is 3db higher. 3) capacitors c5 and c6 are used to set the corner fre- quency of the 2nd-order lowpass sallen-key data fil- ter. the current values were selected for bit rates up to 5kbps. adjusting these values accommodates higher data rates (refer to the max1473 data sheet for more details). layout issues a properly designed pc board is an essential part of any rf/microwave circuit. on high-frequency inputs and outputs, use controlled-impedance lines and keep them as short as possible to minimize losses and radia- tion. at high frequencies, trace lengths that are on the order of /10 or longer can act as antennas. keeping the traces short also reduces parasitic induc- tance. generally, 1in of a pc board trace adds about 20nh of parasitic inductance. the parasitic inductance can have a dramatic effect on the effective inductance. for example, a 0.5in trace connecting a 100nh inductor adds an extra 10nh of inductance or 10%. to reduce the parasitic inductance, use wider traces and a solid ground or power plane below the signal traces. also, use low-inductance connections to ground on all gnd pins, and place decoupling capacitors close to all vdd connections. the ev kit pc board can serve as a reference design for laying out a board using the max1473. all required components have been enclosed in a 1.25in ? 1.25in square, which can be directly ?nserted?into the appli- cation circuit. detailed description power-down control the max1473 can be controlled externally using the shdn connector. the ic draws approximately 1.25? in shutdown mode. jumper ju1 is used to control this mode. the shunt can be placed between pins 2 and 3 for continuous shutdown, or pins 1 and 2 for continuous operation. remove the ju1 shunt for external control. table 1 describes jumper functions. power supply the max1473 can operate from 3.3v or 5v supplies. for 5v operation, remove ju7 before connecting the supply to vdd. for 3.3v operation, connect ju7. if input/output the 10.7mhz if can be monitored with the help of a spectrum analyzer using the mix_out sma connector (not provided). remove the ceramic filter for such a measurement and include r3 (270 ? ) and c17 (0.01?) to match the 330 ? mixer output with the 50 ? spectrum analyzer. jumper ju3 needs to connect pins 1 and 2. it is also possible to use the mix_out sma connector to inject an external if as a means of evaluating the base- band data slicing section. jumper ju3 needs to con- nect pins 2 and 3. f_in external frequency input for applications where the correct frequency crystal is not available, it is possible to directly inject an external frequency through the f_in sma connector (not provid- ed). connect the sma connector to a function genera- tor. the addition of c18 and c19 is necessary (use 0.01? capacitors). agc control jumper ju5 controls whether the agc is enabled. connect pins 2 and 3 to enable the agc. crystal select jumper ju2 controls the crystal divide ratio. connecting pins 1 and 2 sets the divide ratio to 64, while connecting pins 2 and 3 sets the ratio to 32. this determines the frequency of the crystal to be used. image rejection frequency select a unique feature of the max1473 is its ability to vary at which frequency the image rejection is optimized. ju6 allows the selection of three possible frequencies: 315mhz, 375mhz, and 433.92mhz. see table 1 for set- tings. test points and i/o connections additional test points and i/o connectors are provided to monitor the various baseband signals and for exter- nal connections. see tables 2 and 3 for a description. for additional information and a list of application notes, consult the www.maxim-ic.com website. evaluates: max1473 max1473 evaluation kit _______________________________________________________________________________________________________ 3
evaluates: max1473 max1473 evaluation kit 4 _______________________________________________________________________________________ jumper state function ju1 1-2 normal operation ju1 2-3 power-down mode ju1 nc external power-down control ju2 2-3 crystal divide ratio = 32 ju2 1-2 crystal divide ratio = 64 ju3 1-2 mixer output to mix_out ju3 2-3 external if input ju3 nc normal operation ju4 1-2 uses pdout for faster receiver startup ju4 2-3 gnd connection for peak detector filter ju5 1-2 disables agc ju5 2-3 enables agc ju6 1-2 ir centered at 433mhz ju6 2-3 ir centered at 315mhz ju6 nc ir centered at 375mhz ju7 1-2 connect vdd to +3.3v supply ju7 nc connect vdd to +5.0v supply table 1. jumper functions signal description rf_in rf input f_in external reference frequency input mix_out if input/output gnd ground vdd supply input data_out sliced data output shdn external power-down control table 3. i/o connectors table 2. test points figure 1. max1473 ev kit tp description 2 data slicer negative input 3 data filter output 4 peak detector out 5 +3.3v 6 gnd 7 data filter feedback node 8 data out 9 power-down select input 10 vdd 11 agc control 12 crystal select
evaluates: max1473 max1473 evaluation kit _______________________________________________________________________________________ 5 max1473 1 2 3 4 5 6 7 8 9 10 123 11 12 13 14 in gnd out y2 10.7mhz c1 0.01 f +3.3v ju6 +3.3v 2 1 3 15 16 17 18 19 20 21 22 c6 220pf dsn tp2 c4 0.47 f c5 470pf tp7 tp3 r1 5.1k ? r8 10k ? c3 1500pf tp11 3 2 ju5 tp12 +3.3v ju2 1 3 2 +3.3v 1 3 1 2 ju3 r3 open c17 open r4 open mix_out vdd tp10 ju7 vdd c20 0.1 f tp5 +3.3v ju8 short r6 open r9 1000pf 23 24 25 c21 0 ? r7 10pf r5 10k ? 1 2 3 dsn tp4 c13 open r2 open 26 27 28 ju1 ju4 vdd 1 2 3 tp9 shdn tp8 data_out gnd tp6 c10 220pf c8 100pf c11 100pf c9 * l1 * +3.3v c2 0.01 f +3.3v l3 15nh l2 * c7 100pf rf_in c12 0.1 f c18 open +3.3v c14 15pf c16 open y1 * c15 15pf c19 open f_in xtal2 pwrdn pdout dataout v dd5 v dd dsp dffb opp dsn dfo ifin2 ifin1 xt_sel agc_off dv dd dgnd mixout ir_sel agnd mixin2 mixin1 av dd lnaout agnd lnasrc lnain av dd xtal1 u1 * c9 l1 l2 y1 at 315mhz 4pf 27nh 120nh 4.754689mhz at 433.92mhz 2.2pf 15nh 56nh 6.6128mhz figure 2. max1473 ev kit schematic
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. 6 _____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2005 maxim integrated products printed usa is a registered trademark of maxim integrated products, inc. evaluates: max1473 max1473 evaluation kit figure 3. max1473 ev kit component placement guide component side figure 4. max1473 ev kit pc board layout?omponent side figure 5. max1473 ev kit pc board layout?older side
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