TS3410

TS3410 1 A / 1 .5 M H z S y n c h ro n o u s B u c k C o n v e rte r S O T -2 5 P in D e fin itio n : 1. EN 2 . G ro u n d 3 . S w itc h in g O u tp u t 4 . In p u t 5. Feedback General Description T S 3 4 1 0 is a h ig h e ffic ie n c y m o n o lith ic s y n c h r o n o u s b u c k r e g u la to r u s in g a c o n s ta n t fr e q u e n c y , c u r r e n t m o d e a r c h it e c t u r e . T h e d e v ic e is a v a ila b le in a n a d ju s t a b le v e r s io n . S u p p ly c u r r e n t w it h n o lo a d is 3 5 0 u A a n d d r o p s t o < 1 u A in s h u td o w n . T h e 2 .5 V to 6 .5 V in p u t v o lta g e r a n g e m a k e s T S 3 4 1 0 id e a lly s u ite d fo r s in g le L i- Io n , tw o to fo u r A A b a tte r y - p o w e r e d a p p lic a tio n s . 1 0 0 % d u ty c y c le p r o v id e s lo w d r o p o u t o p e r a tio n , e x te n d in g b a tte r y life in p o r ta b le s y s te m s . P W M p u ls e s k ip p in g m o d e o p e r a tio n p r o v id e s v e r y lo w o u tp u t r ip p le v o lta g e fo r n o is e s e n s itiv e a p p lic a tio n s . S w itc h in g fr e q u e n c y is in te r n a lly s e t a t 1 .5 M H z , a llo w in g th e u s e o f s m a ll s u r fa c e m o u n t in d u c to r s a n d c a p a c ito r s . T h e in te r n a l s y n c h r o n o u s s w itc h in c r e a s e s e ffic ie n c y a n d d e c r e a s e s n e e d o f a n e x te r n a l S c h o ttk y d io d e . L o w o u tp u t v o lta g e s a r e e a s ily s u p p o r te d w ith th e 0 .6 V fe e d b a c k r e fe r e n c e v o lta g e . Features ● ● ● ● ● ● ● ● ● ● ● H ig h E ffic ie n c y : U p to 9 6 % 2 .5 V to 6 .5 V In p u t V o lta g e R a n g e S h o r t C ir c u it P r o te c tio n ( S C P ) 1 .5 M H z C o n s ta n t F r e q u e n c y O p e r a tio n L o w D r o p o u t O p e r a tio n : 1 0 0 % D u ty C y c le 0 .6 V R e fe r e n c e A llo w s L o w O u tp u t V o lta g e s 1 A O u t p u t C u r r e n t a t V IN = 3 V & V O U T = 1 . 8 V L o w Q u ie s c e n t C u r r e n t: 3 5 0 u A N o S c h o ttk y D io d e R e q u ir e d in A p p lic a tio n ≤ 1 u A S h u td o w n C u rre n t C u r r e n t M o d e O p e r a tio n fo r E x c e lle n t L in e a n d L o a d T r a n s ie n t R e s p o n s e Application ● ● ● ● C e llu la r P h o n e s D ig ita l S till C a m e r a s P o r ta b le E le c tr o n ic s U S B D e v ic e s Pin Description Nam e EN GND SW D e s c r ip tio n P o w e r - o ff p in H ： n o r m a l o p e r a tio n L ： S te p - d o w n o p e r a tio n s to p p e d ( A ll c ir c u its d e a c tiv a te d ) G r o u n d p in S w itc h o u tp u t p in . C o n n e c t e x te r n a l in d u c to r h e r e . M in im iz e tr a c e a r e a a t th is p in to re d u c e E M I. IC p o w e r s u p p ly p in O u tp u t F e e d b a c k p in Ordering Information P a rt N o . TS3410CX5 RF Package S O T -2 5 P a c k in g 3K pcs/ 7” R eel VCC FB Application Circuit 1 /7 V e r s io n : A 0 8 TS3410 1 A / 1 .5 M H z S y n c h ro n o u s B u c k C o n v e rte r Absolute Maximum Rating C h a r a c te r is tic s V IN P i n V o l t a g e F e e d b a c k P in V o lta g e R U N P in V o lta g e S w itc h P in V o lta g e P e a k S W S in k & S o u r c e C u r r e n t O p e r a tin g S u p p ly V o lta g e P o w e r D is s ip a tio n S to ra g e T e m p e ra tu re R a n g e O p e r a tin g T e m p e r a tu r e R a n g e J u n c tio n T e m p e r a tu r e T h e r m a l R e s is ta n c e fr o m J u n c tio n to c a s e T h e r m a l R e s is ta n c e fr o m J u n c tio n to a m b ie n t Sym bol V IN V FB V RUN V SW I PSW V OP PD T ST T OP TJ θ JC θ JA 2 R a tin g G n d - 0 .3 to G n d + 7 G n d - 0 . 3 t o V IN + 0 . 3 G n d - 0 . 3 t o V IN + 0 . 3 G n d - 0 . 3 t o V IN + 0 . 3 1 .4 + 2 .5 to + 6 ( T J- T A ) / θ JA -4 0 to + 1 5 0 -4 0 to + 8 5 +125 110 250 U n it V V V V A V mW o o o o o C C C C /W C /W N o t e 1 : θ JA i s m e a s u r e d w i t h t h e P C B c o p p e r a r e a o f a p p r o x i m a t e l y 1 i n ( M u l t i - l a y e r ) . t h a t n e e d c o n n e c t t o G n d p i n o f th e T S 3 4 1 0 . Electrical Specifications (Ta = 25oC, VIN=VRUN=3.6V unless otherwise noted) C h a r a c te r is tic s F e e d b a c k V o lta g e Q u ie s c e n t C u r r e n t F e e d b a c k B ia s C u r r e n t S h u td o w n S u p p ly C u r r e n t M a x im u m O u tp u t C u r r e n t C u r r e n t L im it L in e R e g u la tio n L o a d R e g u la tio n O s c illa tio n F r e q u e n c y F re q u e n c y o f S C P R D S (O N ) o f P - C H M O S F E T R D S (O N ) o f N - C H M O S F E T E ffic ie n c y E N p in lo g ic In p u t T h r e s h o ld V o lta g e E N P in In p u t C u r r e n t Sym bol V FB I CCQ I FB I SD I O U T (M A X ) I L IM IT △ V O U T/ V O U T △ V O U T/ V O U T F OSC F OSC1 R DSON R DSON E FFI V ENL V ENH I EN C o n d itio n s T A = 2 5 ℃ , I OU T= 5 0 m A V FB= 0 . 5 V V FB = 0 . 6 5 V V RUN = 0 V V C C = 3 V , V OU T= 1 . 8 V V CC = 3 V V CC = 2 . 5 V ~ 5 . 5 V I OUT = 0 . 0 1 t o 0 . 6 A S W p in S W p in I SW = 3 0 0 m A I SW = - 3 0 0 m A V O U T= 3 . 3 V , I O U T= 0 . 5 A M in 0 .5 8 8 ---1 1 .2 --1 .2 ----0 .6 --- Typ 0 .6 350 -0 .1 -1 .4 0 .0 4 0 .5 1 .5 300 0 .4 0 0 .3 5 92 --± 0 .1 M ax 0 .6 1 2 450 ±30 1 --0 .4 -1 .8 -0 .4 5 0 .4 0 --1 .2 ±1 U n its V uA nA uA A A % % MHz KHz Ω Ω % V uA N o te 2 : 1 0 0 % p r o d u c tio n te s t a t + 2 5 ° C . S p e c ific a tio n s o v e r th e te m p e r a tu r e r a n g e a r e g u a r a n te e d b y d e s ig n a n d c h a r a c te r iz a tio n . 2 /7 V e r s io n : A 0 8 TS3410 1 A / 1 .5 M H z S y n c h ro n o u s B u c k C o n v e rte r Block Diagram Function Description O p e r a tio n T S 3 4 1 0 is a m o n o lith ic s w itc h in g m o d e S te p - D o w n D C - D C c o n v e r te r . It u tiliz e s in te r n a l M O S F E T s to a c h ie v e h ig h e ffic ie n c y a n d c a n g e n e r a te v e r y lo w o u tp u t v o lta g e b y u s in g in te r n a l r e fe r e n c e a t 0 .6 V . It o p e r a te s a t a fix e d s w itc h in g fr e q u e n c y , a n d u s e s th e s lo p e c o m p e n s a te d c u r r e n t m o d e a r c h ite c tu r e . T h is S te p - D o w n D C - D C C o n v e r te r s u p p lie s 1 A o u t p u t c u r r e n t a t V OUT = 1 . 8 V w i t h i n p u t v o l t a g e r a n g e f r o m 2 . 5 V t o 6 V . C u rre n t M o d e P W M C o n tro l S lo p e c o m p e n s a te d c u r r e n t m o d e P W M c o n tr o l p r o v id e s s ta b le s w itc h in g a n d c y c le - b y - c y c le c u r r e n t lim it fo r e x c e lle n t lo a d a n d lin e r e s p o n s e s a n d p r o te c tio n o f th e in te r n a l m a in s w itc h ( P - C H M O S F E T ) a n d s y n c h r o n o u s r e c tifie r ( N - C H M O S F E T ) . D u r in g n o r m a l o p e r a tio n , th e in te r n a l P - C H M O S F E T is tu r n e d o n fo r a c e r ta in tim e to r a m p th e in d u c to r c u r r e n t a t e a c h r is in g e d g e o f th e in te r n a l o s c illa to r , a n d s w itc h e d o ff w h e n th e p e a k in d u c to r c u r r e n t is a b o v e th e e r r o r v o lta g e . T h e c u r r e n t c o m p a r a to r , IC O M P , lim its th e p e a k in d u c to r c u r r e n t. W h e n th e m a in s w itc h is o ff, th e s y n c h r o n o u s r e c tifie r w ill b e tu r n e d o n im m e d ia te ly a n d s ta y o n u n til e ith e r th e in d u c to r c u r r e n t s ta r ts to r e v e r s e , a s in d ic a te d b y th e c u r r e n t r e v e r s a l c o m p a r a to r , IZ E R O , o r th e b e g in n in g o f th e n e x t c lo c k c y c le . T h e O V D E T c o m p a r a to r c o n tr o ls o u tp u t tr a n s ie n t o v e r s h o o ts b y tu r n in g th e m a in s w itc h o ff a n d k e e p in g it o ff u n til th e fa u lt is n o lo n g e r p r e s e n t. Id le M o d e O p e r a tio n A t v e r y lig h t lo a d s , T S 3 4 1 0 a u to m a tic a lly e n te r s p u ls e s k ip p in g M o d e . In th e p u ls e s k ip p in g M o d e , th e in d u c to r c u r r e n t m a y r e a c h z e r o o r r e v e r s e o n e a c h p u ls e . T h e P W M c o n tr o l lo o p w ill a u to m a tic a lly s k ip p u ls e s to m a in ta in o u tp u t r e g u la tio n . T h e b o tto m M O S F E T is tu r n e d o ff b y th e c u r r e n t r e v e r s a l c o m p a r a to r , IZ E R O , a n d th e s w itc h v o lta g e w ill r in g . T h is is d is c o n tin u o u s m o d e o p e r a tio n , a n d is n o r m a l b e h a v io r fo r th e s w itc h in g r e g u la to r . 3 /7 V e r s io n : A 0 8 TS3410 1 A / 1 .5 M H z S y n c h ro n o u s B u c k C o n v e rte r Function Description (Continue) M a x im u m L o a d C u r r e n t T h e T S 3 4 1 0 w ill o p e r a te w ith in p u t s u p p ly v o lta g e a s lo w a s 2 .5 V , h o w e v e r , th e m a x im u m lo a d c u r r e n t d e c r e a s e s a t lo w e r in p u t d u e to la r g e IR d r o p o n th e m a in s w itc h a n d s y n c h r o n o u s r e c tifie r . T h e s lo p e c o m p e n s a tio n s ig n a l r e d u c e s th e p e a k in d u c to r c u r r e n t a s a fu n c tio n o f th e d u ty c y c le to p r e v e n t s u b - h a r m o n ic o s c illa tio n s a t d u ty c y c le s g r e a te r th a n 5 0 % . C o n v e r s e ly th e c u r r e n t lim it in c r e a s e s a s th e d u ty c y c le d e c r e a s e s . Application Information S e ttin g th e O u tp u t V o lta g e A p p lic a t io n c ir c u it it e m s h o w s t h e b a s ic a p p lic a t io n c ir c u it w it h T S 3 4 1 0 a d ju s t a b le o u t p u t v e r s io n . T h e e x t e r n a l r e s is t o r s e ts th e o u tp u t v o lta g e a c c o r d in g to th e fo llo w in g e q u a tio n : T a b le 1 : R e s is to r S e le c t fo r O u tp u t V o lta g e S e ttin g VOUT R2 R1 1 .2 V 300K 300K 1 .5 V 300K 450K 1 .8 V 300K 600K 2 .5 V 300K 950K In d u c to r S e le c tio n F o r m o s t d e s ig n s , th e T S 3 4 1 0 o p e r a te s w ith in d u c to r s o f 1 µ H to 4 .7 µ H . L o w in d u c ta n c e v a lu e s a r e p h y s ic a lly s m a lle r b u t r e q u ir e fa s te r s w itc h in g , w h ic h r e s u lts in s o m e e ffic ie n c y lo s s . T h e in d u c to r v a lu e c a n b e d e r iv e d fr o m th e fo llo w in g e q u a tio n : T a b le 2 : In d u c to r S e le c t fo r O u tp u t V o lta g e S e ttin g ( V c c - 3 .6 V ) VOUT 1 .2 V 1 .5 V 1 .8 V 2 .5 V In d u c to r 2 .2 u H 2 .2 u H 2 .2 u H 2 .2 u H P a rt N u m b e r 7440430027 7440430027 W E -T P C N o te : P a r t T y p e M H o r M ( w w w .w e - o n lin e .c o m ) 7440430027 7440430022 W h e r e is in d u c to r R ip p le C u r r e n t. L a r g e v a lu e in d u c to r s lo w e r r ip p le c u r r e n t a n d s m a ll v a lu e in d u c to r s r e s u lt in h ig h r ip p le c u r r e n ts . C h o o s e in d u c to r r ip p le c u r r e n t a p p r o x im a te ly 3 5 % o f th e m a x im u m lo a d c u r r e n t 1 A , ∆ IL = 3 5 0 m A . F o r o u tp u t v o lta g e s a b o v e 2 .0 V , w h e n lig h t- lo a d e ffic ie n c y is im p o r ta n t, th e m in im u m r e c o m m e n d e d in d u c to r is 2 .2 µ H . F o r o p tim u m v o lta g e - p o s itio n in g lo a d tr a n s ie n ts , c h o o s e a n in d u c to r w ith D C s e r ie s r e s is ta n c e in th e 5 0 m Ω to 1 5 0 m Ω r a n g e . F o r h ig h e r e ffic ie n c y a t h e a v y lo a d s ( a b o v e 2 0 0 m A ) , o r m in im a l lo a d r e g u la tio n ( b u t s o m e tr a n s ie n t o v e r s h o o t) , th e r e s is ta n c e s h o u ld b e k e p t b e lo w 1 0 0 m Ω . T h e D C c u r r e n t r a tin g o f th e in d u c to r s h o u ld b e a t le a s t e q u a l to th e m a x im u m lo a d c u r r e n t p lu s h a lf th e r ip p le c u r r e n t to p r e v e n t c o r e s a tu r a tio n ( 1 A + 1 7 0 m A ) . In p u t C a p a c ito r S e le c tio n T h e in p u t c a p a c ito r r e d u c e s th e s u r g e c u r r e n t d r a w n fr o m th e in p u t a n d s w itc h in g n o is e fr o m th e d e v ic e . T h e in p u t c a p a c ito r im p e d a n c e a t th e s w itc h in g fr e q u e n c y s h a ll b e le s s th a n in p u t s o u r c e im p e d a n c e to p r e v e n t h ig h fr e q u e n c y s w itc h in g c u r r e n t p a s s in g to th e in p u t. A lo w E S R in p u t c a p a c ito r s iz e d fo r m a x im u m R M S c u r r e n t m u s t b e u s e d . C e r a m ic c a p a c ito r s w ith X 5 R o r X 7 R d ie le c tr ic s a r e h ig h ly r e c o m m e n d e d b e c a u s e o f th e ir lo w E S R a n d s m a ll te m p e r a tu r e c o e ffic ie n ts . A 4 .7 µ F c e r a m ic c a p a c ito r fo r m o s t a p p lic a tio n s is s u ffic ie n t. 4 /7 V e r s io n : A 0 8 TS3410 1 A / 1 .5 M H z S y n c h ro n o u s B u c k C o n v e rte r Application Information (Continue) O u tp u t C a p a c ito r S e le c tio n T h e o u tp u t c a p a c ito r is r e q u ir e d to k e e p th e o u tp u t v o lta g e r ip p le s m a ll a n d to e n s u r e r e g u la tio n lo o p s ta b ility . T h e o u tp u t c a p a c ito r m u s t h a v e lo w im p e d a n c e a t th e s w itc h in g fr e q u e n c y . C e r a m ic c a p a c ito r s w ith X 5 R o r X 7 R d ie le c tr ic s a r e r e c o m m e n d e d d u e to th e ir lo w E S R a n d h ig h r ip p le c u r r e n t. C o m p e n s a tio n C a p a c ito r S e le c tio n T h e c o m p e n s a tio n c a p a c ito r s fo r in c r e a s in g p h a s e m a r g in p r o v id e a d d itio n a l s ta b ility . It is r e q u ir e d a n d m o r e th a n 2 2 p , R e fe r to D e m o B o a r d S c h e m a tic , T h e o p tim u m v a lu e s fo r C 3 is 4 7 p F . 5 /7 V e r s io n : A 0 8 TS3410 1 A / 1 .5 M H z S y n c h ro n o u s B u c k C o n v e rte r S O T -2 5 M e c h a n ic a l D r a w in g D IM A+A1 B C D E E H L Ө1 S1 S O T -2 5 D IM E N S IO N M IL L IM E T E R S IN C H E S M IN MAX M IN MAX. 0 .0 9 1 .2 5 0 .0 3 5 4 0 .0 4 9 2 0 .3 0 0 .5 0 0 .0 1 1 8 0 .0 1 9 7 0 .0 9 0 .2 5 0 .0 0 3 5 0 .0 0 9 8 2 .7 0 3 .1 0 0 .1 0 6 3 0 .1 2 2 0 1 .4 0 1 .8 0 0 .0 5 5 1 0 .0 7 0 9 1 .9 0 B S C 0 .0 7 4 8 B S C 2 .4 0 3 .0 0 0 .0 9 4 4 9 0 .1 1 8 1 0 .3 5 B S C 0 .0 1 3 8 B S C 0º 10º 0º 10º 0 .9 5 B S C 0 .0 3 7 4 B S C 6 /7 V e r s io n : A 0 8 TS3410 1 A / 1 .5 M H z S y n c h ro n o u s B u c k C o n v e rte r N o t ic e S p e c if ic a t io n s o f t h e p r o d u c t s d is p la y e d h e r e in a r e s u b je c t t o c h a n g e w it h o u t n o t ic e . T S C o r a n y o n e o n it s b e h a lf , a s s u m e s n o r e s p o n s ib ility o r lia b ility fo r a n y e r r o r s o r in a c c u r a c ie s . In fo r m a tio n c o n ta in e d h e r e in is in te n d e d to p r o v id e a p r o d u c t d e s c r ip tio n o n ly . N o lic e n s e , e x p r e s s o r im p lie d , to a n y in te lle c tu a l p r o p e r ty r ig h ts is g r a n te d b y th is d o c u m e n t. E x c e p t a s p r o v id e d in T S C ’s te r m s a n d c o n d itio n s o f s a le fo r s u c h p r o d u c ts , T S C a s s u m e s n o lia b ility w h a ts o e v e r , a n d d is c la im s a n y e x p r e s s o r im p lie d w a r r a n ty , r e la tin g to s a le a n d /o r u s e o f T S C p r o d u c ts in c lu d in g lia b ility o r w a r r a n tie s r e la tin g to fitn e s s fo r a p a r tic u la r p u r p o s e , m e r c h a n ta b ility , o r in fr in g e m e n t o f a n y p a te n t, c o p y r ig h t, o r o th e r in te lle c tu a l p r o p e r ty r ig h t. T h e p r o d u c ts s h o w n h e r e in a r e n o t d e s ig n e d fo r u s e in m e d ic a l, life - s a v in g , o r life - s u s ta in in g a p p lic a tio n s . C u s to m e r s u s in g o r s e llin g th e s e p r o d u c ts fo r u s e in s u c h a p p lic a tio n s d o s o a t th e ir o w n r is k a n d a g r e e to fu lly in d e m n ify T S C fo r a n y d a m a g e s r e s u ltin g fr o m s u c h im p r o p e r u s e o r s a le . 7 /7 V e r s io n : A 0 8