general description the max9892 is an audio click-and-pop eliminator forportable multimedia devices. operating from a 1.7v to 3.6v supply, the max9892 connects to the output of the existing system amplifier and provides a low-imped- ance path to ground during startup and shutdown. the inputs inl and inr accept voltage swings from v dd to 5.5v below v dd . see the setting the supply voltage section for more information. the power-up and power-down transients are shunted to ground to prevent clicks and pops from becoming audible. the max9892 features two low-impedance analog switches controlled by mute that opens and closes the switches. the switches are open during normal opera-tion and have no impact on the output signal. during startup and shutdown of the amplifier, the max9892 can be activated to short the outputs to ground and prevent clicks and pops from pulling current through the headphones. the max9892 is available in 6-bump ucsp (1mm x 1.52mm x 0.6mm) and 6-pin ?fn (2mm x 2mm x 0.75mm) packages. the max9892 is specified over the -40? to +85? temperature range. applications mobile phonessmart phones mobile internet devices portable gaming consoles portable media players notebook computers features ? distortion-free, click-and-pop elimination ? less than 1? supply current ? 1.7v to 3.6v single-supply operation ? tiny packages 6-bump ucsp (1mm x 1.52mm x 0.6mm)6-pin ?fn (2mm x 2mm x 0.75mm) max9892 shunt mode audio click-and-pop eliminator ________________________________________________________________ maxim integrated products 1 19-4295; rev 0; 10/08 for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. + denotes a lead-free/rohs-compliant package. 123 a b ucsp top view (bumps on bottom) inl gnd inr v dd set mute 43 inl mute 52 gnd v dd 61 inr set dfn top view max9892 max9892 + pin configurations max9892 mute set c set v dd gnd 1.7v to 3.6v headphone amplifier inl inr r series r series 0.1 f typical operating circuit ordering information part temp range pin-package MAX9892ERT+ -40? to +85? 6 ucsp max9892elt+ -40? to +85? 6 ?fn downloaded from: http:///
max9892 shunt mode audio click-and-pop eliminator 2 _______________________________________________________________________________________ absolute maximum ratingselectrical characteristics (v dd = 3.0v, v gnd = 0, t a = t min to t max , unless otherwise noted. typical values are at t a = +25?.) (note 1) stresses beyond those listed under ?bsolute 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. v dd , mute , set to gnd..........................................-0.3v to +6v inl, inr to gnd .................................(v dd - 6v) to (v dd + 0.3v) continuous current in/out of v dd ......................................30ma continuous current in/out of mute ...................................30ma continuous current in/out of set.......................................30ma continuous current in/out of inl, inr and gnd .............390ma continuous power dissipation (t a = +70?) 6-bump ucsp (derate 3.9mw/? above +70?) .....308.3mw 6-pin ?fn (derate 4.5mw/? above +70?) ..........357.8mw operating temperature range ...........................-40? to +85? junction temperature ......................................................+150? storage temperature range .............................-65? to +150? lead temperature (soldering, 10s) .................................+300? bump temperature (soldering) reflow ..........................................................................+235? parameter symbol conditions min typ max units supply voltage range v dd guaranteed by r on test 1.7 5.5 v recommended supply voltagerange v dd (note 2) 1.7 3.6 v supply current i dd v dd = 5.5v, t a = +25? (note 3) 0.6 1 a input voltage range v in guaranteed by input leakage current test v dd - 5.5v v dd v turn-on time (figure 1) t on measured from mute = gnd and input voltage settled to 90% of its final value 130 ns c set = 500pf 4 10 17 c set = 50pf 1 turn-off time (figure 1) t off c set = 50nf 1000 ms turn-on time resistor r set c set = 500pf 350 800 1300 k v dd = 3.0v 0.3 v dd = 1.7v 2 switch on-resistance r on v dd = 5.5v 1 click-and-pop reduction r series = 30 , r load = 16 35 db v in = v dd - 5.5v, v dd = 1.7v ? input leakage current i in t a = +25? v in = v dd , v dd = 5.5v ? ? mute leakage current i mute v dd = 5.5v, v mute = 0 or 5.5v, t a = +25? ? ? mute input-voltage high v ih 1.5 v mute input-voltage low v il 0.4 v note 1: all devices are 100% production tested at t a = +25?. all temperature limits are guaranteed by design. note 2: operating within the recommended supply voltage range ensures that negative audio signals are not limited by the device.supply voltages above the recommended supply voltage range may limit the headphone amplifier? maximum output voltage. note 3: supply current is measured when switches are off. downloaded from: http:///
max9892 shunt mode audio click-and-pop eliminator _______________________________________________________________________________________ 3 -90 -70-80 -50-60 -40 -30 -10-20 0 02 0 10 40 30 60 50 80 70 100 90 click and pop vs. r series max9892 toc01 r series ( ) click and pop (dbv) tested with the max4338 out of shutdown into shutdown 0 600400 200 800 1000 1200 02 0 15 5 10 253035404550 t off vs. c set max9892 toc02 c set (nf) t off (ms) 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 1.5 2.5 3.5 4.5 5.5 r on vs. supply voltage max9892 toc03 v dd (v) r on ( ) 0 0.2 0.60.4 0.8 1.0 supply current vs. supply voltage max9892 toc04 v dd (v) i dd ( a) 1.5 3.5 2.5 4.5 5.5 -100 -80 -40-60 -20 0 click and pop vs. v dd max9892 toc05 v dd (v) click and pop (dbv) 1.5 3.5 2.5 4.5 5.5 tested with the max4338 out of shutdown into shutdown 2ms/div switch turn-off/on time mute2v/div max9892 toc06 in_2v/div c set = 500pf crosstalk vs. frequency max9892 toc07 frequency (khz) crosstalk (db) 10 1 0.1 -100 -80 -60 -40 -20 0 -120 0.01 100 typical operating characteristics (v dd = 3.0v, v gnd = 0, t a = +25?, unless otherwise noted.) downloaded from: http:///
max9892 shunt mode audio click-and-pop eliminator 4 _______________________________________________________________________________________ pin description ucsp ?fn bump pin name function a1 1 inl left-channel input. connect inl in between the output coupling capacitor and the headphonejack. a2 2 gnd ground a3 3 inr right-channel input. connect inr in between the output coupling capacitor and theheadphone jack. b1 6 mute active-low enable b2 5 v dd power supply b3 4 set turn-off time set. connect an external capacitor in between set and gnd to set the switchopen delay; see the setting the turn-off time section for more information. mute in_ r on 0.5 v dd v dd - 5.5v gnd gnd t off t on timing diagram figure 1. turn-on/off time downloaded from: http:///
detailed description the max9892 is the second-generation click-and-popeliminator designed to be used with conventional head- phone amplifiers. the max9892 works by adding a low- impedance current path from the headphone side of the dc-blocking capacitor to ground. drive mute low when turning off the amplifier, and high when enablingthe amplifier. a short turn-on time allows the switches in the max9892 to close before the dc-blocking capaci- tors have significantly discharged, eliminating clicks and pops at amplifier turn-off. an adjustable turn-off time allows the delay to be set to mask all clicks and pops during amplifier turn-on. setting the turn-off time the max9892 features a set input that allows the turn-off time to be adjusted from 1ms to 1000ms to match the click-and-pop profile of the amplifier startup. the value of an external capacitor sets the switch open delay, as shown in the following equation: t on (ms) = 0.02 x c set (pf) when the headphone amplifier is enabled, themax9892 automatically waits the set delay time before opening the analog switches. this allows amplifier turn- on click and pop to be eliminated. applications information setting the supply voltage the max9892 operates from 1.7v to 3.6v supply volt-age. the inputs, inl and inr, accept voltage swings from v dd to v dd - 5.5v. the audio signal applied to a headphone is ground biased, meaning that the signalswings just as much negative as positive. since the max9892 input voltage is limited to v dd - 5.5v on the negative side, the voltage on v dd must be set properly to pass the audio signal when the switch is open(figure 2). a voltage-divider can be used to scale down an avail- able supply voltage as shown in figure 3. the voltage- divider allows the creation of a supply voltage for the max9892 that is low enough to allow the negative por- tion of the audio signal to pass. when using large resis- tances for the voltage-divider, the supply current affects what resistors to use. select r 2 between 10k to 1m for a given supply voltage. use the following equation to calculate the r 1 : where v amp is the supply voltage of the amplifier, and i 2 is the current through r 2 . for a signal of ?v in refer- ence to gnd, the max9892 supply can be set from 2vto 3.5v. selecting series resistors a series resistor (r series ), as shown in the typical operating circuit , is necessary to achieve optimal click- and-pop reduction. see the click and pop vs. r series graph in the typical operating characteristics for details on how much click-and-pop reduction to expectfor a given series resistor. layout considerations bypass v dd to gnd with a 0.1? capacitor. the 0.1? bypass capacitor should be positioned as close aspossible to v dd . minimize trace length from gnd to solid system ground plane to ensure optimum perfor-mance. refer to the max9892 evaluation kit for a proven pcb layout. r vv ii amp dd dd 1 2 = + () max9892 shunt mode audio click-and-pop eliminator _______________________________________________________________________________________ 5 in_ v dd - 5.5v gnd v dd in_ gnd v dd a b v dd - 5.5v figure 2. proper supply selected for a given input signal. a: supply voltage with a large signal; b: supply voltage with a small signal downloaded from: http:///
max9892 ucsp applications information for the latest application details on ucsp construction,dimensions, tape-carrier information, printed circuit board techniques, bump-pad layout, and recommend- ed reflow temperature profile, as well as the latest infor- mation on reliability testing results, refer to application note 1891: understanding the basics of the wafer- level chip-scale package (wl-csp) at www.maxim- ic.com/ucsp . see figure 4 for the recommended max9892 pcb footprint. shunt mode audio click-and-pop eliminator 6 _______________________________________________________________________________________ v dd gnd headphone amp v dd 0.1 f r 1 r 2 max9892 figure 3. scaling down the supply voltage with a voltage divider 250 m 45 5 m figure 4. pcb footprint recommendation diagram chip information process: bicmos downloaded from: http:///
max9892 shunt mode audio click-and-pop eliminator _______________________________________________________________________________________ 7 package information for the latest package outline information and land patterns, go to www.maxim-ic.com/packages . ucsp.eps package type package code document no. 6 ucsp r6-1a1+1 21-0228 6 ?fn l622-1 21-0164 downloaded from: http:///
max9892 shunt mode audio click-and-pop eliminator 8 _______________________________________________________________________________________ package information (continued) for the latest package outline information and land patterns, go to www.maxim-ic.com/packages . 6, 8, 10l udfn.eps even terminal l c odd terminal l c l e l a e e d pin 1 index area b e a b n solder mask coverage a a 1 pin 1 0.10x45 l l1 (n/2 -1) x e) sample marking a1 a2 7 package outline,6, 8, 10l udfn, 2x2x0.80 mm 21-0164 b 1 2 aaaaaa downloaded from: http:///
max9892 shunt mode audio click-and-pop eliminator 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. maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 _____________________ 9 2008 maxim integrated products is a registered trademark of maxim integrated products, inc. package information (continued) for the latest package outline information and land patterns, go to www.maxim-ic.com/packages . common dimensions symbol min. nom. a 0.70 0.75 a1 d 1.95 2.00 e 1.95 2.00 l 0.30 0.40 pkg. code n e b package variations l1 6 l622-1 0.65 bsc 0.300.05 0.250.05 0.50 bsc 8 l822-1 0.200.03 0.40 bsc 10 l1022-1 2.05 0.80 max. 0.50 2.05 0.10 ref. (n/2 -1) x e 1.60 ref. 1.50 ref. 1.30 ref. a2 - 0.15 0.20 0.25 0.020 0.025 0.035 package outline,6, 8, 10l udfn, 2x2x0.80 mm 21-0164 b 2 2 downloaded from: http:///
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