_______________________________________________________________ maxim integrated products 1 for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxims website at www.maxim-ic.com. MAX2686/max2688 gps/gnss low-noise amplifiers 19-5456; rev 0; 8/10 typical application circuit general description the MAX2686/max2688 low-noise amplifiers (lnas) are designed for gps l1, galileo, and glonass applica - tions. designed in maxims advanced sige process, the devices achieve high gain and ultra-low-noise figure while maximizing the input-referred 1db compression point and the 3rd-order intercept point. the MAX2686 provides a high gain of 19db. the max2688 supplies 15db of gain while attaining higher linearity. the devices operate from a +1.6v to +3.3v single sup - ply. the optional shutdown feature in the devices reduc - es the supply current to less than 10 f a. the devices are available in a very small, lead-free, rohs-compliant, 0.86mm x 0.86mm x 0.65mm wafer-level package (wlp). applications automotive navigation telematics (asset tracking and management) personal navigation devices (pnds) cellular phones with gps notebook pcs/ultra-mobile pcs recreational, marine navigation avionics watches digital cameras features s high-power gain: 19db (MAX2686) s ultra-low-noise figure: 0.75db (MAX2686) s integrated 50 output matching circuit s low supply current: 4.1ma s wide supply voltage range: 1.6v to 3.3v s low bill of materials: one inductor, two capacitors s small footprint: 0.86mm x 0.86mm s thin profile: 0.65mm s 0.4mm-pitch wafer-level package (wlp) ordering information + denotes a lead(pb)-free/rohs-compliant package. t = tape and reel. evaluation kit available MAX2686 max2688 a1 a2 b1 b2 optional shutdown gnd shdn r1 25ki rf output rfout v cc v cc c2 rf input c1 l1 rfin MAX2686 l1 = 6.8nh c1 = 100nf c2 = 10pf l1 = 6.2nh c1 = 100nf c2 = 10pf max2688 part temp range pin-package MAX2686 ews+t -40 n c to +85 n c 4 wlp max2688 ews+t -40 n c to +85 n c 4 wlp datasheet.in
MAX2686/max2688 gps/gnss low-noise amplifiers 2 v cc to gnd .......................................................... -0.3v to +3.6v other pins to gnd ............... -0.3v to (+ operating v cc + 0.3v) maximum rf input power ............................................... +5dbm continuous power dissipation (t a = +70c) 4-bump wlp (derates 9.7mw/c above +70c) ........ 776mw maximum current into rf input ......................................... 10ma operating temperature range .......................... -40c to +85c junction temperature ..................................................... +150c storage temperature range ............................ -65c to +160c lead temperature (soldering, 10s) ........ reflow profile (note 1) soldering temperature (reflow) ...................................... +260c dc electrical characteristics (MAX2686/max2688 ev kit, v cc = 1.6v to 3.3v, t a = -40 n c to +85 n c, no rf signals are applied. typical values are at v cc = 2.85v and t a = +25 n c, unless otherwise noted.) (note 2) ac electrical characteristics (MAX2686/max2688 ev kit, v cc = 1.6v to 3.3v, t a = -40 n c to +85 n c, f rfin = 1575.42mhz . typical values are at v cc = 2.85v and t a = +25 n c, unless otherwise noted.) (note 2) absolute maximum ratings note 1: refer to application note 1891: wafer-level packaging (wlp) and its applications . caution! esd sensitive device stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. these are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. parameter conditions min typ max units supply voltage 1.6 2.85 3.3 v supply current shdn = high MAX2686 4.1 ma max2688 4.1 shutdown mode, shdn = low 10 a digital input logic-high (note 3) 1.2 v digital input logic-low (note 3) 0.45 v parameter conditions min typ max units rf frequency l1 band 1575.42 mhz power gain v cc = 2.85v (note 4) MAX2686 14.7 19 db max2688 11.9 15.4 v cc = 1.6v MAX2686 14.4 18.9 max2688 11.6 15.3 noise figure v cc = 1.6v to 3.3v MAX2686 0.75 db max2688 0.8 in-band 3rd-order input intercept point (note 5) MAX2686 -3 dbm max2688 +4 out-of-band 3rd-order input intercept point (note 6) MAX2686 0 dbm max2688 +7 input 1db compression point (note 7) MAX2686 -10 dbm max2688 -6 input return loss 8.5 db datasheet.in
MAX2686/max2688 gps/gnss low-noise amplifiers 3 ac electrical characteristics (continued) (MAX2686/max2688 ev kit, v cc = 1.6v to 3.3v, t a = -40 n c to +85 n c, f rfin = 1575.42mhz . typical values are at v cc = 2.85v and t a = +25 n c, unless otherwise noted.) (note 2) note 2: min and max limits guaranteed by test at t a = +25c and guaranteed by design and characterization at t a = -40c and t a = +85c, unless otherwise noted. note 3: min and max limits guaranteed by test at t a = +25c. note 4: min limit guaranteed by design and characterization. note 5: measured with the two tones located at 1mhz and 2mhz offset from the center of the gps band with -27dbm/tone for the MAX2686 and -24dbm/tone for the max2688. note 6: measured with input tones at 1713mhz (-27dbm) and 1851mhz (-39dbm). note 7: measured with a tone located at 5mhz offset from the center of the gps band. typical operating characteristics (MAX2686/max2688 ev kit. typical values are at v cc = 2.85v, t a = +25c, and f rfin = 1575.42mhz, unless otherwise noted.) input return loss vs. frequency MAX2686 toc01 frequency (mhz) |s11| (db) 2000 1500 1000 -35 -30 -25 -20 -15 -10 -5 0 -40 500 2500 max2688 MAX2686 gain vs. frequency MAX2686 toc02 frequency (mhz) gain (db) 2000 1500 1000 0 5 10 15 20 25 -5 500 2500 MAX2686 max2688 reverse isolation vs. frequency MAX2686 toc03 frequency (mhz) |s12| (db) 2000 1500 1000 -65 -60 -55 -50 -45 -40 -35 -30 -25 -20 -70 500 2500 MAX2686 max2688 output return loss vs. frequency MAX2686 toc04 frequency (mhz) |s22| (db) 2000 1500 1000 -30 -25 -20 -15 -10 -5 0 -35 500 2500 MAX2686 max2688 MAX2686 in-band iip3 vs. supply voltage and temperature (two tones located at 1mhz and 2mhz offset with -30dbm/tone) MAX2686 toc05 supply voltage (v) iip3 (dbm) 3.2 3.0 2.8 2.6 2.4 2.2 2.0 1.8 -5 -4 -3 -2 -1 0 -6 1.6 t a = +85c t a = -40c t a = +25c parameter conditions min typ max units output return loss 15 db reverse isolation 40 db datasheet.in
MAX2686/max2688 gps/gnss low-noise amplifiers 4 typical operating characteristics (continued) (MAX2686/max2688 ev kit. typical values are at v cc = 2.85v, t a = +25c, and f rfin = 1575.42mhz, unless otherwise noted.) max2688 in-band iip3 vs. supply voltage and temperature (two tones located at 1mhz and 2mhz offset with -30dbm/tone) MAX2686 toc06 supply voltage (v) iip3 (dbm) 3.2 3.0 2.8 2.6 2.4 2.2 2.0 1.8 1 2 3 4 5 6 0 1.6 t a = +85c t a = -40c t a = +25c MAX2686 out-of-band iip3 vs. supply voltage and temperature (tone 1 at 1713mhz, -27dbm; tone 2 at 1851mhz, -39dbm) MAX2686 toc07 supply voltage (v) iip3 (dbm) 3.2 3.0 2.6 2.8 2.0 2.2 2.4 1.8 -2.5 -2.0 -1.5 -1.0 -0.5 0 0.5 1.0 1.5 2.0 -3.0 1.6 t a = +85c t a = -40c t a = +25c max2688 out-of-band iip3 vs. supply voltage and temperature (tone 1 at 1713mhz, -27dbm; tone 2 at 1851mhz, -39dbm) MAX2686 toc08 supply voltage (v) iip3 (dbm) 3.2 3.0 2.8 2.6 2.4 2.2 2.0 1.8 2 4 6 8 10 12 0 1.6 t a = -40c t a = +25c t a = +85c MAX2686 input p1db compression vs. supply voltage and temperature MAX2686 toc09 supply voltage (v) input p1db (dbm) 3.2 3.0 2.6 2.8 2.0 2.2 2.4 1.8 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -16 1.6 t a = +85c t a = -40c t a = +25c max2688 input p1db compression vs. supply voltage and temperature MAX2686 toc10 supply voltage (v) input p1db (dbm) 3.2 3.0 1.8 2.0 2.2 2.6 2.4 2.8 -11 -10 -9 -8 -7 -6 -5 -4 -12 1.6 t a = +85c t a = +25c t a = -40c 1db gain desense vs. blocker frequency MAX2686 toc11 blocker frequency (mhz) blocker power (dbm) 2000 1500 1000 -20 -15 -10 -5 0 5 -25 500 2500 max2688 MAX2686 datasheet.in
MAX2686/max2688 gps/gnss low-noise amplifiers 5 bump description bump configuration detailed description the MAX2686/max2688 are lnas designed for gps l1, galileo, and glonass applications. the devices feature an optional power-shutdown control mode to eliminate the need for an external supply switch. the devices achieve high gain, ultra-low-noise figure, and excellent linearity. input and output matching the devices require an off-chip input matching. only an inductor in series with a dc-blocking capacitor is needed to form the input matching circuit. the typical application circuit shows the recommended input- matching network. these values are optimized for the best simultaneous gain, noise figure, and return loss performance. the value of the input coupling capacitor affects iip3. a smaller coupling capacitor results in lower iip3. the devices integrate an on-chip output matching to 50 i at the output, eliminating the need for external matching components. tables 1 and 2 list typical device s parameters and k f values. typical noise parameters are shown in tables 3 and 4. shutdown the devices include an optional shutdown feature to turn off the entire chip. the devices are placed in active mode by default once v cc is applied, due to the on-chip pullup resistor to v cc at the rfout bump (shared with the shdn input). to shut down the part, apply a logic- low to the rfout bump through an external resistor with an adequate value, e.g., 25k i , in order not to load the rf output signal during active operation. wlp top view MAX2686 max2688 rfin v cc gnd rfout (shdn) a1 a2 b1 b2 + bump name function a1 v cc supply voltage. bypass to ground with a 10pf capacitor as close as possible to the ic. a2 rfout ( shdn ) rf output/ shdn input. rfout is internally matched to 50 i and pulled up to v cc through a 1m i resistor. shdn is shared with the rfout bump. the devices are in active mode by default once v cc is applied. rfout( shdn ) can be pulled to a dc low externally to shut down the ic. b1 rfin rf input. requires a dc-blocking capacitor and external matching components. b2 gnd ground. connect to the pcb ground plane. datasheet.in
MAX2686/max2688 gps/gnss low-noise amplifiers 6 table 1. MAX2686 typical s parameter values and k-factor table 3. MAX2686 typical noise parameters (v cc = 2.85v, t a = +25 n c) table 2. max2688 typical s parameter values and k-factor freq. (mhz) s11 mag (db) s11 phase (degrees) s21 mag (db) s21 phase (degrees) s12 mag (db) s12 phase (degrees) s22 mag (db) s22 phase (degrees) k f 1000 -2.9 -26.8 6.2 -109.0 -53.0 169.0 -1.4 -57.0 15.2 1100 -3.1 -27.2 7.9 -110.0 -53.0 163.0 -2.0 -64.0 17.4 1200 -3.4 -27.0 9.5 -113.0 -52.0 157.0 -2.9 -73.0 18.0 1300 -3.5 -28.0 12.8 -128.0 -58.0 -176.0 -7.0 -99.0 40.6 1400 -3.5 -28.3 12.8 -128.0 -56.0 -164.0 -7.0 -99.0 32.3 1500 -3.9 -29.0 13.9 -144.0 -49.0 -166.0 -14.1 -124.0 16.3 1575 -4.1 -27.0 14.1 -156.0 -47.0 164.0 -29.0 -113.0 13.5 1600 -4.1 -27.7 14.1 -160.0 -48.0 154.0 -21.2 68.0 15.0 1700 -4.0 -28.1 13.9 -174.0 -54.0 166.0 -9.0 42.0 26.4 1800 -4.2 -28.9 12.9 170.0 -49.0 -160.0 -5.3 26.4 13.6 1900 -4.4 -29.0 11.4 160.0 -47.3 -176.0 -3.3 13.9 10.2 2000 -4.5 -28.9 9.9 153.0 -46.5 170.0 -2.3 5.0 8.5 freq. (mhz) s11 mag (db) s11 phase (degrees) s21 mag (db) s21 phase (degrees) s12 mag (db) s12 phase (degrees) s22 mag (db) s22 phase (degrees) k f 1000 -3.2 -18.0 3.6 -116.0 -54.0 150.0 -1.3 -53.0 22.5 1100 -3.4 -17.5 5.2 -116.9 -55.0 147.0 -1.9 -60.6 29.9 1200 -3.6 -16.8 6.8 -119.0 -56.6 147.0 -2.7 -69.2 40.5 1300 -3.5 -17.2 8.6 -124.0 -63.0 -144.0 -4.2 -80.0 90.4 1400 -3.8 -18.0 10.1 -137.5 -49.8 -145.0 -7.7 -95.0 23.7 1500 -4.0 -16.5 10.7 -151.0 -47.3 174.0 -14.5 -107.7 19.7 1575 -4.1 -15.8 11.0 -161.5 -48.3 169.0 -35.0 151.0 22.4 1600 -4.1 -15.7 11.1 -164.9 -48.7 159.0 -23.4 74.9 23.1 1700 -4.1 -16.6 11.0 -179.0 -55.0 175.0 -9.7 50.0 43.1 1800 -4.2 -16.7 10.2 165.0 -48.0 -151.0 -5.2 34.0 16.5 1900 -4.4 -16.6 8.6 155.0 -46.0 -164.0 -3.2 21.0 11.9 2000 -4.5 -16.3 7.2 149.0 -45.6 -179.0 -2.3 12.0 10.6 frequency (mhz) fmin (db) | g opt | | g opt | angle r n ( i ) 1550 0.63 0.43 45.7 8.25 1560 0.63 0.43 46.0 8.23 1570 0.63 0.42 46.3 8.22 1575 0.63 0.42 46.4 8.22 1580 0.63 0.42 46.5 8.21 1590 0.63 0.42 46.8 8.20 1600 0.64 0.42 47.1 8.19 datasheet.in
MAX2686/max2688 gps/gnss low-noise amplifiers 7 applications information a properly designed pcb is essential to any rf micro - wave circuit. use controlled-impedance lines on all high-frequency inputs and outputs. bypass v cc with decoupling capacitors located close to the device. for long v cc lines, it may be necessary to add decoupling capacitors. locate these additional capacitors further away from the device package. proper grounding of the gnd pin is essential. if the pcb uses a topside rf ground, connect it directly to the gnd pin. for a board where the ground is not on the component layer, connect the gnd pin to the board with multiple vias close to the package. refer to www.maxim-ic.com for the MAX2686 ev kit schematic, gerber data, pads layout file, and bom information. chip information process: sige bicmos package information for the latest package outline information and land patterns, go to www.maxim-ic.com/packages . note that a +, #, or - in the package code indicates rohs status only. package drawings may show a different suffix character, but the drawing pertains to the package regardless of rohs status. table 4. max2688 typical noise parameters (v cc = 2.85v, t a = +25 n c) frequency (mhz) fmin (db) | g opt | | g opt | angle r n ( i ) 1550 0.73 0.42 59.0 8.34 1560 0.74 0.42 59.4 8.31 1570 0.74 0.42 59.7 8.29 1575 0.74 0.42 59.9 8.28 1580 0.74 0.42 60.1 8.27 1590 0.74 0.41 60.5 8.25 1600 0.74 0.41 60.8 8.22 package type package code outline no. land pattern no. 4 wlp w40a0+1 21-0480 datasheet.in
maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circuit patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. 8 maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 ? 2010 maxim integrated products maxim is a registered trademark of maxim integrated products, inc. MAX2686/max2688 gps/gnss low-noise amplifiers revision history revision number revision date description pages changed 0 8/10 initial release datasheet.in
|
