a udio max lxe1 701 u se r ? s g uide lxe1701 audiomax evaluation kit user?s guide l in fi nit y d iv is io n m i cro semi linfinity microele c tronics division 11861 western avenue, ga rden grove, ca. 9284 1, 714-89 8-812 1, fax: 714-8 93-25 70 page 1 cop y right ? 200 0 rev. 1.0, 2003 -0 5-28
a udio max lxe1 701 u se r ? s g uide lxe1701 evaluation boar d quick start guide the l x e 1 701 evaluation b o ard is a fully functional filterless m ono class - d am plifier. c o nnection t o a single powe r s u pply, even two aa batteries, one s p eaker, a n d an a u d i o sou r ce like po rtab le p l ay er o r co m p u t er is all th at is requ ired to b e g i n ev alu ating th e am p lifier. th e am p lifier will sup p o r t con tin uou s ou tput p o wer lev e ls u p to 2 w in t o 4 ? l o ad (< 10% th d+ n). boar d se ttin g 1. po wer a nd gr ou n d c o nnect i ons: t h e t e rm inal j3 i s f o r t h e po wer su pply co n n ection . vbat is connected to the p o s itiv e po larit y o f th e power su pp ly o r b a ttery (+1 . 8 v ~ +5v); t h e gnd is conn ected to th e n e g a tiv e polarity o f t h e p o w e r su pp ly o r b a tter y . pl ease m a k e su re yo ur p o w e r su pp ly po lar i t y co nn ection an d supp ly vo ltag e is co rr ect before you start to eval uate the board. 2. spea kers c o n n ect i on: j 4 i s t h e spea ker ou t put . c o n n ect spea ker ?+? a nd ? - ? to ?out+/out+? . t h is evaluation boa r d i s desi g n e d fo r > 4 ? s p eaker loa d s. 3 . aud i o inpu t co nn ection : j1 i s th e aud i o inpu t con n ection . th e po sitiv e au d i o inp u t s are co nn ected t o in+ p i n , wh ile th e n e g a tiv e inp u t s ar e conn ected to in - p i n. for sing le- e nd ed aud i o input, th e aud i o si gn al is con n ected to i n + and gr o u n d c o nnec t ed t o i n -. 4. ?ena bl e/ di sabl e? jum p er set t i ng: jp 2 is t h e jum p er for ?e nable/disable?. ena b l e j u m p er m u st be cl ose d f o r no rm al sy st em operat i on . 5. ?b w _ sel? ( b and w i d t h sel ect i on) j u m p er set t i ng: jp 3 i s for low fre quency cut off co r n er f r e que n c y sel ect i on. th ere are two ch o i ces: on e is 2 0 hz i f ?2 0hz? po sitio n is cl o s ed ; ano t h e r on e is 30 0hz if ?3 00hz? p o sitio n is clo s ed . 6. ?gain? jum p er setting: j p 1 is the jum p er for syste m ga in se lection. t h e r e are also two cho i ces: 14d b if ?1 4d b? p o s ition is cl o s ed ; 8d b if ?8db? po sitio n is clo s ed. 7 . ou t p u t selectio n ju m p er settin g : jp4 & jp5 is th e ju m p ers for lc filter o r filterless ou t p u t selectio n. defau lt setting is filterless out put, which ?filterless+? a n d ?filterless-? po sitions are cl ose d . l 1 /l2, c6/c7 are optional c o m pone nts for lc filter o u tp u t wh en ?lc+? and ?lc - ? p o s ition s are cl o s ed . l1 /l2 cou l d b e i n du ct o r s, or ferrite bead s for l o ng spea ker wi res out put t o s p ea k e r. 8. test set u p : r 1 / r 2/ r 3 / r 4/ r 5 & c 2 / c 3/ c 4 / c 5 are com p o n e nt s f o r t e st p u r p o se (re fer t o next pa ge sc he m a t i c ), t h ey are n o t n ecessary fo r th e real ap p lication circu it. th ey m a k e a seco nd o r der rc filter cu t tin g o f f th e h i gh switch i ng fre que ncy , t o m easure t h e a u di o si g n al m o re p r eci sel y . r 1 i s an o n - b oar d l o ad , ca n be 4 ~ 16 ? , 2w r e si sto r , you also can c o n n ect a r e si st or l o ad o f f t h e boa r d t h ro ug h t h e out put t e rm i n al wi t h o u t o n - b o ar d l o a d . the p r o b es j u st t o uc h ?test out+? and ?te s t o ut-? test point s , you ca n m easure au di o pe rf orm a nce o f t h e b o ar d act u al l y t h i s e v al uat i o n b o ar d i s a d ded a l o t o f opt i o nal c o m ponent s, o r f o r t e st p u r p ose, al so s o m e headers , t e rm i n al s fo r i n p u t an d o u t p ut , t h ey a r e n o t necessa ry f o r t h e real ap pl i cat i on. t h e real c o m pone nt f o r t h i s sy st em i s onl y o n e: c 1 , f o r th e pow er supply r i p p l e. ano t h e r app licatio n bo ard w e m a d e on ly h a s th is o n e co m p on en t on th e bo ar d ex cep t fo r t h e ic, y ou ca n fi n d t h e schem a t i c and pi ct ure i n t h e pa ge ? it i s s o l d se parat e l y . m i cro semi linfinity microele c tronics division 11861 western avenue, ga rden grove, ca. 9284 1, 714-89 8-812 1, fax: 714-8 93-25 70 page 2 cop y right ?
a udio max lxe1 701 u se r ? s g uide application schematic j3 1 2 vbat j1 1 2 au dio_in * fo r test p urpose l2 22uh c3 2200p f * f or test p urpose vbat l1 22uh r1 4/ 2w lxe1701 2w class-d a u dio a m plif ier evaluat i on m o dule j2 1 2 jp1 u1 lx 1701 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 ou t n pv d d pv d d ou tp pvss vss en bw_ sel ga i n vin n vin p to v l vdd 3le l vss pvss jp4 j4 1 2 th ermal indi cator r2 470 c7 4 70nf jp5 vbat + c1 47u f r3 47 0 vbat jp2 r4 470 gnd jp3 tp1 v bat c5 2200p f c4 470 0p f tp2 r5 47 0 c2 4700 p f vbat c6 4 70nf f i g ure 1 - lxe170 1 s chemati c * opera tion m i cro semi linfinity microele c tronics division 11861 western avenue, ga rden grove, ca. 9284 1, 714-89 8-812 1, fax: 714-8 93-25 70 page 3 cop y right ? 200 0 rev. 1.0, 2003 -0 5-28
a udio max lxe1 701 u se r ? s g uide board l ayout compone nt laye r solder laye r c o mponents placement f i g ure 2 - lxe170 1 pcb l ayout m i cro semi linfinity microele c tronics division 11861 western avenue, ga rden grove, ca. 9284 1, 714-89 8-812 1, fax: 714-8 93-25 70 page 4 cop y right ? 200 0 rev. 1.0, 2003 -0 5-28
a udio max lxe1 701 u se r ? s g uide t e s t procedures a udi o p r eci si o n sy s t e m o n e a udi o p r eci si o n sy s t e m o n e powe r su ppl y o u t put - ou t p u t + i npu t + i nput - in - in + ou t + out - vba t gn d + - l x 1701 c1 2 nd o r de r rc l p f 2 nd o r de r rc l p f o n -b o a rd r e s i s t or l oad tp + tp - gn d l x 1701 e v a l u a t i o n k i t f i g ure 3 - lxe170 1 t est s ys te m s etup equipm ents: audio precision system 1, oscillos c op e, power supply ~+5v; supply voltage: 1.8v/3.3v/5.0v 3 corner voltages on-board passive lpf: 40khz cut off frequency (-3db) on-board resistor load: 4/8 ? , 2w ap settings: 10hz ~ 22khz bpf m i cro semi linfinity microele c tronics division 11861 western avenue, ga rden grove, ca. 9284 1, 714-89 8-812 1, fax: 714-8 93-25 70 page 5 cop y right 200 0 rev. 1.0, 2003 -0 5-28
a udio max lxe1 701 u se r ? s g uide test procedures(cont.) thd+n vs. output pow er tested signal frequency f=1khz, through on-b oard pc lpf to m i ni m i ze the switching noise, keep m easuring accu racy thd+n vs. frequency tested signal level po=100mw , swe e p input sign al frequency from 20hz to 20khz, through on- board pc lpf to m i nimize th e switc hing noise, keep m easuring accu racy frequency response tested signal level po=100mw , swe e p input signal frequency from 20hz to 20khz, not throug h on-board pc lpf, directly test it f r o m out+ and out- change jp3, the bandwidth selection jum p er to change the hpf cutoff frequency, then m easur e it signal-to-noise ratio (snr) input short, output through tp1 and tp2 into ap input, ap is set up w ith fft digital analyze r function, a-weighted filter, 0db as maxim u m out put power with 1%thd+n efficiency output power vs. power supply power, since resistor is acting as a load even at high switchin g frequency, the on-board load resistor is rem o ved and the output through out+/out- i nto a speaker load becaus e th e speaker can act as an in ductor to cu t off the h i g h er switchin g frequenc y to keep m easuring accuracy. test ed signal is f=1khz sine wave. gain sa m e procedure with frequency respons e, set 0db as input signal level change jp1, the gain selection jum p er to change its gain, and m easure it m i cro semi linfinity microele c tronics division 11861 western avenue, ga rden grove, ca. 9284 1, 714-89 8-812 1, fax: 714-8 93-25 70 page 6 cop y right 200 0 rev. 1.0, 2003 -0 5-28
a udio max lxe1 701 u se r ? s g uide applications lxe1701spk* is evalu a tion / applica tion module; it has v e r y compac t size (22mm x 13mm). on the boa rd, ther e are only two componen ts, one is lx1701, and ano t her is a surface mount c a p 4.7uf. it is eas y for users to dire ctly embed this module in to speaker, conn e c t to the audio source and 2 or 3 ?aa? si ze batter i es, and then plug-p l ay ! * - it is sold se par a te ly. vbat ou t- ou t+ s1 spk+ s2 spk- in - vbat in + vbat u1 l x 1701 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 ou tn pvd d pvd d ou tp pvss vss en b w _ sel ga i n vin n vin p tovl vd d 3le l vss pvss vbat + c1 47u f a udi o i n - a udi o i n + f i g ure 4 - lx e1701spk e valuation /a ppl ic a t ion module m i cro semi linfinity microele c tronics division 11861 western avenue, ga rden grove, ca. 9284 1, 714-89 8-812 1, fax: 714-8 93-25 70 page 7 cop y right ? 200 0 rev. 1.0, 2003 -0 5-28
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