Ptn78000w 1.5-A, Wide-Input Adjustable Switching Regulator

8/4/2019 Ptn78000w 1.5-A, Wide-Input Adjustable Switching Regulator

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1 F E A T U R E S D E S C R I P T I O N

A P P L I C A T I O N S

S T A N D A R D A P P L I C A T I O N

PTN78000

(Top View)

1

1

2

3

5

4

+

RSET

(B)

0.05 W, 1 %

(Required)

CI(A)

Ceramic

(Required)

CO

(A)

100 mF

Electrolytic

(Required)

VO

GND

VI

Inhibit

GND

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H

w w w . t i . c o m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S L T S 2 3 0 C N O V E M B E R 2 0 0 4 R E V I S E D S E P T E M B E R 2 0 0 8

1 . 5 - A , W I D E - I N P U T A D J U S T A B L E S W I T C H I N G R E G U L A T O R

1 . 5 - A O u t p u t C u r r e n t

W i d e - I n p u t V o l t a g e T h e P T N 7 8 0 0 0 i s a s e r i e s o f h i g h - e f f i c i e n c y , s t e p - d o w n I n t e g r a t e d S w i t c h i n g R e g u l a t o r s ( I S R ) , ( 7 V t o 3 6 V ) / ( 1 5 V t o 3 6 V ) t h a t r e p r e s e n t t h e t h i r d g e n e r a t i o n i n t h e e v o l u t i o n o f

W i d e - O u t p u t V o l t a g e A d j u s t t h e p o p u l a r 7 8 S T 1 0 0 s e r i e s o f p r o d u c t s . I n n e w

( 2 . 5 V t o 1 2 . 6 V ) / ( 1 1 . 8 5 V t o 2 2 V ) d e s i g n s i t s h o u l d b e c o n s i d e r e d i n p l a c e o f t h e H i g h E f f i c i e n c y ( U p t o 9 5 % ) 7 8 S T 1 0 0 , P T 7 8 S T 1 0 0 , P T 5 1 0 0 , a n d P T 6 1 0 0 s e r i e s

o f s i n g l e i n - l i n e p i n ( S I P ) p r o d u c t s . T h e P T N 7 8 0 0 0 i s O n / O f f I n h i b i t s m a l l e r a n d l i g h t e r t h a n i t s p r e d e c e s s o r s , a n d h a s

U n d e r v o l t a g e L o c k o u t e i t h e r s i m i l a r o r i m p r o v e d e l e c t r i c a l p e r f o r m a n c e

O u t p u t C u r r e n t L i m i t c h a r a c t e r i s t i c s . T h e c a s e - l e s s , d o u b l e - s i d e d p a c k a g e , a l s o e x h i b i t s i m p r o v e d t h e r m a l c h a r a c t e r i s t i c s , a n d i s O v e r t e m p e r a t u r e S h u t d o w n c o m p a t i b l e w i t h T I ' s r o a d m a p f o r R o H S a n d l e a d - f r e e

O p e r a t i n g T e m p e r a t u r e : 4 0 C t o 8 5 C c o m p l i a n c e .

S u r f a c e M o u n t P a c k a g e A v a i l a b l e O p e r a t i n g f r o m a w i d e - i n p u t v o l t a g e r a n g e , t h e P T N 7 8 0 0 0 p r o v i d e s h i g h - e f f i c i e n c y , s t e p - d o w n v o l t a g e c o n v e r s i o n f o r l o a d s o f u p t o 1 . 5 A . T h e

G e n e r a l - P u r p o s e , I n d u s t r i a l C o n t r o l s , o u t p u t v o l t a g e i s s e t u s i n g a s i n g l e e x t e r n a l r e s i s t o r . H V A C S y s t e m s , T e s t a n d M e a s u r e m e n t , T h e P T N 7 8 0 0 0 W m a y b e s e t t o a n y v a l u e w i t h i n t h e M e d i c a l I n s t r u m e n t a t i o n , A C / D C A d a p t o r s , r a n g e , 2 . 5 V t o 1 2 . 6 V , a n d t h e P T N 7 8 0 0 0 H f r o m V e h i c l e s , M a r i n e , a n d A v i o n i c s 1 1 . 8 5 V t o 2 2 V . T h e o u t p u t v o l t a g e o f t h e

P T N 7 8 0 0 0 W c a n b e a s l i t t l e a s 2 V l o w e r t h a n t h e i n p u t , a l l o w i n g o p e r a t i o n d o w n t o 7 V , w i t h a n o u t p u t v o l t a g e o f 5 V . T h e o u t p u t v o l t a g e o f t h e P T N 7 8 0 0 0 H c a n b e a s l i t t l e a s 3 V l o w e r t h a n t h e i n p u t , a l o w i n g o p e r a t i o n d o w n t o 1 5 V , w i t h a n o u t p u t v o l t a g e o f 1 2 V .

T h e P T N 7 8 0 0 0 h a s u n d e r v o l t a g e l o c k o u t a n d a n i n t e g r a l o n / o f f i n h i b i t . T h e m o d u l e s a r e s u i t e d t o a w i d e v a r i e t y o f g e n e r a l - p u r p o s e a p p l i c a t i o n s t h a t o p e r a t e o f f 1 2 - V , 2 4 - V , o r 2 8 - V D C p o w e r .

( A ) S e e t h e A p p l i c a t i o n I n f o r m a t i o n s e c t i o n f o r c a p a c i t o r r e c o m m e n d a t i o n s . T h e m i n i m u m i n p u t c a p a c i t a n c e i s 2 . 2 F f o r P T N 7 8 0 0 0 W , a n d 9 . 4 F ( 2

x 4 . 7 F ) f o r P T N 7 8 0 0 0 H .

( B ) R S E T i s r e q u i r e d t o a d j u s t t h e o u t p u t v o l t a g e h i g h e r t h a n 2 . 5 V f o r P T N 7 8 0 0 0 W , a n d h i g h t h a n 1 1 . 8 2 4 V f o r P T N 7 8 0 0 0 H . S e e t h e A p p l i c a t i o n I n f o r m a t i o n s e c t i o n f o r s p e c i f i c v a l u e s .

1

P l e a s e b e a w a r e t h a t a n i m p o r t a n t n o t i c e c o n c e r n i n g a v a i l a b i l i t y , s t a n d a r d w a r r a n t y , a n d u s e i n c r i t i c a l a p p l i c a t i o n s o f T e x a s I n s t r u m e n t s s e m i c o n d u c t o r p r o d u c t s a n d d i s c l a i m e r s t h e r e t o a p p e a r s a t t h e e n d o f t h i s d a t a s h e e t .

P R O D U C T I O N D A T A i n f o r m a t i o n i s c u r r e n t a s o f p u b l i c a t i o n d a t e . C o p y r i g h t 2 0 0 4 2 0 0 8 , T e x a s I n s t r u m e n t s I n c o r p o r a t e d P r o d u c t s c o n f o r m t o s p e c i f i c a t i o n s p e r t h e t e r m s o f t h e T e x a s I n s t r u m e n t s s t a n d a r d w a r r a n t y . P r o d u c t i o n p r o c e s s i n g d o e s n o t

n e c e s s a r i ly i n c l u d e t e s t i n g o f a l l p a r a m e t e r s .
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A B S O L U T E M A X I M U M R A T I N G S ( 1 )

R E C O M M E N D E D O P E R A T I N G C O N D I T I O N S

P A C K A G E S P E C I F I C A T I O N S

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H

S L T S 2 3 0 C N O V E M B E R 2 0 0 4 R E V I S E D S E P T E M B E R 2 0 0 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . w w w . t i . c o m

T h e s e d e v i c e s h a v e l i m i t e d b u i l t - i n E S D p r o t e c t i o n . T h e l e a d s s h o u l d b e s h o r t e d t o g e t h e r o r t h e d e v i c e p l a c e d i n c o n d u c t i v e f o a m d u r i n g s t o r a g e o r h a n d l i n g t o p r e v e n t e l e c t r o s t a t i c d a m a g e t o t h e M O S g a t e s .

O R D E R I N G I N F O R M A T I O N

F o r t h e m o s t c u r r e n t p a c k a g e a n d o r d e r i n g i n f o r m a t i o n , s e e t h e P a c k a g e O p t i o n A d d e n d u m a t t h e e n d o f t h i s d a t a s h e e t , o r s e e t h e T I w e b s i t e a t w w w . t i . c o m .

o v e r o p e r a t i n g f r e e - a i r t e m p e r a t u r e r a n g e u n l e s s o t h e r w i s e n o t e d , a l l v o l t a g e s w i t h r e s p e c t t o G N D ( p i n 1 ) ,

P T N 7 8 0 0 0 W U N I T

TA O p e r a t i n g f r e e - a i r t e m p e r a t u r e O v e r V I r a n g e 4 0 t o 8 5

S u r f a c e t e m p e r a t u r e o f m o d u l e b o d y H o r i z o n t a l T H ( s u f f i x A H ) 2 6 0 W a v e s o l d e r t e m p e r a t u r e

o r p i n s ( 5 s e c o n d s ) C

H o r i z o n t a l S M D ( s u f f i x A S ) 2 3 5 S u r f a c e t e m p e r a t u r e o f m o d u l e b o d y S o l d e r r e f l o w t e m p e r a t u r e

o r p i n s H o r i z o n t a l S M D ( s u f f i x A Z ) 2 6 0

Ts t g S t o r a g e t e m p e r a t u r e 5 5 t o 1 2 5

VI I n p u t s u r g e v o l t a g e , 1 0 m s m a x i m u m 3 8 VVI N H I n h i b i t ( p i n 3 ) i n p u t v o l t a g e 0 . 3 t o 5

( 1 ) S t r e s s e s b e y o n d t h o s e l i s t e d u n d e r a b s o l u t e m a x i m u m r a t i n g s m a y c a u s e p e r m a n e n t d a m a g e t o t h e d e v i c e . T h e s e a r e s t r e s s r a t i n g s o n l y , a n d f u n c t i o n a l o p e r a t i o n o f t h e d e v i c e a t t h e s e o r a n y o t h e r c o n d i t i o n s b e y o n d t h o s e i n d i c a t e d u n d e r r e c o m m e n d e d o p e r a t i n gc o n d i t i o n s i s n o t i m p l i e d . E x p o s u r e t o a b s o l u t e - m a x i m u m - r a t e d c o n d i t i o n s f o r e x t e n d e d p e r i o d s m a y a f f e c t d e v i c e r e l i a b i l i t y .

M I N M A X U N I T

P T N 7 8 0 0 0 W 7 3 6 VI I n p u t v o l t a g e V

P T N 7 8 0 0 0 H 1 5 3 6

TA O p e r a t i n g f r e e - a i r t e m p e r a t u r e 4 0 8 5 C

P T N 7 8 0 0 0 x ( S u f f i x A H , A S , a n d A Z )

W e i g h t 2 g r a m s

F l a m m a b i l i t y M e e t s U L 9 4 V - O

P e r M i l - S T D - 8 8 3 D , M e t h o d 2 0 0 2 . 3 , 1 m s , 1 / 2 s i n e , M e c h a n i c a l s h o c k 5 0 0 G ( 1 )

m o u n t e d

H o r i z o n t a l T / H ( s u f f i x A H ) 2 0 G ( 1 )

M e c h a n i c a l v i b r a t i o n M i l - S T D - 8 8 3 D , M e t h o d 2 0 0 7 . 2 , 2 0 - 2 0 0 0 H z H o r i z o n t a l S M D ( s u f f i x A S a n d A Z ) 1 5 G ( 1 )

( 1 ) Q u a l i f i c a t i o n l i m i t .

2 S u b m i t D o c u m e n t a t i o n F e e d b a c k C o p y r i g h t 2 0 0 4 2 0 0 8 , T e x a s I n s t r u m e n t s I n c o r p o r a t e d

P r o d u c t F o l d e r L i n k ( s ) : P T N 7 8 0 0 0 W P T N 7 8 0 0 0 H
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E L E C T R I C A L C H A R A C T E R I S T I C S

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H


o p e r a t i n g a t 2 5 C f r e e - a i r t e m p e r a t u r e , V I = 2 0 V , V O = 5 V , I O = IO ( m a x ) , C I = 2 . 2 F , C O = 1 0 0 F ( u n l e s s o t h e r w i s e n o t e d )

P T N 7 8 0 0 0 W P A R A M E T E R T E S T C O N D I T I O N S

M I N T Y P M A X U N I T

IO O u t p u t c u r r e n t T A = 8 5 C , n a t u r a l c o n v e c t i o n a i r f l o w 0 1 . 5 A

VI I n p u t v o l t a g e r a n g e O v e r I O r a n g e 7 ( 1 ) 3 6 ( 2 ) V

S e t - p o i n t v o l t a g e t o l e r a n c e T A = 2 5 C 2 % ( 3 )

T e m p e r a t u r e v a r i a t i o n 4 0 C t o + 8 5 C 0 . 5 %

L i n e r e g u l a t i o n O v e r V I r a n g e 1 0 m V VOL o a d r e g u l a t i o n O v e r I O r a n g e 1 0 m V

I n c l u d e s s e t p o i n t , l i n e , l o a d T o t a l o u t p u t v o l t a g e v a r i a t i o n 3 % ( 3 )

4 0 C < T A < 8 5 C

VI < 1 2 V 2 . 5 V I 2

1 2 V VI 1 5 . 1 V 2 . 5 V I 2 . 5 VO A d j O u t p u t v o l t a g e a d j u s t r a n g e V

1 5 . 1 V < V I 2 5 V 2 . 5 1 2 . 6

VI > 2 5 V 0 . 1 x V I 1 2 . 6

VI = 2 4 V , R S E T = 7 3 2 , VO = 1 2 V 9 1 %

E f f i c i e n c y V I = 1 5 V , R S E T = 2 1 k , VO = 5 V 8 6 %

VI = 1 5 V , R S E T = 7 8 . 7 k , VO = 3 . 3 V 8 2 %

O u t p u t v o l t a g e r i p p l e 2 0 M H z b a n d w i t h 1 % V O V( P P )

IO ( L I M ) C u r r e n t l i m i t t h r e s h o l d VO = 5 0 m V 3 . 2 A

1 A / s l o a d s t e p f r o m 5 0 % t o 1 0 0 % I O m a x

T r a n s i e n t r e s p o n s e R e c o v e r y t i m e 1 0 0 s

VO o v e r / u n d e r s h o o t 2 . 5 % V O

VI i n c r e a s i n g 5 . 5 U V L O U n d e r v o l t a g e l o c k o u t V

VI d e c r e a s i n g 5 . 2

I n p u t h i g h v o l t a g e ( V I H ) 1 O p e n ( 4 )

VI n h i b i t c o n t r o l ( p i n 3 ) I n p u t l o w v o l t a g e ( V I L ) 0 . 1 0 . 3

I n p u t l o w c u r r e n t ( I I L ) 0 . 2 5 m A

II ( S T B Y ) I n p u t s t a n d b y c u r r e n t P i n 3 c o n n e c t e d t o G N D 1 7 m A

FS S w i t c h i n g f r e q u e n c y O v e r V I a n d I O r a n g e s 4 4 0 5 5 0 6 6 0 k H z

CI E x t e r n a l i n p u t c a p a c i t a n c e C e r a m i c 2 . 2 ( 5 ) F

N o n c e r a m i c 1 0 0 ( 6 )

FCO E x t e r n a l o u t p u t c a p a c i t a n c e C e r a m i c 2 0 0

E q u i v . s e r i e s r e s i s t a n c e ( n o n c e r a m i c ) 1 0 ( 7 ) m

P e r T e l c o r d i a S R - 3 3 2 , 5 0 % s t r e s s , M T B F C a l c u l a t e d r e l i a b i l i t y 8 . 9 1 06 H r

TA = 4 0 C , g r o u n d b e n i g n

( 1 ) F o r o u t p u t v o l t a g e s l e s s t h a n 1 0 V , t h e m i n i m u m i n p u t v o l t a g e i s 7 V o r ( V O + 2 ) V , w h i c h e v e r i s g r e a t e r . F o r o u t p u t v o l t a g e s o f 1 0 V a n d h i g h e r , t h e m i n i m u m i n p u t v o l t a g e i s ( V O + 2 . 5 ) V . S e e t h e A p p l i c a t i o n I n f o r m a t i o n s e c t i o n f o r f u r t h e r g u i d a n c e .

( 2 ) F o r o u t p u t v o l t a g e s l e s s t h a n 3 . 6 V , t h e m a x i m u m i n p u t v o l t a g e i s 1 0 V O . S e e t h e A p p l i c a t i o n I n f o r m a t i o n s e c t i o n f o r f u r t h e r g u i d a n c e . ( 3 ) T h e s e t - p o i n t v o l t a g e t o l e r a n c e i s a f f e c t e d b y t h e t o l e r a n c e a n d s t a b i l i t y o f R S E T. T h e s t a t e d l i m i t i s u n c o n d i t i o n a l l y m e t i f R S E T h a s a

t o l e r a n c e o f 1 % w i t h w i t h 1 0 0 p p m / C o r b e t t e r t e m p e r a t u r e s t a b i l i t y . ( 4 ) T h i s c o n t r o l p i n h a s a n i n t e r n a l p u l l u p , a n d i f l e f t o p e n c i r c u i t , t h e m o d u l e o p e r a t e s w h e n i n p u t p o w e r i s a p p l i e d . T h e o p e n - c i r c u i t v o l t a g e

i s t y p i c a l l y 1 . 5 V . A s m a l , l l o w - l e a k a g e ( < 1 0 0 n A ) M O S F E T i s r e c o m m e n d e d f o r c o n t r o l . S e e t h e A p p l i c a t i o n I n f o r m a t i o n s e c t i o n f o r f u r t h e r g u i d a n c e .

( 5 ) A n e x t e r n a l 2 . 2 - F c e r a m i c c a p a c i t o r i s r e q u i r e d a c r o s s t h e i n p u t ( V I a n d G N D ) f o r p r o p e r o p e r a t i o n . L o c a t e t h e c a p a c i t o r c l o s e t o t h e m o d u l e .

( 6 ) 1 0 0 F o f o u t p u t c a p a c i t a n c e i s r e q u i r e d f o r p r o p e r o p e r a t i o n . S e e t h e A p p l i c a t i o n I n f o r m a t i o n s e c t i o n f o r f u r t h e r g u i d a n c e . ( 7 ) T h i s i s t h e t y p i c a l E S R f o r a l l t h e e l e c t r o l y t i c ( n o n c e r a m i c ) c a p a c i t a n c e . U s e 1 7 m a s t h e m i n i m u m w h e n u s i n g m a x i m u m E S R v a l u e s

t o c a l c u l a t e .

C o p y r i g h t 2 0 0 4 2 0 0 8 , T e x a s I n s t r u m e n t s I n c o r p o r a t e d S u b m i t D o c u m e n t a t i o n F e e d b a c k 3



4/26

E L E C T R I C A L C H A R A C T E R I S T I C S

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H


o p e r a t i n g a t 2 5 C f r e e - a i r t e m p e r a t u r e , V I = 2 4 V , V O = 1 2 V , I O = IO ( m a x ) , C I = 2 4 . 7 F , C O = 1 0 0 F ( u n l e s s o t h e r w i s e

n o t e d )

P T N 7 8 0 0 0 H P A R A M E T E R T E S T C O N D I T I O N S

M I N T Y P M A X U N I T

VO = 1 2 V 0 . 1 1 . 5

IO O u t p u t c u r r e n t T A = 8 5 C , n a t u r a l c o n v e c t i o n a i r f l o w V O = 1 5 V 0 . 1 1 . 5 ( 1 ) A

VO = 2 2 V 0 . 1 1 ( 1 )

VI I n p u t v o l t a g e r a n g e O v e r I O r a n g e 1 5 ( 2 ) 3 6 V

S e t - p o i n t v o l t a g e t o l e r a n c e T A = 2 5 C 2 % ( 3 )

T e m p e r a t u r e v a r i a t i o n 4 0 C t o + 8 5 C 0 . 5 %

L i n e r e g u l a t i o n O v e r V I r a n g e 1 0 m V VOL o a d r e g u l a t i o n O v e r I O r a n g e 1 0 m V

I n c l u d e s s e t p o i n t , l i n e , l o a d T o t a l o u t p u t v o l t a g e 3 % ( 3 )

v a r i a t i o n 4 0 C < T A < 8 5 C

VI < 1 9 V 1 1 . 8 5 V I 3

O u t p u t v o l t a g e a d j u s t 1 9 V VI 2 5 V 1 1 . 8 5 V I 4VO A d j Vr a n g e

VI > 2 5 V 1 1 . 8 5 2 2

VI = 2 4 V , R S E T = 3 8 3 k , VO = 1 2 V 9 1 %

E f f i c i e n c y V I = 2 4 V , R S E T = 1 5 k , VO = 1 5 V 9 3 %

VI = 3 2 V , R S E T = 9 5 . 3 , VO = 2 2 V 9 4 %

O u t p u t v o l t a g e r i p p l e 2 0 M H z b a n d w i t h 1 % V O V( P P )

IO ( L I M ) C u r r e n t l i m i t t h r e s h o l d VO = 5 0 m V , m i n i m u m V I 2 IO ( m a x ) A

1 A / s l o a d s t e p f r o m 5 0 % t o 1 0 0 % I O m a x

T r a n s i e n t r e s p o n s e R e c o v e r y t i m e 2 0 0 s

VO o v e r / u n d e r s h o o t 1 % V O

VI i n c r e a s i n g 1 2 . 2 U V L O U n d e r v o l t a g e l o c k o u t V

VI d e c r e a s i n g 1 2

I n p u t h i g h v o l t a g e ( V I H ) 1 O p e n ( 4 )

VI n h i b i t c o n t r o l ( p i n 3 ) I n p u t l o w v o l t a g e ( V I L ) 0 . 1 0 . 3

I n p u t l o w c u r r e n t ( I I L ) 0 . 2 5 m A

II ( S T B Y ) I n p u t s t a n d b y c u r r e n t P i n 3 c o n n e c t e d t o G N D 1 7 m A

FS S w i t c h i n g f r e q u e n c y O v e r V I a n d I O r a n g e s 4 4 0 5 5 0 6 6 0 k H z

CI E x t e r n a l i n p u t c a p a c i t a n c e C e r a m i c 9 . 4 ( 5 ) F

N o n c e r a m i c 1 0 0 ( 6 )

FE x t e r n a l o u t p u t CO C e r a m i c 2 0 0 c a p a c i t a n c e

E q u i v . s e r i e s r e s i s t a n c e ( n o n c e r a m i c ) 1 0 ( 7 ) m

P e r T e l c o r d i a S R - 3 3 2 , 5 0 % s t r e s s , M T B F C a l c u l a t e d r e l i a b i l i t y 8 . 9 1 06 H r

TA = 4 0 C , g r o u n d b e n i g n

( 1 ) T h e m a x i m u m o u t p u t c u r r e n t i s 1 . 5 A o r t h e m a x i m u m o u t p u t p o w e r i s 2 2 . 5 W , w h i c h e v e r i s l e s s . ( 2 ) F o r o u t p u t v o l t a g e s l e s s t h a n 1 9 V , t h e m i n i m u m i n p u t v o l t a g e i s 1 5 V o r ( V O + 3 ) V , w h i c h e v e r i s g r e a t e r . F o r o u t p u t v o l t a g e s o f 1 9 V

a n d h i g h e r , t h e m i n i m u m i n p u t v o l t a g e i s ( V O + 4 ) V . S e e t h e A p p l i c a t i o n I n f o r m a t i o n s e c t i o n f o r f u r t h e r g u i d a n c e . ( 3 ) T h e s e t - p o i n t v o l t a g e t o l e r a n c e i s a f f e c t e d b y t h e t o l e r a n c e a n d s t a b i l i t y o f R S E T. T h e s t a t e d l i m i t i s u n c o n d i t i o n a l l y m e t i f R S E T h a s a

t o l e r a n c e o f 1 % w i t h w i t h 1 0 0 p p m / C o r b e t t e r t e m p e r a t u r e s t a b i l i t y . ( 4 ) T h i s c o n t r o l p i n h a s a n i n t e r n a l p u l l u p , a n d i f l e f t o p e n c i r c u i t , t h e m o d u l e o p e r a t e s w h e n i n p u t p o w e r i s a p p l i e d . T h e o p e n - c i r c u i t v o l t a g e

i s t y p i c a l l y 1 . 5 V . A s m a l l , l o w - l e a k a g e ( < 1 0 0 n A ) M O S F E T i s r e c o m m e n d e d f o r c o n t r o l . S e e t h e A p p l i c a t i o n I n f o r m a t i o n s e c t i o n f o r f u r t h e r g u i d a n c e .

( 5 ) T w o e x t e r n a l 4 . 7 - F c e r a m i c c a p a c i t o r s a r e r e q u i r e d a c r o s s t h e i n p u t ( V I a n d G N D ) f o r p r o p e r o p e r a t i o n . L o c a t e t h e c a p a c i t o r c l o s e t o t h e m o d u l e .

( 6 ) 1 0 0 F o f o u t p u t c a p a c i t a n c e i s r e q u i r e d f o r p r o p e r o p e r a t i o n . S e e t h e A p p l i c a t i o n I n f o r m a t i o n s e c t i o n f o r f u r t h e r g u i d a n c e . ( 7 ) T h i s i s t h e t y p i c a l E S R f o r a l l t h e e l e c t r o l y t i c ( n o n c e r a m i c ) c a p a c i t a n c e . U s e 1 7 m a s t h e m i n i m u m w h e n u s i n g m a x i m u m E S R v a l u e s

t o c a l c u l a t e .




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6/26

T Y P I C A L C H A R A C T E R I S T I C S ( 7 - V I N P U T ) ( 1 ) ( 2 )

50

60

70

80

90

100

0 0.3 0.6 0.9 1.2 1.5

Efficiency%

IO Output Current A

VO = 2.5 V

VO = 5 V VO = 3.3 V

0

10

20

30

40

50

0 0.3 0.6 0.9 1.2 1.5

IO Output Current A

OutputVoltageRipplem

V

VO

PP

VO = 2.5 VVO = 3.3 V

VO = 5 V

60LFM

20

30

40

50

60

70

80

90

0 0.3 0.6 0.9 1.2 1.5

Airflow:

Natconv

IO -OutputCurrent- A

V 5VOTemperatureDerating-

C

0

0.2

0.4

0.6

0.8

1

0 0.3 0.6 0.9 1.2 1.5

PowerDissipationW

PD

IO Output Current A

VO = 2.5 V

VO = 3.3 V

VO = 5 V

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H


E F F I C I E N C Y O U T P U T V O L T A G E R I P P L E v s v s

O U T P U T C U R R E N T O U T P U T C U R R E N T

F i g u r e 1 . F i g u r e 2 .

P O W E R D I S S I P A T I O N T E M P E R A T U R E D E R A T I N G

v s v s O U T P U T C U R R E N T O U T P U T C U R R E N T

F i g u r e 3 . F i g u r e 4 .

( 1 ) T h e e l e c t r i c a l c h a r a c t e r i s t i c d a t a h a s b e e n d e v e l o p e d f r o m a c t u a l p r o d u c t s t e s t e d a t 2 5 C . T h i s d a t a i s c o n s i d e r e d t y p i c a l f o r t h e c o n v e r t e r . A p p l i e s t o F i g u r e 1 , F i g u r e 2 , a n d F i g u r e 3 .

( 2 ) T h e t e m p e r a t u r e d e r a t i n g c u r v e s r e p r e s e n t t h e c o n d i t i o n s a t w h i c h i n t e r n a l c o m p o n e n t s a r e a t o r b e l o w t h e m a n u f a c t u r e r ' s m a x i m u m o p e r a t i n g t e m p e r a t u r e s . D e r a t i n g l i m i t s a p p l y t o m o d u l e s s o l d e r e d d i r e c t l y t o a 1 0 0 m m x 1 0 0 m m d o u b l e - s i d e d P C B w i t h 2 o z . c o p p e r . F o r s u r f a c e m o u n t p a c k a g e s , m u l t i p l e v i a s ( p l a t e d t h r o u g h h o l e s ) a r e r e q u i r e d t o a d d t h e r m a l p a t h s a r o u n d t h e p o w e r p i n s . P l e a s e r e f e r t o t h e m e c h a n i c a l s p e c i f i c a t i o n f o r m o r e i n f o r m a t i o n . A p p l i e s t o F i g u r e 4 .


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7/26

T Y P I C A L C H A R A C T E R I S T I C S ( 1 5 - V I N P U T ) ( 1 ) ( 2 )

0

20

40

60

80

100

0 0.3 0.6 0.9 1.2 1.5

IO Output Current A

OutputVoltageRipplem

V

VO

PP

VO = 2.5 VVO = 3.3 V

VO = 9 V

VO = 12 VVO = 5 V

50

60

70

80

90

100

0 0.3 0.6 0.9 1.2 1.5

Efficiency%

IO Output Current A

VO = 12 V

VO = 9 V

VO = 2.5 V

VO = 5 V

VO = 3.3 V

0

0.3

0.6

0.9

1.2

1.5

0 0.3 0.6 0.9 1.2 1.5

PowerDissipationW

PD

IO Output Current A

VO = 5 V

VO = 9 V

VO = 3.3 V

VO = 2.5 V

VO = 12 V

20

30

40

50

60

70

80

90

0 0.3 0.6 0.9 1.2 1.5

200LFM

Natconv


60LFM

120LFM

TemperatureDerating-

C

V 5VO

20

30

40

50

60

70

80

90

0 0.3 0.6 0.9 1.2 1.5

Airflow:

Natconv



C

V =12VO

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H


E F F I C I E N C Y O U T P U T V O L T A G E R I P P L E P O W E R D I S S I P A T I O N v s v s v s

O U T P U T C U R R E N T O U T P U T C U R R E N T O U T P U T C U R R E N T

F i g u r e 5 . F i g u r e 6 . F i g u r e 7 .

T E M P E R A T UR E D E R A T I N G T E M P E R A T U R E D E R A T I N G


F i g u r e 8 . F i g u r e 9 .

( 1 ) T h e e l e c t r i c a l c h a r a c t e r i s t i c d a t a h a s b e e n d e v e l o p e d f r o m a c t u a l p r o d u c t s t e s t e d a t 2 5 C . T h i s d a t a i s c o n s i d e r e d t y p i c a l f o r t h e c o n v e r t e r . A p p l i e s t o F i g u r e 5 , F i g u r e 6 , a n d F i g u r e 7 .

( 2 ) T h e t e m p e r a t u r e d e r a t i n g c u r v e s r e p r e s e n t t h e c o n d i t i o n s a t w h i c h i n t e r n a l c o m p o n e n t s a r e a t o r b e l o w t h e m a n u f a c t u r e r ' s m a x i m u m o p e r a t i n g t e m p e r a t u r e s . D e r a t i n g l i m i t s a p p l y t o m o d u l e s s o l d e r e d d i r e c t l y t o a 1 0 0 - m m x 1 0 0 - m m , d o u b l e - s i d e d P C B w i t h 2 o z . c o p p e r . F o r s u r f a c e m o u n t p a c k a g e s , m u l t i p l e v i a s ( p l a t e d t h r o u g h h o l e s ) a r e r e q u i r e d t o a d d t h e r m a l p a t h s a r o u n d t h e p o w e r p i n s . P l e a s e r e f e r t o t h e m e c h a n i c a l s p e c i f i c a t i o n f o r m o r e i n f o r m a t i o n . A p p l i e s t o F i g u r e 8 a n d F i g u r e 9 .




8/26


50

60

70

80

90

100

0 0.3 0.6 0.9 1.2 1.5

Efficiency-%

I -OutputCurrent- AO

VO =15VVO =12V

VO =3.3V

VO =5V

VO =2.5V

0

20

40

60

80

100

120

140

0 0.3 0.6 0.9 1.2 1.5


V

-OutputVoltageRipple

-mV

O

PP

VO =2.5VVO =3.3V

VO =5V

VO =12V

VO =15V

0

0.5

1

1.5

2

0 0.3 0.6 0.9 1.2 1.5

P

-PowerDissipation-

W

D


VO =12V

VO =9V

VO =5V

VO =3.3V

VO =2.5V

20

30

40

50

60

70

80

90

0 0.3 0.6 0.9 1.2 1.5

IO-OutputCurrent- A

60LFM

200LFM

120LFM

V =5VO

Natconv


C

20

30

40

50

60

70

80

90

0 0.3 0.6 0.9 1.2 1.5

IO-OutputCurrent- A

200LFM

Natconv

60LFM

120LFM

V =3.3VOTemperatureDerating-

C

20

30

40

50

60

70

80

90

0 0.3 0.6 0.9 1.2 1.5IO-OutputCurrent- A

60LFM

200LFM

120LFM

V =12VO

Natconv


C

20

30

40

50

60

70

80

90

0 0.3 0.6 0.9 1.2 1.5


200LFM

Natconv

60LFM

120LFM

V =15VOTemperatureDerating-

C

20

40

50

60

70

80

90

0 0.2 0.4 0.6 0.8 1.21



C

30 V =18VO

60LFM

Natconv200LFM

120LFM

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H




F i g u r e 1 0 . F i g u r e 1 1 . F i g u r e 1 2 .

T E M P E R A T U R E D E R A T I N G T E M P E R A T U R E D E R A T I N G T E M P E R A T U R E D E R A T I N G v s v s v s



T E M P E R A T U R E D E R A T I N G T E M P E R A T U R E D E R A T I N G


F i g u r e 1 6 . F i g u r e 1 7 .

( 1 ) T h e e l e c t r i c a l c h a r a c t e r i s t i c d a t a h a s b e e n d e v e l o p e d f r o m a c t u a l p r o d u c t s t e s t e d a t 2 5 C . T h i s d a t a i s c o n s i d e r e d t y p i c a l f o r t h e c o n v e r t e r . A p p l i e s t o F i g u r e 1 0 , F i g u r e 1 1 , a n d F i g u r e 1 2 .

( 2 ) T h e t e m p e r a t u r e d e r a t i n g c u r v e s r e p r e s e n t t h e c o n d i t i o n s a t w h i c h i n t e r n a l c o m p o n e n t s a r e a t o r b e l o w t h e m a n u f a c t u r e r ' s m a x i m u m o p e r a t i n g t e m p e r a t u r e s . D e r a t i n g l i m i t s a p p l y t o m o d u l e s s o l d e r e d d i r e c t l y t o a 1 0 0 - m m x 1 0 0 - m m , d o u b l e - s i d e d P C B w i t h 2 o z . c o p p e r . F o r s u r f a c e m o u n t p a c k a g e s , m u l t i p l e v i a s ( p l a t e d t h r o u g h h o l e s ) a r e r e q u i r e d t o a d d t h e r m a l p a t h s a r o u n d t h e p o w e r p i n s . P l e a s e r e f e r t o t h e m e c h a n i c a l s p e c i f i c a t i o n f o r m o r e i n f o r m a t i o n . A p p l i e s t o F i g u r e 1 3 t h r o u g h F i g u r e 1 7 .


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9/26


0

50

100

150

200

250

0 0.3 0.6 0.9 1.2 1.5


V

-OutputVoltageRipple-

mV

O

PP V =22VO

V =12VO

V =5VO V =3.3VO

V =9VO

0

0.5

1

1.5

2

2.5

0 0.3 0.6 0.9 1.2 1.5

VO =12V

VO =5V

VO =3.3V

VO =15V

V =22VO


P

-Power

Diss

ipa

tion-

W

D

20

30

40

50

60

70

80

90

100

0 0.3 0.6 0.9 1.2 1.5

E

iciency-


V =3.3VO

V =5VO

V =12VO

V =22VO V =15VO

20

30

40

50

60

70

80

90

0 0.3 0.6 0.9 1.2 1.5

200LFM

60LFM

120LFM

V =3.3VO

Natconv



C

20

30

40

50

60

70

80

90

0 0.3 0.6 0.9 1.2 1.5

200LFM

Natconv



C

120LFM

60LFM

V =5VO

20

30

40

50

60

70

80

90

0 0.3 0.6 0.9 1.2 1.5

200LFM

Natconv


120LFM

60LFM

V =12VOTemperatureDerating-

C

20

30

40

50

60

70

80

90

0 0.2 0.60.4 0.8 1 1.2


Te

mperatureDerating-

C

V =18VO

200LFM

60LFM

120LFM

Natconv

20

30

40

50

60

70

80

90

0 0.3 0.6 0.9 1.2 1.5

200LFM

60LFM

120LFM

Natconv

V =15VO



C

0 0.2 0.4 0.6 10.8



C

V =22VO

Natconv

60LFM

120LFM

200LFM

20

30

40

50

60

70

80

90

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H





T E M P E R A T U R E D E R A T I N G T E M P E R A T U R E D E R A T I N G T E M P E R A T U R E D E R A T I N G v s v s v s



T E M P E R A T U R E D E R A T I N G T E M P E R A T U R E D E R A T I N G T E M P E R A T U R E D E R A T I N G

v s v s v s O U T P U T C U R R E N T O U T P U T C U R R E N T O U T P U T C U R R E N T


( 1 ) T h e e l e c t r i c a l c h a r a c t e r i s t i c d a t a h a s b e e n d e v e l o p e d f r o m a c t u a l p r o d u c t s t e s t e d a t 2 5 C . T h i s d a t a i s c o n s i d e r e d t y p i c a l f o r t h e c o n v e r t e r . A p p l i e s t o F i g u r e 1 8 , F i g u r e 1 9 , a n d F i g u r e 2 0 .

( 2 ) T h e t e m p e r a t u r e d e r a t i n g c u r v e s r e p r e s e n t t h e c o n d i t i o n s a t w h i c h i n t e r n a l c o m p o n e n t s a r e a t o r b e l o w t h e m a n u f a c t u r e r ' s m a x i m u m o p e r a t i n g t e m p e r a t u r e s . D e r a t i n g l i m i t s a p p l y t o m o d u l e s s o l d e r e d d i r e c t l y t o a 1 0 0 - m m x 1 0 0 - m m , d o u b l e - s i d e d P C B w i t h 2 o z . c o p p e r . F o r s u r f a c e m o u n t p a c k a g e s , m u l t i p l e v i a s ( p l a t e d t h r o u g h h o l e s ) a r e r e q u i r e d t o a d d t h e r m a l p a t h s a r o u n d t h e p o w e r p i n s . P l e a s e r e f e r t o t h e m e c h a n i c a l s p e c i f i c a t i o n f o r m o r e i n f o r m a t i o n . A p p l i e s t o F i g u r e 2 1 t h r o u g h F i g u r e 2 6 .




10/26

A P P L I C A T I O N I N F O R M A T I O N

A d j u s t i n g t h e O u t p u t V o l t a g e o f t h e P T N 7 8 0 0 0 W i d e - O u t p u t A d j u s t P o w e r M o d u l e s

G e n e r a l

R =54.9kSET

W 1.25 V

V -VO min

-RP

( 1 )

I n p u t V o l t a g e C o n s i d e r a t i o n s

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H


A r e s i s t o r m u s t b e c o n n e c t e d b e t w e e n t h e VO A d j u s t c o n t r o l ( p i n 4 ) a n d G N D ( p i n 1 ) t o s e t t h e o u t p u t v o l t a g e .

T h e a d j u s t m e n t r a n g e i s f r o m 2 . 5 V t o 1 2 . 6 V f o r P T N 7 8 0 0 0 W . T h e a d j u s t m e n t r a n g e i s f r o m 1 1 . 8 5 V t o 2 2 V f o r P T N 7 8 0 0 0 H . I f p i n 4 i s l e f t o p e n , t h e o u t p u t v o l t a g e d e f a u l t s t o t h e l o w e s t v a l u e .

T a b l e 2 g i v e s t h e p r e f e r r e d v a l u e o f t h e e x t e r n a l r e s i s t o r f o r s e v e r a l s t a n d a r d v o l t a g e s , w i t h t h e a c t u a l o u t p u t v o l t a g e t h a t t h e v a l u e p r o v i d e s . F o r o t h e r o u t p u t v o l t a g e s , t h e v a l u e o f t h e r e q u i r e d r e s i s t o r c a n b e c a l c u l a t e d u s i n g E q u a t i o n 1 , a n d t h e c o n s t a n t s f o r t h e a p p l i c a b l e p r o d u c t i n T a b l e 1 . A l t e r n a t i l v e y , R S E T c a n b e s i m p l y s e l e c t e d f r o m t h e r a n g e o f v a l u e s g i v e n i n T a b l e 3 . F i g u r e 2 7 s h o w s t h e p l a c e m e n t o f t h e r e q u i r e d r e s i s t o r .

T a b l e 1 . R S E T F o r m u l a C o n s t a n t s

P R O D U C T V M I N ( V ) R P ( k)

P T N 7 8 0 x 0 W 2 . 5 6 . 4 9 P T N 7 8 0 x 0 H 1 1 . 8 2 4 6 . 6 5

T h e P T N 7 8 0 0 0 i s a s t e p - d o w n s w i t c h i n g r e g u l a t o r . I n o r d e r t h a t t h e o u t p u t r e m a i n s i n r e g u l a t i o n , t h e i n p u t v o l t a g e m u s t e x c e e d t h e o u t p u t b y a m i n i m u m d i f f e r e n t i a l v o l t a g e . ( P l e a s e r e f e r t o t h e i n p u t v o l t a g e r a n g e r e q u i r e m e n t s i n t h e e l e c t r i c a l c h a r a c t e r i s t i c s t a b l e . )

A n o t h e r c o n s i d e r a t i o n i s t h e p u l s e w i d t h m o d u l a t i o n ( P W M ) r a n g e o f t h e r e g u l a t o r ' s i n t e r n a l c o n t r o l c i r c u i t . F o r s t a b l e o p e r a t i o n , i t s o p e r a t i n g d u t y c y c l e s h o u l d n o t b e l o w e r t h a n s o m e m i n i m u m p e r c e n t a g e . T h i s d e f i n e s t h e m a x i m u m a d v i s a b l e r a t i o b e t w e e n t h e r e g u l a t o r i n p u t a n d o u t p u t v o l t a g e m a g n i t u d e s .

A s a n e x a m p l e , f o r s a t i s f a c t o r y p e r f o r m a n c e , t h e o p e r a t i n g i n p u t v o l t a g e r a n g e o f t h e P T N 7 8 0 0 0 x m u s t a d h e r e t o t h e f o l l o w i n g r e q u i r e m e n t s .

1 . F o r P T N 7 8 0 0 0 W o u t p u t v o l t a g e s l o w e r t h a n 1 0 V , t h e m i n i m u m i n p u t v o l t a g e i s ( V O + 2 V ) o r 7 V , w h i c h e v e r i s h i g h e r .

2 . F o r P T N 7 8 0 0 0 W o u t p u t v o l t a g e s e q u a l t o 1 0 V a n d h i g h e r , t h e m i n i m u m i n p u t v o l t a g e i s ( V O + 2 . 5 V ) .

3 . F o r P T N 7 8 0 0 0 W , t h e m a x i m u m i n p u t v o l t a g e i s ( 1 0 x V O ) o r 3 6 V , w h i c h e v e r i s l e s s .

4 . F o r P T N 7 8 0 0 0 H o u t p u t v o l t a g e s l o w e r t h a n 1 9 V , t h e m i n i m u m i n p u t v o l t a g e i s ( V O + 3 V ) o r 1 5 V , w h i c h e v e r i s h i g h e r .

5 . F o r P T N 7 8 0 0 0 H o u t p u t v o l t a g e s e q u a l t o 1 9 V a n d h i g h e r , t h e m i n i m u m i n p u t v o l t a g e i s ( V O + 4 V ) .

1 0 S u b m i t D o c u m e n t a t i o n F e e d b a c k C o p y r i g h t 2 0 0 4 2 0 0 8 , T e x a s I n s t r u m e n t s I n c o r p o r a t e d



11/26

Inhibit

GND GND

RSET

0.05 W

1%

CI

(Ceramic)

CO

(Required)

PTN78000W

1 4

52

3AdjGND

VOVI

2.2 Fm 100 Fm

VI VO

Inh

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H


A s a n e x a m p l e , T a b l e 2 g i v e s t h e o p e r a t i n g i n p u t v o l t a g e r a n g e f o r t h e c o m m o n o u t p u t b u s v o l t a g e s . I n a d d i t i o n , t h e E l e c t r i c a l C h a r a c t e r i s t i c s d e f i n e t h e a v a i l a b l e o u t p u t v o l t a g e a d j u s t r a n g e f o r v a r i o u s i n p u t v o l t a g e s .

T a b l e 2 . S t a n d a r d V a l u e s o f R S E T f o r C o m m o n O u t p u t V o l t a g e s

RS E TVO VO O p e r a t i n g P R O D U C T ( S t a n d a r d V a l u e ) ( R e q u i r e d ) ( V ) ( A c t u a l ) ( V ) V I R a n g e ( V ) ( k)

2 . 5 O p e n 2 . 5 7 t o 2 5

3 . 3 7 8 . 7 3 . 3 0 6 7 t o 3 3 P T N 7 8 0 x 0 W

5 2 1 4 . 9 9 6 7 t o 3 6

1 2 0 . 7 3 2 1 2 . 0 0 2 1 4 . 5 t o 3 6

1 2 3 8 3 1 2 . 0 0 0 1 5 t o 3 6

1 5 1 5 1 4 . 9 9 4 1 8 t o 3 6 P T N 7 8 0 x 0 H

1 8 4 . 4 2 1 8 . 0 2 3 2 1 t o 3 6

2 2 0 . 0 9 5 3 2 1 . 9 9 8 2 6 t o 3 6

( 1 ) A 0 . 0 5 - W r a t e d r e s i s t o r m a y b e u s e d . T h e t o l e r a n c e s h o u l d b e 1 % , w i t h a t e m p e r a t u r e s t a b i l i t y o f 1 0 0 p p m / C ( o r

b e t t e r ) . P l a c e t h e r e s i s t o r a s c l o s e t o t h e r e g u l a t o r a s p o s s i b l e . C o n n e c t t h e r e s i s t o r d i r e c t l y b e t w e e n p i n s 4 a n d 1

u s i n g d e d i c a t e d P C B t r a c e s .

( 2 ) N e v e r c o n n e c t c a p a c i t o r s f r o m VO A d j u s t t o G N D o r VO. A n y c a p a c i t a n c e a d d e d t o t h e VO A d j u s t p i n a f f e c t s t h e s t a b i l i t y o f t h e r e g u l a t o r .

F i g u r e 2 7 . P T N 7 8 0 0 0 W V O A d j u s t R e s i s t o r P l a c e m e n t

C o p y r i g h t 2 0 0 4 2 0 0 8 , T e x a s I n s t r u m e n t s I n c o r p o r a t e d S u b m i t D o c u m e n t a t i o n F e e d b a c k 1 1



12/26

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H


T a b l e 3 . P T N 7 8 0 0 0 W O u t p u t V o l t a g e S e t - P o i n t R e s i s t o r V a l u e s

VO ( V ) R S E T ( k) VO ( V ) R S E T ( k) VO ( V ) R S E T ( k) VO ( V ) R S E T ( k)

2 . 5 0 O p e n 3 . 7 5 0 . 7 6 . 1 1 2 . 6 9 . 0 4 . 0 7

2 . 5 5 1 3 7 0 3 . 8 4 6 . 3 6 . 2 1 2 . 1 9 . 2 3 . 7 5

2 . 6 0 6 8 0 3 . 9 4 2 . 5 6 . 3 1 1 . 6 9 . 4 3 . 4 6

2 . 6 5 4 5 1 4 . 0 3 9 . 3 6 . 4 1 1 . 1 9 . 6 3 . 1 8

2 . 7 0 3 3 7 4 . 1 3 6 . 4 6 . 5 1 0 . 7 9 . 8 2 . 9 1

2 . 7 5 2 6 8 4 . 2 3 3 . 9 6 . 6 1 0 . 2 1 0 . 0 2 . 6 6

2 . 8 0 2 2 2 4 . 3 3 1 . 6 6 . 7 9 . 8 5 1 0 . 2 2 . 4 2

2 . 8 5 1 9 0 4 . 4 2 9 . 6 6 . 8 9 . 4 7 1 0 . 4 2 . 2 0

2 . 9 0 1 6 5 4 . 5 2 7 . 8 6 . 9 9 . 1 1 1 0 . 6 1 . 9 8

2 . 9 5 1 4 6 4 . 6 2 6 . 2 7 . 0 8 . 7 6 1 0 . 8 1 . 7 8

3 . 0 0 1 3 1 4 . 7 2 4 . 7 7 . 1 8 . 4 3 1 1 . 0 1 . 5 8

3 . 0 5 1 1 8 4 . 8 2 3 . 3 7 . 2 8 . 1 1 1 1 . 2 1 . 4 0

3 . 1 0 1 0 8 4 . 9 2 2 . 1 7 . 3 7 . 8 1 1 1 . 4 1 . 2 2

3 . 1 5 9 9 . 1 5 . 0 2 1 . 0 7 . 4 7 . 5 2 1 1 . 6 1 . 0 5

3 . 2 0 9 1 . 5 5 . 1 1 9 . 9 7 . 5 7 . 2 4 1 1 . 8 0 . 8 8 9

3 . 2 5 8 5 . 0 5 . 2 1 8 . 9 7 . 6 6 . 9 7 1 2 . 0 0 . 7 3 4

3 . 3 0 7 9 . 3 5 . 3 1 8 . 0 7 . 7 6 . 7 1 1 2 . 2 0 . 5 8 5

3 . 3 5 7 4 . 2 5 . 4 1 7 . 2 7 . 8 6 . 4 6 1 2 . 4 0 . 4 4 2

3 . 4 0 6 9 . 8 5 . 5 1 6 . 4 7 . 9 6 . 2 2 1 2 . 6 0 . 3 0 5

3 . 4 5 6 5 . 7 5 . 6 1 5 . 6 8 . 0 5 . 9 9

3 . 5 0 6 2 . 1 5 . 7 1 5 . 0 8 . 2 5 . 5 5

3 . 5 5 5 8 . 9 5 . 8 1 4 . 3 8 . 4 5 . 1 4

3 . 6 0 5 5 . 9 5 . 9 1 3 . 7 8 . 6 4 . 7 6

3 . 6 5 5 3 . 2 6 . 0 1 3 . 1 8 . 8 4 . 4 0




13/26

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H


T a b l e 4 . P T N 7 8 0 0 0 H O u t p u t V o l t a g e S e t - P o i n t R e s i s t o r V a l u e s

VO ( V ) R S E T ( k) VO ( V ) R S E T ( k) VO ( V ) R S E T ( k)

1 1 . 8 5 2 6 3 3 1 3 . 5 0 3 4 . 3 1 7 . 2 0 6 . 1 2

1 1 . 9 0 8 9 6 1 3 . 6 5 3 0 . 9 1 7 . 4 0 5 . 6 6

1 1 . 9 5 5 3 8 1 3 . 8 0 2 8 . 1 1 7 . 6 0 5 . 2 3

1 2 . 0 0 3 8 3 1 3 . 9 5 2 5 . 6 1 7 . 8 0 4 . 8 3

1 2 . 1 0 2 4 2 1 4 . 1 0 2 3 . 5 1 8 . 0 0 4 . 4 6

1 2 . 1 5 2 0 4 1 4 . 2 5 2 1 . 6 1 8 . 2 0 4 . 1 1

1 2 . 2 0 1 7 6 1 4 . 4 0 1 9 . 9 1 8 . 4 0 3 . 7 9

1 2 . 2 5 1 5 4 1 4 . 5 5 1 8 . 5 1 8 . 6 0 3 . 4 8

1 2 . 3 0 1 3 8 1 4 . 7 0 1 7 . 2 1 8 . 8 0 3 . 1 9

1 2 . 3 5 1 2 4 1 4 . 8 5 1 6 . 0 1 9 . 0 0 2 . 9 1

1 2 . 4 0 1 1 3 1 5 . 0 0 1 4 . 9 1 9 . 2 0 2 . 6 5

1 2 . 4 5 1 0 3 1 5 . 1 5 1 3 . 9 1 9 . 4 0 2 . 4 1

1 2 . 5 0 9 4 . 9 1 5 . 3 0 1 3 . 1 1 9 . 6 0 2 . 1 8

1 2 . 5 5 8 7 . 9 1 5 . 4 5 1 2 . 3 1 9 . 8 0 1 . 9 5

1 2 . 6 0 8 1 . 8 1 5 . 6 0 1 1 . 5 2 0 . 0 0 1 . 7 4

1 2 . 6 5 7 6 . 4 1 5 . 7 5 1 0 . 8 2 0 . 2 0 1 . 5 4

1 2 . 7 0 7 1 . 7 1 5 . 9 0 1 0 . 2 2 0 . 4 0 1 . 3 5

1 2 . 7 5 6 7 . 5 1 6 . 0 5 9 . 5 9 2 0 . 6 0 1 . 1 7

1 2 . 8 0 6 3 . 7 1 6 . 2 0 9 . 0 3 2 0 . 8 0 0 . 9 9 5

1 2 . 8 5 6 0 . 2 1 6 . 3 5 8 . 5 1 2 1 . 0 0 0 . 8 2 9

1 2 . 9 0 5 7 . 1 1 6 . 5 0 8 . 0 3 2 1 . 2 0 0 . 6 6 9

1 2 . 9 5 5 4 . 3 1 6 . 6 5 7 . 5 7 2 1 . 4 0 0 . 5 1 6

1 3 . 0 0 5 1 . 7 1 6 . 8 0 7 . 1 4 2 1 . 8 0 0 . 2 2 9

1 3 . 0 5 4 9 . 3 1 7 . 1 0 6 . 3 6 2 2 . 0 0 0 . 0 9

C o p y r i g h t 2 0 0 4 2 0 0 8 , T e x a s I n s t r u m e n t s I n c o r p o r a t e d S u b m i t D o c u m e n t a t i o n F e e d b a c k 1 3



14/26

C A P A C I T O R R E C O M M E N D A T I O N S F O R P T N 7 8 0 0 0 W I D E - O U T P U T

P T N 7 8 0 0 0 W I n p u t C a p a c i t o r

P T N 7 8 0 0 0 H I n p u t C a p a c i t o r

P T N 7 8 0 0 0 W a n d P T N 7 8 0 0 0 H O u t p u t C a p a c i t o r s

C e r a m i c C a p a c i t o r s

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H


A D J U S T P O W E R M O D U L E S

T h e m i n i m u m r e q u i r e m e n t f o r t h e i n p u t o f P T N 7 8 0 0 0 W i s 2 . 2 F o f c e r a m i c c a p a c i t a n c e . T h e d i e l e c t r i c m a y b e e i t h e r a n X 5 R o r X 7 R t e m p e r a t u r e c h a r a c t e r i s t i c . C e r a m i c c a p a c i t o r s s h o u l d b e l o c a t e d w i t h i n 0 . 5 i n c h ( 1 , 2 7 c m )

o f t h e r e g u l a t o r i n p u t p i n s . E l e c t r o l y t i c c a p a c i t o r s c a n b e u s e d a t t h e i n p u t , b u t o n l y i n a d d i t i o n t o t h e r e q u i r e d c e r a m i c c a p a c i t a n c e . T h e m i n i m u m r i p p l e c u r r e n t r a t i n g f o r a n y n o n c e r a m i c c a p a c i t a n c e m u s t b e a t l e a s t 6 5 0 m A r m s . T h e r i p p l e c u r r e n t r a t i n g o f e l e c t r o l y t i c c a p a c i t o r s i s a m a j o r c o n s i d e r a t i o n w h e n t h e y a r e u s e d a t t h e i n p u t . T h i s r i p p l e c u r r e n t r e q u i r e m e n t c a n b e r e d u c e d b y p l a c i n g m o r e c e r a m i c c a p a c i t o r s a t t h e i n p u t , i n a d d i t i o n t o t h e m i n i m u m r e q u i r e d c a p a c i t a n c e .

T a n t a l u m c a p a c i t o r s a r e n o t r e c o m m e n de d f o r u s e a t t h e i n p u t b u s , a s n o n e w e r e f o u n d t o m e e t t h e m i n i m u m v o l t a g e r a t i n g o f 2 x ( m a x i m u m d c v o l t a g e + a c r i p p l e ) . T h e 2 x r a t i n g i s s t a n d a r d p r a c t i c e f o r r e g u l a r t a n t a l u m c a p a c i t o r s t o e n s u r e r e l i a b i l i t y . P o l y m e r - t a n t a l u m c a p a c i t o r s a r e m o r e r e l i a b l e a n d a r e a v a i l a b l e w i t h a m a x i m u m r a t i n g o f t y p i c a l l y 2 0 V . T h e s e c a n b e u s e d w i t h i n p u t v o l t a g e s u p t o 1 6 V .

T h e m i n i m u m r e q u i r e m e n t f o r t h e i n p u t o f P T N 7 8 0 0 0 H i s 2 4 . 7 F o f c e r a m i c c a p a c i t a n c e . T h e d i e l e c t r i c m a y b e e i t h e r a n X 5 R o r X 7 R t e m p e r a t u r e c h a r a c t e r i s t i c . C e r a m i c c a p a c i t o r s s h o u l d b e l o c a t e d w i t h i n 0 . 5 i n c h ( 1 , 2 7 c m ) o f t h e r e g u l a t o r i n p u t p i n s . E l e c t r o l y t i c c a p a c i t o r s c a n b e u s e d a t t h e i n p u t , b u t o n l y i n a d d i t i o n t o t h e r e q u i r e d c e r a m i c c a p a c i t a n c e . T h e m i n i m u m r i p p l e c u r r e n t r a t i n g f o r a n y n o n c e r a m i c c a p a c i t a n c e m u s t b e a t l e a s t 3 5 0 m A r m s . T h e r i p p l e c u r r e n t r a t i n g o f e l e c t r o l y t i c c a p a c i t o r s i s a m a j o r c o n s i d e r a t i o n w h e n t h e y a r e u s e d a t t h e i n p u t . T h i s r i p p l e c u r r e n t r e q u i r e m e n t c a n b e r e d u c e d b y p l a c i n g m o r e c e r a m i c c a p a c i t o r s a t t h e i n p u t , i n a d d i t i o n t o t h e m i n i m u m r e q u i r e d c a p a c i t a n c e .

T a n t a l u m c a p a c i t o r s a r e n o t r e c o m m e n d e d f o r u s e a t t h e i n p u t b u s , a s n o n e w e r e f o u n d t o m e e t t h e m i n i m u m v o l t a g e r a t i n g o f 2 x ( m a x i m u m d c v o l t a g e + a c r i p p l e ) . T h e 2 r a t i n g i s s t a n d a r d p r a c t i c e f o r r e g u l a r t a n t a l u m c a p a c i t o r s t o e n s u r e r e l i a b i l i t y . P o l y m e r - t a n t a l u m c a p a c i t o r s a r e m o r e r e l i a b l e a n d a r e a v a i l a b l e w i t h a m a x i m u m r a t i n g o f t y p i c a l l y 2 0 V . T h e s e c a n b e u s e d w i t h i n p u t v o l t a g e s u p t o 1 6 V .

T h e m i n i m u m c a p a c i t a n c e r e q u i r e d t o i n s u r e s t a b i l i t y i s a 1 0 0 F . E i t h e r c e r a m i c o r e l e c t r o l y t i c - t y p e c a p a c i t o r s

c a n b e u s e d . T h e m i n i m u m r i p p l e c u r r e n t r a t i n g f o r t h e n o n c e r a m i c c a p a c i t a n c e m u s t b e a t l e a s t 1 5 0 m A r m s . T h e s t a b i l i t y o f t h e m o d u l e a n d v o l t a g e t o l e r a n c e s w i l l b e c o m p r o m i s e d i f t h e c a p a c i t o r i s n o t p l a c e d n e a r t h e o u t p u t b u s p i n s . A h i g h - q u a l i t y , c o m p u t e r - g r a d e e l e c t r o l y t i c c a p a c i t o r s h o u l d b e a d e q u a t e . A c e r a m i c c a p a c i t o r c a n b e a l s o b e l o c a t e d w i t h i n 0 . 5 i n c h ( 1 , 2 7 c m ) o f t h e o u t p u t p i n .

F o r a p p l i c a t i o n s w i t h l o a d t r a n s i e n t s ( s u d d e n c h a n g e s i n l o a d c u r r e n t ) , t h e r e g u l a t o r r e s p o n s e i m p r o v e s w i t h a d d i t i o n a l c a p a c i t a n c e . A d d i t i o n a l e l e c t r o l y t i c c a p a c i t o r s s h o u l d b e l o c a t e d c l o s e t o t h e l o a d c i r c u i t . T h e s e c a p a c i t o r s p r o v i d e d e c o u p l i n g o v e r t h e f r e q u e n c y r a n g e , 2 k H z t o 1 5 0 k H z . A l u m i n u m e l e c t r o l y t i c c a p a c i t o r s a r e s u i t a b l e f o r a m b i e n t t e m p e r a t u r e s a b o v e 0 C . F o r o p e r a t i o n b e l o w 0 C , t a n t a l u m o r O S - C O N t y p e c a p a c i t o r s a r e r e c o m m e n d e d . W h e n u s i n g o n e o r m o r e n o n c e r a m i c c a p a c i t o r s , t h e c a l c u l a t e d e q u i v a l e n t E S R s h o u l d b e n o l o w e r t h a n 1 0 m ( 1 7 m u s i n g t h e m a n u f a c t u r e r ' s m a x i m u m E S R f o r a s i n g l e c a p a c i t o r ) . A l i s t o f c a p a c i t o r s a n d v e n d o r s a r e i d e n t i f i e d i n T a b l e 5 a n d T a b l e 6 , t h e r e c o m m e n d e d c a p a c i t o r t a b l e s .

A b o v e 1 5 0 k H z t h e p e r f o r m a n c e o f a l u m i n u m e l e c t r o l y t i c c a p a c i t o r s b e c o m e s l e s s e f f e c t i v e . T o f u r t h e r r e d u c e t h e r e f l e c t e d i n p u t r i p p l e c u r r e n t , o r t h e o u t p u t t r a n s i e n t r e s p o n s e , m u l t i l a y e r c e r a m i c c a p a c i t o r s m u s t b e a d d e d . C e r a m i c c a p a c i t o r s h a v e l o w E S R a n d t h e i r r e s o n a n t f r e q u e n c y i s h i g h e r t h a n t h e b a n d w i d t h o f t h e r e g u l a t o r . W h e n p l a c e d a t t h e o u t p u t , t h e i r c o m b i n e d E S R i s n o t c r i t i c a l a s l o n g a s t h e t o t a l v a l u e o f c e r a m i c c a p a c i t a n c e d o e s n o t e x c e e d 2 0 0 F .




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T a n t a l u m C a p a c i t o r s

C a p a c i t o r T a b l e

D e s i g n i n g f o r L o a d T r a n s i e n t s

P T N 7 8 0 0 0 W , P T N 7 8 0 0 0 H


T a n t a l u m t y p e c a p a c i t o r s m a y b e u s e d a t t h e o u t p u t , a n d a r e r e c o m m e n d e d f o r a p p l i c a t i o n s w h e r e t h e a m b i e n t o p e r a t i n g t e m p e r a t u r e c a n b e l e s s t h a n 0 C . T h e A V X T P S , S p r a g u e 5 9 3 D / 5 9 4 / 5 9 5 , a n d K e m e t T 4 9 5 / T 5 1 0 / T 5 2 0 c a p a c i t o r s s e r i e s a r e s u g g e s t e d o v e r m a n y o t h e r t a n t a l u m t y p e s d u e t o t h e i r r a t e d s u r g e , p o w e r d i s s i p a t i o n , a n d r i p p l e c u r r e n t c a p a b i l i t y . A s a c a u t i o n , m a n y g e n e r a l - p u r p o s e t a n t a l u m c a p a c i t o r s h a v e c o n s i d e r a b l y h i g h e r E S R , r e d u c e d p o w e r d i s s i p a t i o n , a n d l o w e r r i p p l e c u r r e n t c a p a b i l i t y . T h e s e c a p a c i t o r s a r e

a l s o l e s s r e l i a b l e a s t h e y h a v e l o w e r p o w e r d i s s i p a t i o n a n d s u r g e c u r r e n t r a t i n g s . T a n t a l u m c a p a c i t o r s t h a t d o n o t h a v e a s t a t e d E S R o r s u r g e c u r r e n t r a t i n g a r e n o t r e c o m m e n d e d f o r p o w e r a p p l i c a t i o n s . W h e n s p e c i f y i n g O S - C O N a n d p o l y m e r t a n t a l u m c a p a c i t o r s f o r t h e o u t p u t , t h e m i n i m u m E S R l i m i t i s e n c o u n t e r e d w e l l b e f o r e t h e m a x i m u m c a p a c i t a n c e v a l u e i s r e a c h e d .

T h e c a p a c i t o r t a b l e , T a b l e 5 a n d T a b l e 6 , i d e n t i f i e s t h e c h a r a c t e r i s t i c s o f c a p a c i t o r s f r o m v a r i o u s v e n d o r s w i t h a c c e p t a b l e E S R a n d r i p p l e c u r r e n t ( r m s ) r a t i n g s . T h e r e c o m m e n d e d n u m b e r o f c a p a c i t o r s r e q u i r e d a t b o t h t h e i n p u t a n d o u t p u t b u s e s i s i d e

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