general description the max3558 broadband quad-output low-noise ampli- fier (lna) is designed for digital set tops and digital ter- restrial applications. the lna covers a 50mhz to 878mhz input frequency range, while integrating a sep- arate automatic gain-control (agc) function with over 30db of control range for each of four balanced out- puts. each output has its own shutdown control to reduce power consumption when not used. the max3558 also includes a power detector that can be used to close the loop on any of the agcs to prevent overload conditions. the lna? attack point is adjustable with an external resistor. the max3558 is available in a very small 28-pin qfn package with exposed paddle (ep). applications digital set-top boxes digital terrestrial receivers tuner preamps features ? quad outputs with independent agcs and shutdown ? 50mhz to 878mhz broadband operation ? integrated power detector ? high linearity: 15.6dbm iip3 max3558 quad-output lna with agc for cable tv applications ________________________________________________________________ maxim integrated products 1 1 2 3 4 5 6 7 22 23 24 25 26 27 28 21 20 19 18 17 16 15 8910 11 12 13 14 power detector bias lb rfin+ rfin- v cc v cc pdagc pdout pdref v cc shdn4 agc4 out4- out4+ shdn3 agc3 out3+ out3- agc2 out2- out2+ shdn2 agc1 out1- out1+ v cc exposed paddle is connected to gnd top view shdn1 gnd max3558 pin configuration/functional diagram ordering information 19-3025; rev 0; 11/03 evaluation kit available 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. * ep = exposed paddle. part temp range pin-package MAX3558CGI 0 c to +70 c 28 qfn-ep* (5mm x 5mm)
max3558 quad-output lna with agc for cable tv applications 2 _______________________________________________________________________________________ absolute maximum ratings dc electrical characteristics (v cc = 4.75v to 5.25v, no rf signal applied, r bias = 1.1k ? ? shdn_ _ nd _ _ s d d n caution! esd sensitive device
max3558 quad-output lna with agc for cable tv applications _______________________________________________________________________________________ 3 ac electrical characteristics (v cc = 4.75v to 5.25v, f rfin = 50mhz to 878mhz, 75 ? shdn_ s ? ? noise figure worst case across band, 75 ? 8.4 9.9 db maximum gain -1.1 input p1db compression point 10db gain reduction +1.3 dbm maximum gain, p in = -9dbm 14.4 input 3rd-order intercept point (iip3) (note 3) 10db gain reduction, p in = -9dbm (note 2) 15.6 dbm maximum gain, p in = -9dbm +45.9 input 2nd-order intercept point (iip2) (note 3) 10db gain reduction, p in = -9dbm (note 2) +29.5 dbm input return loss any gain setting 9 db output return loss 75 ? 8 db out_ to rfin isolation 65 db rfin to out_ shutdown isolation vga in shutdown, f rfin = 54mhz to 72mhz 40 db output-to-output isolation between any two outputs 45 db power-detector operating range (per channel) f rfin = 50mhz to 878mhz (note 4) -3 +17 dbmv agc attack range (per channel) r pdref = 800 ? ? -3 +6 dbmv agc attack accuracy (per channel) 130 channel loading (notes 2, 4) -2.2 +2.2 dbmv attack point variation any one output in shutdown mode (note 4) -0.5 +0.5 dbm agc attack slope change of pout_ over 12db change in p rfin after reaching agc attack point (notes 2, 4) -2 +2 db note 1: guaranteed by design and characterization. note 2: guaranteed by production test. note 3: measured with two input tones (f 1 = 800mhz, f 2 = 845mhz). note 4: pdout connected to pdagc and agc_. note 5: p in is single-tone equivalent to 130 channel loading.
supply current vs. supply voltage max3558 toc01 supply voltage (v) supply current (ma) 5.3 5.1 4.7 4.9 210 220 230 240 250 260 270 280 200 4.5 5.5 t a = +70 gain vs. frequency max3558 toc02 frequency (mhz) gain (db) 750 850 550 650 250 350 450 150 1 2 3 4 5 6 7 8 9 10 0 50 v cc_ = 5v v agc_ = 3v t a = 0 gain vs. frequency max3558 toc03 frequency (mhz) gain (db) 750 850 550 650 250 350 450 150 1 2 3 4 5 6 7 8 9 10 0 50 v agc_ = 3v t a = +25 gain vs. frequency max3558 toc04 frequency (mhz) gain (db) 850 750 550 650 250 350 450 150 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 -12 50 v agc_ = 3v v agc_ = 1.97v v agc_ = 1.81v v agc_ = 1.69v v agc_ = 1.59v v agc_ = 1.50v v agc_ = 1.42v v agc_ = 1.35v v agc_ = 1.28v v cc_ = 5v t a = +25 noise figure vs. frequency max3558 toc05 frequency (mhz) noise figure (db) 850 750 650 550 450 350 250 150 2 4 6 8 10 12 0 50 t a = +25 noise figure vs. gain max3558 toc06 gain (db) noise figure (db) 5 0 -20 -15 -10 -5 5 10 15 20 25 30 35 40 0 -25 10 t a = +25 iip3 vs. frequency max3558 toc07 frequency (mhz) iip3 (dbm) 850 750 550 650 250 350 450 150 2 4 6 8 10 12 14 16 18 20 22 0 50 950 t a = +70 iip3 vs. frequency max3558 toc08 frequency (mhz) iip3 (dbm) 850 750 550 650 250 350 450 150 2 4 6 8 10 12 14 16 18 20 22 0 50 950 t a = +70 iip2 vs. frequency max3558 toc09 frequency f a (mhz) iip2 (dbm) 850 750 650 550 450 350 250 150 10 20 30 40 50 60 0 50 t a = +25 shdn_ s ? ?
max3558 quad-output lna with agc for cable tv applications _______________________________________________________________________________________ 5 agc attack point vs. r pdref max3558 toc13 r pdref (k ? port-to-port isolation vs. frequency max3558 toc14 frequency (mhz) isolation (db) 850 750 550 650 250 350 450 150 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 -100 50 v agc_ = 3v t a = +25 output to rfin isolation vs. frequency max3558 toc15 frequency (mhz) isolation (db) 850 750 550 650 250 350 450 150 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 -100 50 v agc_ = 3v t a = +25 rfin to output isolation vs. frequency max3558 toc16 frequency (mhz) isolation (db) 850 750 550 650 250 350 450 150 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 -100 50 v agc_ = 3v t a = +25 input return loss vs. frequency max3558 toc17 frequency (mhz) input return loss (db) 800 600 400 200 -18 -16 -14 -12 -10 -8 -6 -4 -2 0 -20 0 1000 75 ? output return loss vs. frequency max3558 toc18 frequency (mhz) output return loss (db) 800 600 400 200 -18 -16 -14 -12 -10 -8 -6 -4 -2 0 -20 0 1000 75 ? iip2 vs. frequency max3558 toc10 frequency f a (mhz) iip2 (dbm) 850 750 650 550 450 350 250 150 10 20 30 40 50 60 0 50 10db gain reduction f a + f b = 860mhz t a = 0 iip2 vs. frequency max3558 toc11 frequency f a (mhz) iip2 (dbm) 850 750 650 550 450 350 250 150 10 20 30 40 50 60 0 50 950 v agc_ = 3v f a - f b = 50mhz t a = +25 iip2 vs. frequency max3558 toc12 frequency (mhz) iip2 (dbm) 850 750 650 550 450 350 250 150 10 20 30 40 50 60 0 50 950 v agc_ = 1.5v f a - f b = 50mhz 10db gain reduction t a = +70 shdn_ s ? ?
max3558 quad-output lna with agc for cable tv applications 6 _______________________________________________________________________________________ pin description pin name function 1 bias external bias. connect an external 1.1k ? shdn4 s4d44d 1 4 44n4 1112 4 4 dn4d 14 shdn3 s3d33d 11 3 3 dn3d 1 3 33n3 1 nd 1 2 22n2 221 2 2 dn2d 22 shdn2 s2d22d 242 1 1 dn1d 2 1 11n1 2 shdn1 s1d11d ndd
max3558 quad-output lna with agc for cable tv applications _______________________________________________________________________________________ 7 detailed description the max3558 broadband lna consists of a single input and four independent outputs. each output has its own agc and shutdown function. the lna covers the 50mhz to 878mhz cable and terrestrial tv frequency range. in addition, the device includes a power detec- tor that can be used to control the agc function. the max3558 is available in a space-saving 28-pin qfn package. broadband lna the broadband lna input is differential and internally matched to 75 ? ? ? ? ?
max3558 quad-output lna with agc for cable tv applications 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. 8 _____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 ? 2003 maxim integrated products printed usa is a registered trademark of maxim integrated products. chip information transistor count: 4930 process: bipolar reference: 28-pin qfn 5mm 5mm package code: g2855-2 1 2 3 4 5 6 7 22 23 24 25 26 27 28 21 20 19 18 17 16 15 8910 11 12 13 14 power detector rfin r bias 1.1k ? ?
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