![]() |
|
If you can't view the Datasheet, Please click here to try to view without PDF Reader . |
|
Datasheet File OCR Text: |
c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 1 a n p e c r e s e r v e s t h e r i g h t t o m a k e c h a n g e s t o i m p r o v e r e l i a b i l i t y o r m a n u f a c t u r a b i l i t y w i t h o u t n o t i c e , a n d a d v i s e c u s t o m e r s t o o b t a i n t h e l a t e s t v e r s i o n o f r e l e v a n t i n f o r m a t i o n t o v e r i f y b e f o r e p l a c i n g o r d e r s . 3 a , 2 0 v , 3 8 0 k h z , s y n c h r o n o u s s t e p - d o w n c o n v e r t e r f e a t u r e s w i d e i n p u t v o l t a g e f r o m 4 . 7 5 v t o 2 0 v o u t p u t c u r r e n t u p t o 3 a a d j u s t a b l e o u t p u t v o l t a g e f r o m 0 . 8 v t o 9 0 % v i n - 0 . 8 v r e f e r e n c e v o l t a g e - 2 . 5 % s y s t e m a c c u r a c y 8 0 m w i n t e g r a t e d m o s f e t s h i g h e f f i c i e n c y u p t o 9 3 % c u r r e n t - m o d e o p e r a t i o n - s t a b l e w i t h c e r a m i c o u t p u t c a p a c i t o r s - f a s t t r a n s i e n t r e s p o n s e p o w e r - o n - r e s e t m o n i t o r i n g f i x e d 3 8 0 k h z s w i t c h i n g f r e q u e n c y i n p w m m o d e automatic pulse-skipping mode (psm)/pwm mode operation (APW7070A) forced-pwm operation (apw7070) b u i l t - i n d i g i t a l s o f t - s t a r t o u t p u t c u r r e n t - l i m i t p r o t e c t i o n w i t h f r e q u e n c y f o l d b a c k 7 0 % u n d e r - v o l t a g e p r o t e c t i o n o v e r - t e m p e r a t u r e p r o t e c t i o n 1 1 8 % o v e r - v o l t a g e p r o t e c t i o n < 5 m a q u i e s c e n t c u r r e n t d u r i n g s h u t d o w n t h e r m a l - e n h a n c e d s o p - 8 p p a c k a g e pb-free available as an option lead free and green devices available (rohs compliant) a p p l i c a t i o n s g e n e r a l d e s c r i p t i o n t h e a p w 7 0 7 0 / a i s a 3 a , s y n c h r o n o u s , s t e p - d o w n c o n - v e r t e r w i t h i n t e g r a t e d 8 0 m w m o s f e t s . t h e d e v i c e , w i t h c u r r e n t - m o d e c o n t r o l s c h e m e , c a n c o n v e r t 4 . 7 5 ~ 2 0 v i n - p u t v o l t a g e t o t h e o u t p u t v o l t a g e a d j u s t a b l e f r o m 0 . 8 t o 9 0 % v i n t o p r o v i d e e x c e l l e n t o u t p u t v o l t a g e r e g u l a t i o n . t h e a p w 7 0 7 0 a r e g u l a t e s t h e o u t p u t v o l t a g e i n a n a u t o - m a t i c p s m / p w m m o d e o p e r a t i o n , d e p e n d i n g o n t h e o u t - p u t c u r r e n t , f o r h i g h e f f i c i e n c y o p e r a t i o n o v e r l i g h t t o f u l l l o a d c u r r e n t . the apw7070 always works in a forced- pwm mode with constant frequency over full output cur- rent range for low-noise requirements. t h e a p w 7 0 7 0 / a i s a l s o e q u i p p e d w i t h p o w e r - o n - r e s e t , s o f t - s t a r t a n d w h o l e p r o t e c t i o n s ( i n c l u d i n g o v e r - v o l t a g e , u n d e r - v o l t a g e , o v e r - t e m p e r a t u r e a n d c u r r e n t - l i m i t ) i n a s i n g l e p a c k a g e . i n s h u t - d o w n m o d e , t h e s u p p l y c u r r e n t d r o p s b e l o w 5 m a . t h i s d e v i c e , a v a i l a b l e i n a n 8 - p i n s o p - 8 p p a c k a g e , p r o - v i d e s a v e r y c o m p a c t s y s t e m s o l u t i o n w i t h m i n i m a l e x t e r - n a l c o m p o n e n t s a n d g o o d t h e r m a l c o n d u c t a n c e . lcd monitor / tv settop box portable dvd wireless lan adsl, switch hub notebook computer step-down converters requiring high e f f i c i e n c y a n d 3 a o u t p u t c u r r e n t efficiency (%) o u t p u t c u r r e n t , i o u t ( a ) t y p i c a l e f f i c i e n c y 10 20 30 40 50 60 70 80 90 100 0.001 0.01 0.1 1 10 v v out =5v v out = 3.3v APW7070A free datasheet http://www.datasheetlist.com/
c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 2 o r d e r i n g a n d m a r k i n g i n f o r m a t i o n p i n c o n f i g u r a t i o n t h e p i n 5 m u s t b e c o n n e c t e d t o t h e e x p o s e d p a d symbol parameter rating unit v in vin supply voltage (vin to gnd) - 0.3 ~ 24 v > 100n s - 1 ~ v in + 0.3 v lx lx to gnd voltage < 100n s - 5 ~ v in + 6 v v in > 6.2v - 0.3 ~ 6.5 v cc vcc supply voltage (vcc to gnd) v in 6.2v v in +0.3 v v ugnd_gnd ugnd to gnd voltage - 0.3 ~ v in +0.3 v v vin_ugnd vin to ugnd voltage - 0.3 ~ 6.5v v en to gnd voltage 20 v fb, comp to gnd voltage - 0.3 ~ v cc +0.3 v maximum junction temperature 150 o c a b s o l u t e m a x i m u m r a t i n g s ( n o t e 1 ) s i m p l i f i e d a p p l i c a t i o n c i r c u i t n o t e : a n p e c l e a d - f r e e p r o d u c t s c o n t a i n m o l d i n g c o m p o u n d s / d i e a t t a c h m a t e r i a l s a n d 1 0 0 % m a t t e t i n p l a t e t e r m i n a t i o n f i n i s h ; w h i c h a r e f u l l y c o m p l i a n t w i t h r o h s . a n p e c l e a d - f r e e p r o d u c t s m e e t o r e x c e e d t h e l e a d - f r e e r e q u i r e m e n t s o f i p c / j e d e c j - s t d - 0 2 0 d f o r m s l c l a s s i f i c a t i o n a t l e a d - f r e e p e a k r e f l o w t e m p e r a t u r e . a n p e c d e f i n e s ? g r e e n ? t o m e a n l e a d - f r e e ( r o h s c o m p l i a n t ) a n d h a l o g e n f r e e ( b r o r c l d o e s n o t e x c e e d 9 0 0 p p m b y w e i g h t i n h o m o g e n e o u s m a t e r i a l a n d t o t a l o f b r a n d c l d o e s n o t e x c e e d 1 5 0 0 p p m b y w e i g h t ) . apw7070 handling code temperature range package code package code ka : sop-8p operating ambient temperature range i : -40 to 85 o c h andling code tr : tape & reel assembly material g : h a l o g e n a n d l e a d f r e e d e v i c e assembly material apw7070 ka : apw7070 xxxxx xxxxx - date code APW7070A APW7070A ka : APW7070A xxxxx xxxxx - date code gnd fb comp lx vin en ugnd vcc 9 lx 8 7 6 5 1 2 3 4 sop-8p (top view) r2 1% lx en vin gnd comp u1 apw7070/a fb ugnd v out +3.3v l1 3a vcc c3 c2 v in +12 c1 10 m f c5 r4 c6 c4 22 m f r1 1% v in c7 (optional) free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 3 symbol parameter rating unit t stg storage temperature - 65 ~ 150 o c t sdr maximum lead soldering temperature, 10 seconds 260 o c a b s o l u t e m a x i m u m r a t i n g s ( c o n t . ) ( n o t e 1 ) t h e r m a l c h a r a c t e r i s t i c s symbol parameter typical value unit q ja junction - to - ambient resistance in f ree a ir (note 2) sop - 8p 50 o c/w q jc junction - to - case resistance in f ree a ir (note 3) sop - 8p 10 o c/w n o t e 2 : q j a i s m e a s u r e d w i t h t h e c o m p o n e n t m o u n t e d o n a h i g h e f f e c t i v e t h e r m a l c o n d u c t i v i t y t e s t b o a r d i n f r e e a i r . t h e e x p o s e d p a d o f s o p - 8 p i s s o l d e r e d d i r e c t l y o n t h e p c b . n o t e 3 : t h e c a s e t e m p e r a t u r e i s m e a s u r e d a t t h e c e n t e r o f t h e e x p o s e d p a d o n t h e u n d e r s i d e o f t h e s o p - 8 p p a c k a g e . n o t e 1 : a b s o l u t e m a x i m u m r a t i n g s a r e t h o s e v a l u e s b e y o n d w h i c h t h e l i f e o f a d e v i c e m a y b e i m p a i r 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 i n g 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 . 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 ( n o t e 4 ) symbol parameter range unit v in vin supply voltage 4.75 ~ 20 v vcc supply voltage 4.0 ~ 5.5 v v out converter output voltage 0.8 ~ 90% v in v i out converter output current 0 ~ 3 a vcc input capacitor 0.22 ~ 2.2 m f vin - to - ugnd input capacitor 0 .22 ~ 2.2 m f t a ambient temperature - 40 ~ 85 o c t j junction temperature - 40 ~ 125 o c n o t e 4 : r e f e r t o t h e t y p i c a l a p p l i c a t i o n c i r c u i t s . 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 apw70 70/a symbol parameter test conditions min . typ . max . unit supply current i vin vin supply current v fb = 0.85v, v en = 3v, lx = open - 1.0 2.0 ma i vin_sd vin shutdown supply current v en = 0v , v in = 20v - - 5 m a i vcc vcc supply current v en = 3v, v cc = 5.0v - 0.7 - ma i vcc_sd vcc shutdown supply current v en = 0v, v cc = 5.0v - - 1 m a vcc 4.2v linear regulator output voltage v in = 5.2 ~ 20 v, i o = 0 ~ 8ma 4.0 4.2 4.5 v load regulation i o = 0 ~ 8ma - 6 0 - 40 0 mv r e f e r t o t h e t y p i c a l a p p l i c a t i o n c i r c u i t s . t h e s e s p e c i f i c a t i o n s a p p l y o v e r v i n = 1 2 v , v o u t = 3 . 3 v a n d t a = - 4 0 ~ 8 5 o c , u n l e s s o t h e r w i s e s p e c i f i e d . v c c i s r e g u l a t e d b y a n i n t e r n a l r e g u l a t o r . t y p i c a l v a l u e s a r e a t t a = 2 5 o c . free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 4 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 ( c o n t . ) r e f e r t o t h e t y p i c a l a p p l i c a t i o n c i r c u i t s . t h e s e s p e c i f i c a t i o n s a p p l y o v e r v i n = 1 2 v , v o u t = 3 . 3 v a n d t a = - 4 0 ~ 8 5 o c , u n l e s s o t h e r w i s e s p e c i f i e d . v c c i s r e g u l a t e d b y a n i n t e r n a l r e g u l a t o r . t y p i c a l v a l u e s a r e a t t a = 2 5 o c . apw70 70/a symbol parameter test conditions min . typ . max . unit vcc 4.2v linear regulator (cont.) current - limit v cc > por threshold 8 - 3 0 ma vin - to - ugnd 5.5v linear regulator output voltage (v vin - ugnd ) v in = 6.2 ~ 20 v, i o = 0 ~ 10ma 5.3 5.5 5.7 v load regulation i o = 0 ~ 10ma - 8 0 - 60 0 mv current - limit v in = 6.2 ~ 20 v 10 - 30 ma power - on - reset (por) and lockout voltage thresholds vcc por voltage threshold v cc r ising 3.7 3.9 4.1 v vcc por hysteresis - 0.15 - v en lockout vo ltage threshold v en r ising 2.4 2.5 2.6 v en lockout hysteresis - 0.2 - v vin - to - ugnd lockout voltage threshold v vin - ugnd r ising - 3.5 - v vin - to - ugnd lockout hysteresis - 0.2 - v reference voltage v ref reference voltage - 0.8 - v t j = 25 o c, i out =0a, v in =12v - 0.4 - +1.6 out put voltage accuracy t j = - 40 ~ 125 o c, i out = 0 ~ 3 a, v in = 4.75 ~ 20 v - 2. 5 - +2. 5 % line regulation v in = 4.75v to 20 v, i out = 0a - 0. 1 - % i out < 1 a - - 0.3 - l oad reg ulation i out = 1 ~ 3 a - - 0.53 - % /a oscillator and duty f osc oscillator running frequency v in = 4.75 ~ 20 v 340 380 420 khz foldback frequency v fb = 0v - 80 - khz maximum converter?s duty cycle - 93 - % minimum pulse width of lx v in = 4.75 ~ 20 v - 200 - ns current - mode pwm c onverter gm error amplifier transconductance - 4 00 - m a/v error amplifier dc gain comp = open 60 80 - db current - sense resistance - 0. 12 - w high - side switch r esistance between vin and exposed pad, t j = 25 o c - 80 100 m w low - side switch resistance between gnd and exposed pad, t j = 25 o c - 80 100 m w protections i lim p - channel power mosfet current - l imit peak current 4.0 5.5 7.0 a free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 5 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 ( c o n t . ) r e f e r t o t h e t y p i c a l a p p l i c a t i o n c i r c u i t s . t h e s e s p e c i f i c a t i o n s a p p l y o v e r v i n = 1 2 v , v o u t = 3 . 3 v a n d t a = - 4 0 ~ 8 5 o c , u n l e s s o t h e r w i s e s p e c i f i e d . v c c i s r e g u l a t e d b y a n i n t e r n a l r e g u l a t o r . t y p i c a l v a l u e s a r e a t t a = 2 5 o c . apw70 70/a symbol parameter test conditions min . typ . max . unit protections (cont.) v uv fb under - v oltage threshold v fb f alling 66 70 74 % fb under - v oltage hysteresis - 40 - mv fb under - v oltage debounce - 2 - m s v ov fb over - v oltage thresh old v fb rising 114 118 122 % fb over - v oltage hysteresis - 40 - mv t otp over - t empe r ature trip point - 150 - o c over - t empe r ature hysteresis - 5 0 - o c t d dead - time v lx = - 0.7v, v in = 4.75 ~ 20v - 30 - ns soft - start, enable , and input current s t ss soft - start interval 9 10.8 12 ms preceding delay before soft - s tart 9 10.8 12 ms en logic low voltage v en falling , v i n = 4 ~ 20v - - 0.5 v en logic high voltage v en rising, v i n = 4 ~ 20v 2.1 - - v en pin clamped voltage i en = 10ma 12 - 17 v p - channel power mosfet leakage current v en = 0v, v lx = 0v, v in = 20v - - 4 m a i fb fb pin input current v fb = 0.8v - 100 - +100 m a i en en pin input current v en < 3v - 500 - +500 m a free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 6 t y p i c a l o p e r a t i n g c h a r a c t e r i s t i c s reference voltage, v ref (v) j u n c t i o n t e m p e r a t u r e , t j ( o c ) r e f e r e n c e v o l t a g e v s . j u n c t i o n t e m p e r a t u r e oscillator frequency, f osc (khz) j u n c t i o n t e m p e r a t u r e , t j ( o c ) o s c i l l a t o r f r e q u e n c y v s . j u n c t i o n t e m p e r a t u r e output voltage, v out (v) s u p p l y v o l t a g e , v i n ( v ) o u t p u t v o l t a g e v s . s u p p l y v o l t a g e output voltage, v out (v) o u t p u t c u r r e n t , i o u t ( a ) o u t p u t v o l t a g e v s . o u t p u t c u r r e n t current-limit level, i lim (a) j u n c t i o n t e m p e r a t u r e , t j ( o c ) c u r r e n t - l i m i t l e v e l ( p e a k c u r r e n t ) v s . j u n c t i o n t e m p e r a t u r e vin input current, i vin (ma) v i n s u p p l y v o l t a g e , v i n ( v ) v i n i n p u t c u r r e n t v s . s u p p l y v o l t a g e 0.784 0.788 0.792 0.796 0.800 0.804 0.808 0.812 0.816 -50 -25 0 25 50 75 100 125 150 -50 -25 0 25 50 75 100 125 150 340 350 360 370 380 390 400 410 420 3.24 3.25 3.26 3.27 3.28 3.29 3.30 3.31 3.32 3.33 3.34 3.35 3.36 4 6 8 10 12 14 16 18 20 22 i out =0.2a i out =1a i out =2a i out =3a 3.24 3.25 3.26 3.27 3.28 3.29 3.30 3.31 3.32 3.33 3.34 3.35 3.36 0.0 0.5 1.0 1.5 2.0 2.5 3.0 v in =5v v in =12v 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 0 2 4 6 8 10 12 14 16 18 20 22 v fb =0.85v -50 -25 0 25 50 75 100 125 150 4.0 4.5 5.0 5.5 6.0 6.5 7.0 free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 7 t y p i c a l o p e r a t i n g c h a r a c t e r i s t i c s ( c o n t . ) efficiency o u t p u t c u r r e n t , i o u t ( a ) e f f i c i e n c y v s . o u t p u t c u r r e n t en clamp voltage, v en (v) e n i n p u t c u r r e n t , i e n ( m a ) e n c l a m p v o l t a g e v s . e n i n p u t c u r r e n t 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 0.001 0.01 0.1 1 10 APW7070A v out =3.3v v out =5v v in =12v, l10= m h(dcr=50 m w ) c1=10 m f, c4=22 m f 0 2 4 6 8 10 12 14 16 18 1 10 100 1000 10000 t j =-30 o c t j =25 o c t j =100 o c free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 8 o p e r a t i n g w a v e f o r m s ( r e f e r t o t h e a p p l i c a t i o n c i r c u i t 1 i n t h e s e c t i o n ? t y p i c a l a p p l i c a t i o n c i r c u i t s ? , v i n = 1 2 v , v o u t = 3 . 3 v , l 1 = 1 0 m h ) l o a d t r a n s i e n t r e s p o n s e l o a d t r a n s i e n t r e s p o n s e c h 1 : v o u t , 2 0 0 m v / d i v , d c , v o l t a g e o f f s e t = 3 . 3 v c h 2 : i l 1 , 1 a / d i v , d c t i m e : 5 0 m s / d i v c h 1 : v o u t , 1 0 0 m v / d i v , d c , v o l t a g e o f f s e t = 3 . 3 v c h 2 : i l 1 , 1 a / d i v , d c t i m e : 5 0 m s / d i v v out i l1 0 a 2 1 i out = 50ma - > 3a - > 50ma i out rise/fall time=10 m s 3 a v out i l1 0 a 0 a 2 2 1 1 i out = 50ma - > 3a - > 50ma i out rise/fall time=10 m s i out = 50ma - > 3a - > 50ma i out rise/fall time=10 m s 3 a 3 a a p w 7 0 7 0 a i l1 0.5 a 2 1 3 a v out i l1 i out = 0.5a - > 3a - > 0.5a i out rise/fall time=10 m s i l1 0.5 a 0.5 a 2 2 1 1 3 a 3 a v out i l1 i out = 0.5a - > 3a - > 0.5a i out rise/fall time=10 m s i out = 0.5a - > 3a - > 0.5a i out rise/fall time=10 m s p o w e r o n p o w e r o f f c h 1 : v i n , 5 v / d i v , d c c h 2 : v o u t , 2 v / d i v , d c c h 3 : i l 1 , 2 a / d i v , d c t i m e : 5 m s / d i v c h 1 : v i n , 5 v / d i v , d c c h 2 : v o u t , 2 v / d i v , d c c h 3 : i l 1 , 2 a / d i v , d c t i m e : 5 m s / d i v 2 1 v out v in i l1 3 i out = 3a 2 2 1 1 v out v in i l1 3 3 i out = 3a i out = 3a 2 1 v out v in i l1 3 i out = 3a 2 2 1 1 v out v in i l1 3 3 i out = 3a i out = 3a free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 9 o p e r a t i n g w a v e f o r m s ( c o n t . ) e n a b l e t h r o u g h e n p i n s h u t d o w n t h r o u g h e n p i n c h 1 : v e n , 5 v / d i v , d c c h 2 : v o u t , 2 v / d i v , d c c h 3 : i l 1 , 2 a / d i v , d c t i m e : 5 m s / d i v c h 1 : v e n , 5 v / d i v , d c c h 2 : v o u t , 2 v / d i v , d c c h 3 : i l 1 , 2 a / d i v , d c t i m e : 5 m s / d i v ( r e f e r t o t h e a p p l i c a t i o n c i r c u i t 1 i n t h e s e c t i o n ? t y p i c a l a p p l i c a t i o n c i r c u i t s ? , v i n = 1 2 v , v o u t = 3 . 3 v , l 1 = 1 0 m h ) 2 1 v out v en i l1 3 i out = 3a 2 2 1 1 v out v en i l1 3 3 i out = 3a i out = 3a 2 1 v out v en i l1 3 i out = 3a 2 2 1 1 v out v en i l1 3 3 i out = 3a i out = 3a o v e r c u r r e n t s h o r t c i r c u i t c h 1 : v o u t , 1 v / d i v , d c c h 2 : i l 1 , 2 a / d i v , d c t i m e : 5 0 m s / d i v c h 1 : v o u t , 1 v / d i v , d c c h 2 : i l 1 , 2 a / d i v , d c t i m e : 5 0 m s / d i v 2 1 v out i l1 i out = 0.5a - >6.4a 2 1 v out i l1 2 2 1 1 v out i l1 i out = 0.5a - >6.4a i out = 0.5a - >6.4a 2 1 v out i l1 v out is shorted to ground by a short wire 2 2 1 1 v out i l1 v out is shorted to ground by a short wire v out is shorted to ground by a short wire free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 1 0 o p e r a t i n g w a v e f o r m s ( c o n t . ) s w i t c h i n g w a v e f o r m s w i t c h i n g w a v e f o r m c h 1 : v l x , 5 v / d i v , d c c h 2 : i l 1 , 0 . 5 a / d i v , d c t i m e : 1 . 2 5 m s / d i v c h 1 : v l x , 5 v / d i v , d c c h 2 : i l 1 , 2 a / d i v , d c t i m e : 1 . 2 5 m s / d i v ( r e f e r t o t h e a p p l i c a t i o n c i r c u i t 1 i n t h e s e c t i o n ? t y p i c a l a p p l i c a t i o n c i r c u i t s ? , v i n = 1 2 v , v o u t = 3 . 3 v , l 1 = 1 0 m h ) 1 v lx i l1 2 i out = 0.2a 1 1 v lx i l1 2 2 i out = 0.2a i out = 0.2a 1 v lx i l1 2 i out = 3a 1 1 v lx i l1 2 2 i out = 3a i out = 3a l i n e t r a n s i e n t r e s p o n s e c h 1 : v o u t , 5 0 m v / d i v , d c , v o l t a g e o f f s e t = 3 . 3 v c h 2 : v i n , 5 v / d i v , d c , t i m e : 5 0 m s / d i v 2 1 v out v in 12 v 20 v v in = 12v -- > 20v -- > 12v v in rise/fall time=10 m s 2 2 1 1 v out v in 12 v 12 v 20 v 20 v v in = 12v -- > 20v -- > 12v v in rise/fall time=10 m s v in = 12v -- > 20v -- > 12v v in rise/fall time=10 m s free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 1 1 p i n d e s c r i p t i o n pin no. name function 1 vin power input. vin supplies the power (4.75v to 18 v) to the control circuitry, gate driver and step - down converter switch. connecting a ceramic bypass capacitor and a suitably large capacitor between vin and gnd eliminates swit ching noise and voltage ripple on the input to the ic. 2 en enable input. en is a digital input that turns the regulator on or off. drive en high to turn on the regulator, drive it low to turn it off. pull up with 100k w resistor for automatic startup. 3 ugnd gate driver power ground of the p - channel power mosfet. a linear regulator regulates a 5.5v voltage between vin and ugnd to supply power to p - channel mosfet gate driver. connect a ceramic capacitor (1 m f typ.) betwe en v in and u gnd for noise decoupling and stability of the linear regulator. 4 vcc bias input and 4.2v linear regulator?s output. this pin supplies the bias to some control circuits. the 4.2v linear regulator converts the voltage on vin to 4.2v to supply t he bias when no external 5v power supply is connected with vcc. connect a ceramic capacitor (1 m f typ.) between vcc and gnd for noise decoupling and stability of the linear regulator. 5 lx power switching output. connect this pin to the underside exposed p ad. 6 comp output of error amplifier. connect a series rc network from comp to gnd to compensate the regulation control loop. in some cases, an additional capacitor from comp to gnd is required for noise decoupling . 7 fb feedback input. the ic sense s fee dback voltage via fb and regulate the voltage at 0.8v. connecting fb with a resistor - divider from the output set the output voltage in the range from 0.8v to 90% v in . 8 gnd power and signal ground. 9 ( exposed pad ) lx power switching output. lx is the dr ain of the p - channel mosfet to supply power to the output. the exposed pad provide s current with lower impedance than pin 5 . connect the pad to output lc filter via a top - layer thermal pad on pcbs. the pcb will be a heat sink of the ic. b l o c k d i a g r a m lx v ref 0.8v soft-start and fault logic error amplifier fb inhibit 70%v ref uvp gnd por soft-start 4.2v regulator and power-on-reset v cc vcc v cc enable current sense amplifier en comp ovp 118%v ref oscillator 380khz slope compensation current comparator 0.8v ugnd vin over temperature protection zero-crossing comparator current limit v in fb 2.5v enok ug lg gate driver gate driver gm gate control linear regulator s free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 1 2 t y p i c a l a p p l i c a t i o n c i r c u i t 1 . 4 . 7 5 ~ 2 0 v s i n g l e p o w e r i n p u t s t e p - d o w n c o n v e r t e r ( w i t h c e r a m i c i n p u t / o u t p u t c a p a c i t o r s ) r e c o m m e n d e d f e e d b a c k c o m p e n s a t i o n n e t w o r k c o m p o n e n t s l i s t : v in (v) v out (v) l 1 ( m h) c 4 ( m f) c4 esr (m w ) r 1 (k w ) r2 (k w ) c7 (pf) r4 (k w ) c5 (pf) c6 (pf) 12 5 10 22 5 63 .4 12 68 24 820 22 12 5 10 44 3 63 .4 12 68 51 820 22 12 3.3 10 22 5 47 15 82 15 1000 22 12 3.3 10 44 3 47 15 82 33 1000 22 12 2 4.7 22 5 30 20 56 10 2200 22 12 2 4.7 44 3 30 20 56 20 2200 22 12 1.2 3.3 22 5 7.5 15 150 6.2 3300 22 12 1.2 3.3 44 3 7.5 15 150 12 3300 22 5 3.3 3.3 22 5 47 15 68 15 560 22 5 3.3 3.3 44 3 47 15 68 33 560 22 5 1.2 2.2 22 5 7.5 15 270 5.6 1500 22 5 1.2 2.2 44 3 7.5 15 270 12 1500 22 5 0.8 2.2 22 5 0 nc nc 2.7 2700 22 5 0.8 2.2 44 3 0 nc nc 6.2 2700 22 r2 1% lx en 2 vin 1 gnd 8 comp 6 9 u1 apw7070/a fb 7 ugnd 3 v out 0.8v~90%v in /3a l1 3a vcc 4 c3 1 m f c2 1 m f v in 4.75~20v c1 10 m f c5 r4 c6 c4 22 m f r1 1% r5 100k w v in c7 (optional) lx 5 free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 1 3 t y p i c a l a p p l i c a t i o n c i r c u i t ( c o n t . ) 2 . d u a l p o w e r i n p u t s s t e p - d o w n c o n v e r t e r ( v i n = 4 . 7 5 ~ 2 0 v ) 3 . 4 . 7 5 ~ 5 . 5 v s i n g l e p o w e r i n p u t s t e p - d o w n c o n v e r t e r + 5v r2 1% lx en 2 vin 1 gnd 8 comp 6 9 u1 apw7070/a fb 7 ugnd 3 v out 0.8v~90%v in /3a l1 3a vcc 4 c3 1 m f c2 1 m f v in 4.75~20v c1 10 m f c5 r4 c6 d1 schottky diode c4 22 m f r1 1% r5 100k w v in c7 (optional) lx 5 r2 1% lx en 2 vin 1 gnd 8 comp 6 9 u1 apw7070/a fb 7 ugnd 3 v out 0.8v~90%v in /3a l1 3a vcc 4 c3 1 m f c2 1 m f v in 4.75~5.5v c1 10 m f c5 r4 c6 c4 22 m f r1 1% c7 (optional) r5 100k w v in lx 5 free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 1 4 t y p i c a l a p p l i c a t i o n c i r c u i t ( c o n t . ) 4 . + 1 2 v s i n g l e p o w e r i n p u t s t e p - d o w n c o n v e r t e r ( w i t h e l e c t r o l y t i c i n p u t / o u t p u t c a p a c i t o r s ) r2 15k 1% lx en 2 vin 1 gnd 8 comp 6 9 u1 apw7070/a fb 7 ugnd 3 v out +3.3v/3a l1 10 m h 3a vcc 4 c3 1 m f c2 1 m f v in +12v c1 2.2 m f c5 4700pf r4 56k c6 22pf c4 470 m f r1 47k w 1% r5 100k w v in c8 470 m f c7 33pf lx 5 (esr=30m w) free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 1 5 f u n c t i o n d e s c r i p t i o n m a i n c o n t r o l l o o p t h e a p w 7 0 7 0 / a i s a c o n s t a n t f r e q u e n c y c u r r e n t m o d e s w i t c h i n g r e g u l a t o r . d u r i n g n o r m a l o p e r a t i o n , t h e i n t e r - n a l p - c h a n n e l p o w e r m o s f e t i s t u r n e d o n e a c h c y c l e w h e n t h e o s c i l l a t o r s e t s a n i n t e r n a l r s l a t c h a n d w o u l d b e t u r n e d o f f w h e n a n i n t e r n a l c u r r e n t c o m p a r a t o r ( i c m p ) r e s e t s t h e l a t c h . t h e p e a k i n d u c t o r c u r r e n t a t w h i c h i c m p r e s e t s t h e r s l a t c h i s c o n t r o l l e d b y t h e v o l t a g e o n t h e c o m p p i n , w h i c h i s t h e o u t p u t o f t h e e r r o r a m p l i f i e r ( e a m p ) . a n e x t e r n a l r e s i s t i v e d i v i d e r c o n n e c t e d b e t w e e n v o u t a n d g r o u n d a l l o w s t h e e a m p t o r e c e i v e a n o u t p u t f e e d b a c k v o l t a g e v f b a t f b p i n . w h e n t h e l o a d c u r r e n t i n c r e a s e s , i t c a u s e s a s l i g h t d e c r e a s e i n v f b r e l a t i v e t o t h e 0 . 8 v r e f e r e n c e , w h i c h i n t u r n c a u s e s t h e c o m p v o l t - a g e t o i n c r e a s e u n t i l t h e a v e r a g e i n d u c t o r c u r r e n t m a t c h e s t h e n e w l o a d c u r r e n t . v c c p o w e r - o n - r e s e t ( p o r ) a n d e n u n d e r v o l t a g e l o c k o u t t h e a p w 7 0 7 0 / a k e e p s m o n i t o r i n g t h e v o l t a g e o n v c c p i n t o p r e v e n t w r o n g l o g i c o p e r a t i o n s w h i c h m a y o c c u r w h e n v c c v o l t a g e i s n o t h i g h e n o u g h f o r t h e i n t e r n a l c o n t r o l c i r c u i t r y t o o p e r a t e . t h e v c c p o r h a s a r i s i n g t h r e s h o l d o f 3 . 9 v ( t y p i c a l ) w i t h 0 . 1 5 v o f h y s t e r e s i s . a n e x t e r n a l u n d e r v o l t a g e l o c k o u t ( u v l o ) i s s e n s e d a n d p r o g r a m m e d a t t h e e n p i n . t h e e n u v l o h a s a r i s i n g t h r e s h o l d o f 2 . 5 v w i t h 0 . 2 v o f h y s t e r e s i s . t h e e n u v l o s h o u l d b e p r o g r a m m e d b y c o n n e c t i n g a r e s i s t i v e d i v i d e r f r o m v i n t o e n t o g n d . a f t e r t h e v c c , e n , a n d v i n - t o - u g n d v o l t a g e s e x c e e d t h e i r r e s p e c t i v e v o l t a g e t h r e s h o l d s , t h e i c s t a r t s a s t a r t - u p p r o - c e s s a n d t h e n r a m p s u p t h e o u t p u t v o l t a g e t o t h e s e t t i n g o f o u t p u t v o l t a g e . c o n n e c t i n g a r c n e t w o r k f r o m e n t o g n d i s f o r s e t t i n g a t u r n - o n d e l a y t h a t c a n b e u s e d t o s e q u e n c e t h e o u t p u t v o l t a g e s o f m u l t i p l e d e v i c e s . v c c 4 . 2 v l i n e a r r e g u l a t o r v c c i s t h e o u t p u t t e r m i n a l o f t h e i n t e r n a l 4 . 2 v l i n e a r r e g u - l a t o r w h i c h i s p o w e r e d f r o m v i n a n d p r o v i d e s p o w e r t o t h e a p w 7 0 7 0 / a . t h e l i n e a r r e g u l a t o r d e s i g n e d t o b e s t a b l e w i t h a l o w - e s r c e r a m i c o u t p u t c a p a c i t o r p o w e r s t h e i n - t e r n a l c o n t r o l c i r c u i t r y , t h e n b y p a s s e s v c c t o g n d w i t h a c e r a m i c c a p a c i t o r o f a t l e a s t 0 . 2 2 m f . i n o r d e r t o p r o v i d e g o o d n o i s e d e c o u p l i n g , p l e a s e p l a c e t h e c a p a c i t o r p h y s i - c a l l y c l o s e t o t h e i c . t h e l i n e a r r e g u l a t o r i s n o t i n t e n d e d f o r p o w e r i n g u p a n y e x t e r n a l l o a d s . d o n o t c o n n e c t a n y e x t e r n a l l o a d s t o v c c . t h e l i n e a r r e g u l a t o r i s a l s o e q u i p p e d w i t h c u r r e n t - l i m i t p r o t e c t i o n t o p r o t e c t i t s e l f d u r i n g o v e r - l o a d o r s h o r t - c i r c u i t c o n d i t i o n s o n v c c p i n . v i n - t o - u g n d 5 . 5 v l i n e a r r e g u l a t o r t h e b u i l t - i n 5 . 5 v l i n e a r r e g u l a t o r r e g u l a t e s a 5 . 5 v v o l t a g e b e t w e e n v i n a n d u g n d p i n s t o s u p p l y b i a s a n d g a t e c h a r g e f o r t h e p - c h a n n e l p o w e r m o s f e t g a t e d r i v e r . t h e l i n e a r r e g u l a t o r i s d e s i g n e d t o b e s t a b l e w i t h a l o w - e s r c e r a m i c o u t p u t c a p a c i t o r o f a t l e a s t 0 . 2 2 m f . i t i s a l s o e q u i p p e d w i t h c u r r e n t - l i m i t f u n c t i o n t o p r o t e c t i t s e l f d u r - i n g o v e r - l o a d o r s h o r t - c i r c u i t c o n d i t i o n s b e t w e e n v i n a n d u g n d . t h e a p w 7 0 7 0 / a s h u t s o f f t h e o u t p u t o f t h e c o n v e r t e r s w h e n t h e o u t p u t v o l t a g e o f t h e l i n e a r r e g u l a t o r i s b e l o w 3 . 5 v ( t y p i c a l ) . t h e i c r e s u m e s w o r k i n g b y i n i t i a t i n g a n e w s o f t - s t a r t p r o c e s s w h e n t h e l i n e a r r e g u l a t o r ? s o u t p u t v o l t a g e i s a b o v e t h e u n d e r v o l t a g e l o c k o u t v o l t a g e t h r e s h o l d . d i g i t a l s o f t - s t a r t t h e a p w 7 0 7 0 / a h a s a b u i l t - i n d i g i t a l s o f t - s t a r t t o c o n t r o l t h e o u t p u t v o l t a g e r i s e a n d l i m i t t h e i n p u t c u r r e n t s u r g e d u r i n g s t a r t - u p . d u r i n g s o f t - s t a r t , a n i n t e r n a l r a m p , c o n - n e c t e d t o t h e o n e o f t h e p o s i t i v e i n p u t s o f t h e e r r o r a m p l i f i e r , r i s e s u p f r o m 0 v t o 1 v t o r e p l a c e t h e r e f e r e n c e v o l t a g e ( 0 . 8 v ) u n t i l t h e r a m p v o l t a g e r e a c h e s t h e r e f e r - e n c e v o l t a g e . t h e d e v i c e i s d e s i g n e d w i t h a p r e c e d i n g d e l a y a b o u t 1 0 . 8 m s ( t y p i c a l ) b e f o r e s o f t - s t a r t p r o c e s s . e n a b l e / s h u t d o w n d r i v i n g e n t o g r o u n d p l a c e s t h e a p w 7 0 7 0 / a i n s h u t d o w n . w h e n i n s h u t d o w n , t h e i n t e r n a l p o w e r m o s f e t t u r n s o f f , a l l i n t e r n a l c i r c u i t r y s h u t s d o w n a n d t h e q u i e s c e n t s u p p l y c u r r e n t o f v i n r e d u c e s t o < 1 m a ( t y p i c a l ) . o u t p u t u n d e r - v o l t a g e p r o t e c t i o n i n t h e p r o c e s s o f o p e r a t i o n , i f a s h o r t - c i r c u i t o c c u r s , t h e o u t p u t v o l t a g e w i l l d r o p q u i c k l y . b e f o r e t h e c u r r e n t - l i m i t c i r c u i t r e s p o n d s , t h e o u t p u t v o l t a g e w i l l f a l l o u t o f t h e r e - free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 1 6 f u n c t i o n d e s c r i p t i o n ( c o n t . ) o u t p u t u n d e r - v o l t a g e p r o t e c t i o n ( c o n t . ) q u i r e d r e g u l a t i o n r a n g e . t h e u n d e r v o l t a g e c o n t i n u a l l y m o n i t o r s t h e f b v o l t a g e a f t e r s o f t - s t a r t i s c o m p l e t e d . i f a l o a d s t e p i s s t r o n g e n o u g h t o p u l l t h e o u t p u t v o l t a g e l o w e r t h a n t h e u n d e r v o l t a g e t h r e s h o l d , t h e i c s h u t s d o w n c o n v e r t e r ? s o u t p u t . t h e u n d e r v o l t a g e t h r e s h o l d i s 7 0 % o f t h e n o m i n a l o u t p u t v o l t a g e . t h e u n d e r v o l t a g e c o m p a r a - t o r h a s a b u i l t - i n 2 m s n o i s e f i l t e r t o p r e v e n t t h e c h i p s f r o m w r o n g u v p s h u t d o w n c a u s e d b y n o i s e . t h e u n d e r - v o l t - a g e p r o t e c t i o n w o r k s i n a h i c c u p m o d e w i t h o u t l a t c h e d s h u t d o w n . t h e i c w i l l i n i t i a t e a n e w s o f t - s t a r t p r o c e s s a t t h e e n d o f t h e p r o c e e d i n g d e l a y . o v e r - t e m p e r a t u r e p r o t e c t i o n ( o t p ) t h e o v e r - t e m p e r a t u r e c i r c u i t l i m i t s t h e j u n c t i o n t e m p e r a - t u r e o f t h e a p w 7 0 7 0 / a . w h e n t h e j u n c t i o n t e m p e r a t u r e e x c e e d s t j = + 1 5 0 o c , a t h e r m a l s e n s o r t u r n s o f f t h e p o w e r m o s f e t , a l l o w i n g t h e d e v i c e s t o c o o l . t h e t h e r m a l s e n - s o r a l l o w s t h e c o n v e r t e r t o s t a r t a s t a r t - u p p r o c e s s a n d r e g u l a t e t h e o u t p u t v o l t a g e a g a i n a f t e r t h e j u n c t i o n t e m - p e r a t u r e c o o l s b y 5 0 o c . t h e o t p i s d e s i g n e d w i t h a 5 0 o c h y s t e r e s i s t o l o w e r t h e a v e r a g e t j d u r i n g c o n t i n u o u s t h e r - m a l o v e r l o a d c o n d i t i o n s , i n c r e a s i n g l i f e t i m e o f t h e i c . o v e r - v o l t a g e p r o t e c t i o n t h e o v e r v o l t a g e f u n c t i o n m o n i t o r s t h e o u t p u t v o l t a g e b y f b p i n . t h e f b v o l t a g e s h o u l d i n c r e a s e o v e r 1 1 8 % o f t h e r e f e r e n c e v o l t a g e d u e t o t h e h i g h - s i d e m o s f e t f a i l u r e , o r f o r o t h e r r e a s o n s , t h e o v e r v o l t a g e p r o t e c t i o n c o m p a r a t o r , w i l l f o r c e t h e l o w - s i d e m o s f e t g a t e d r i v e r h i g h . a s s o o n a s t h e o u t p u t v o l t a g e i s w i t h i n r e g u l a t i o n , t h e o v p c o m p a r a t o r i s d i s e n g a g e d . t h e c h i p s w i l l r e - s t o r e i t s n o r m a l o p e r a t i o n . t h i s o v p s c h e m e o n l y c l a m p s t h e v o l t a g e o v e r s h o o t , a n d d o e s n o t i n v e r t t h e o u t p u t v o l t - a g e w h e n o t h e r w i s e a c t i v a t e d w i t h a c o n t i n u o u s l y h i g h o u t p u t f r o m l o w - s i d e m o s f e t d r i v e r - a c o m m o n p r o b - l e m f o r o v p s c h e m e s w i t h a l a t c h . c u r r e n t - l i m i t p r o t e c t i o n t h e a p w 7 0 7 0 / a m o n i t o r s t h e o u t p u t c u r r e n t , f l o w i n g t h r o u g h t h e p - c h a n n e l p o w e r m o s f e t , a n d l i m i t s t h e c u r r e n t p e a k a t c u r r e n t - l i m i t l e v e l t o p r e v e n t l o a d s a n d t h e i c f r o m d a m a g e s d u r i n g o v e r l o a d o r s h o r t - c i r c u i t c o n d i t i o n s . f r e q u e n c y f o l d b a c k w h e n t h e o u t p u t i s s h o r t e n e d t o g r o u n d , t h e f r e q u e n c y o f t h e o s c i l l a t o r w i l l b e r e d u c e d t o a b o u t 8 0 k h z . t h i s l o w e r f r e q u e n c y a l l o w s t h e i n d u c t o r c u r r e n t t o s a f e l y d i s c h a r g e , t h e r e b y p r e v e n t i n g c u r r e n t r u n a w a y . t h e o s c i l l a t o r ? s f r e - q u e n c y w i l l g r a d u a l l y i n c r e a s e t o i t s d e s i g n e d r a t e w h e n t h e f e e d b a c k v o l t a g e o n f b a g a i n a p p r o a c h e s 0 . 8 v . free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 1 7 a p p l i c a t i o n i n f o r m a t i o n (v) ) r2 r1 (1 0.8 v out + = p o w e r s e q u e n c i n g t h e a p w 7 0 7 0 / a c a n o p e r a t e w i t h s i n g l e o r d u a l p o w e r i n p u t ( s ) . i n d u a l - p o w e r a p p l i c a t i o n s , t h e v o l t a g e ( v c c ) a p - p l i e d a t v c c p i n m u s t b e l o w e r t h a n t h e v o l t a g e ( v i n ) o n v i n p i n . t h e i n t e r n a l p a r a s i t i c d i o d e f r o m v c c t o v i n w i l l c o n d u c t d u e t o t h e f o r w a r d - v o l t a g e b e t w e e n v c c a n d v i n . t h e r e f o r e , v i n m u s t b e p r o v i d e d b e f o r e v c c . s e t t i n g o u t p u t v o l t a g e t h e r e g u l a t e d o u t p u t v o l t a g e i s d e t e r m i n e d b y : s u g g e s t e d r 2 i s i n t h e r a n g e f r o m 1 k t o 2 0 k w . f o r p o r t a b l e a p p l i c a t i o n s , a 1 0 k r e s i s t o r i s s u g g e s t e d f o r r 2 . t o p r e v e n t s t r a y p i c k u p , p l e a s e l o c a t e r e s i s t o r s r 1 a n d r 2 c l o s e t o a p w 7 0 7 0 / a . i n p u t c a p a c i t o r s e l e c t i o n u s e s m a l l c e r a m i c c a p a c i t o r s f o r h i g h f r e q u e n c y d e c o u p l i n g a n d b u l k c a p a c i t o r s t o s u p p l y t h e s u r g e c u r r e n t n e e d e d e a c h t i m e t h e p - c h a n n e l p o w e r m o s f e t ( q 1 ) t u r n s o n . p l a c e t h e s m a l l c e r a m i c c a p a c i t o r s p h y s i c a l l y c l o s e t o t h e v i n a n d b e t w e e n t h e v i n a n d g n d . t h e i m p o r t a n t p a r a m e t e r s f o r t h e b u l k i n p u t c a p a c i t o r a r e t h e v o l t a g e r a t i n g a n d t h e r m s c u r r e n t r a t i n g . f o r r e l i a b l e o p e r a t i o n , s e l e c t t h e b u l k c a p a c i t o r w i t h v o l t a g e a n d c u r r e n t r a t i n g s a b o v e t h e m a x i m u m i n p u t v o l t a g e a n d l a r g e s t r m s c u r r e n t r e q u i r e d b y t h e c i r c u i t . t h e c a p a c i t o r v o l t a g e r a t i n g s h o u l d b e a t l e a s t 1 . 2 5 t i m e s g r e a t e r t h a n t h e m a x i m u m i n p u t v o l t a g e a n d a v o l t a g e r a t i n g o f 1 . 5 t i m e s i s a c o n s e r v a t i v e g u i d e l i n e . t h e r m s c u r r e n t ( i r m s ) o f t h e b u l k i n p u t c a p a c i t o r i s c a l c u l a t e d a s t h e f o l l o w i n g e q u a t i o n : (a) d) - (1 d i i out rms = w h e r e d i s t h e d u t y c y c l e o f t h e p o w e r m o s f e t . f o r a t h r o u g h h o l e d e s i g n , s e v e r a l e l e c t r o l y t i c c a p a c i t o r s m a y b e n e e d e d . f o r s u r f a c e m o u n t d e s i g n s , s o l i d t a n t a l u m c a p a c i t o r s c a n b e u s e d , b u t c a u t i o n m u s t b e e x e r c i s e d w i t h r e g a r d t o t h e c a p a c i t o r s u r g e c u r r e n t r a t i n g . f i g u r e 1 . c o n v e r t e r w a v e f o r m s o u t p u t c a p a c i t o r s e l e c t i o n a n o u t p u t c a p a c i t o r i s r e q u i r e d t o f i l t e r t h e o u t p u t a n d s u p p l y t h e l o a d t r a n s i e n t c u r r e n t . t h e f i l t e r i n g r e q u i r e m e n t s a r e a f u n c t i o n o f t h e s w i t c h i n g f r e q u e n c y a n d t h e r i p p l e c u r r e n t ( d i ) . t h e o u t p u t r i p p l e i s t h e s u m o f t h e v o l t a g e s , h a v i n g p h a s e s h i f t , a c r o s s t h e e s r a n d t h e i d e a l o u t p u t c a p a c i t o r . t h e p e a k - t o - p e a k v o l t a g e o f t h e e s r i s c a l c u l a t e d a s t h e f o l l o w i n g e q u a t i o n s : . . . . . . . . . . . ( 1 ) . . . . . . . . . . . ( 2 ) l f d) - (1 v i osc out = d t h e p e a k - t o - p e a k v o l t a g e o f t h e i d e a l o u t p u t c a p a c i t o r i s c a l c u l a t e d a s t h e f o l l o w i n g e q u a t i o n s : v in v out c in c out l q1 lx esr i l i out i q1 i cout vin q2 i out v lx t=1/f osc i l i q1 i cout i out i i dt v out v out v v d in out = . . . . . . . . . . . ( 3 ) esr . i v esr d = free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 1 8 a p p l i c a t i o n i n f o r m a t i o n ( c o n t . ) o u t p u t c a p a c i t o r s e l e c t i o n ( c o n t . ) (v) c f 8 i v out osc cout d = d . . . . . . . . . . . ( 4 ) f o r t h e a p p l i c a t i o n s u s i n g b u l k c a p a c i t o r s , t h e d v c o u t i s m u c h s m a l l e r t h a n t h e v e s r a n d c a n b e i g n o r e d . t h e r e f o r e , t h e a c p e a k - t o - p e a k o u t p u t v o l t a g e ( d v o u t ) i s s h o w n b e l o w : (v) esr i v out d = d . . . . . . . . . . . ( 5 ) w h e r e f o r t h e a p p l i c a t i o n s u s i n g c e r a m i c c a p a c i t o r s , t h e v e s r i s m u c h s m a l l e r t h a n t h e d v c o u t a n d c a n b e i g n o r e d . t h e r e f o r e , t h e a c p e a k - t o - p e a k o u t p u t v o l t a g e ( d v o u t ) i s c l o s e t o d v c o u t . t h e l o a d t r a n s i e n t r e q u i r e m e n t i s a f u n c t i o n o f t h e s l e w r a t e ( d i / d t ) a n d t h e m a g n i t u d e o f t h e t r a n s i e n t l o a d c u r r e n t . t h e s e r e q u i r e m e n t s a r e g e n e r a l l y m e t w i t h a m i x o f c a - p a c i t o r s a n d c a r e f u l l a y o u t . h i g h f r e q u e n c y c a p a c i t o r s i n i t i a l l y s u p p l y t h e t r a n s i e n t a n d s l o w t h e c u r r e n t l o a d r a t e s e e n b y t h e b u l k c a p a c i t o r s . t h e b u l k f i l t e r c a p a c i t o r v a l u e s a r e g e n e r a l l y d e t e r m i n e d b y t h e e s r ( e f f e c t i v e s e r i e s r e s i s t a n c e ) a n d v o l t a g e r a t i n g r e q u i r e m e n t s r a t h e r t h a n a c t u a l c a p a c i t a n c e r e q u i r e m e n t s . h i g h f r e q u e n c y d e c o u p l i n g c a p a c i t o r s s h o u l d b e p l a c e d a s c l o s e t o t h e p o w e r p i n s o f t h e l o a d a s p h y s i c a l l y p o s s i b l e . b e c a r e f u l n o t t o a d d i n d u c t a n c e i n t h e c i r c u i t b o a r d w i r i n g t h a t c o u l d c a n c e l t h e u s e f u l n e s s o f t h e s e l o w i n d u c t a n c e c o m p o n e n t s . a n 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 e s r v a l u e i s r e l a t e d t o t h e c a s e s i z e w i t h l o w e r e s r a v a i l a b l e i n l a r g e r c a s e s i z e s . h o w e v e r , t h e e q u i v a l e n t s e r i e s i n d u c t a n c e ( e s l ) o f t h e s e c a p a c i t o r s i n c r e a s e s w i t h c a s e s i z e a n d c a n r e d u c e t h e u s e f u l n e s s o f t h e c a p a c i t o r t o h i g h s l e w - r a t e t r a n s i e n t l o a d i n g . i n d u c t o r v a l u e c a l c u l a t i o n . . . . . . . . . . . ( 6 ) in(max) in v v = t h e o p e r a t i n g f r e q u e n c y a n d i n d u c t o r s e l e c t i o n a r e i n t e r r e l a t e d i n t h a t h i g h e r o p e r a t i n g f r e q u e n c i e s p e r m i t t h e u s e o f a s m a l l e r i n d u c t o r f o r t h e s a m e a m o u n t o f i n d u c t o r r i p p l e c u r r e n t . h o w e v e r , t h i s i s a t t h e e x p e n s e o f e f f i c i e n c y d u e t o a n i n c r e a s e i n m o s f e t g a t e c h a r g e l o s s e s . t h e e q u a t i o n ( 2 ) s h o w s t h a t t h e i n d u c t a n c e v a l u e h a s a d i r e c t e f f e c t o n r i p p l e c u r r e n t . a c c e p t i n g l a r g e r v a l u e s o f r i p p l e c u r r e n t a l l o w s t h e u s e o f l o w i n d u c t a n c e s , b u t r e s u l t s i n h i g h e r o u t p u t v o l t a g e r i p p l e a n d g r e a t e r c o r e l o s s e s . a r e a s o n a b l e s t a r t i n g p o i n t f o r s e t t i n g r i p p l e c u r r e n t i s d i 0 . 4 i o u t ( m a x ) . r e m e m b e r , t h e m a x i m u m r i p p l e c u r r e n t o c c u r s a t t h e m a x i m u m i n p u t v o l t a g e . t h e m i n i m u m i n d u c t a n c e o f t h e i n d u c t o r i s c a l c u l a t e d b y u s i n g t h e f o l l o w i n g e q u a t i o n : layout consideration i n h i g h p o w e r s w i t c h i n g r e g u l a t o r , a c o r r e c t l a y o u t i s i m p o r t a n t t o e n s u r e p r o p e r o p e r a t i o n o f t h e r e g u l a t o r . i n g e n e r a l , i n t e r c o n n e c t i n g i m p e d a n c e s h o u l d b e m i n i m i z e d b y u s i n g s h o r t , w i d e p r i n t e d c i r c u i t t r a c e s . s i g n a l a n d p o w e r g r o u n d s a r e t o b e k e p t s e p a r a t i n g a n d f i - n a l l y c o m b i n e d u s i n g g r o u n d p l a n e c o n s t r u c t i o n o r s i n g l e p o i n t g r o u n d i n g . f i g u r e 2 i l l u s t r a t e s t h e l a y o u t , w i t h b o l d l i n e s i n d i c a t i n g h i g h c u r r e n t p a t h s . c o m p o n e n t s a l o n g t h e b o l d l i n e s s h o u l d b e p l a c e d c l o s e t o g e t h e r . b e l o w i s a c h e c k l i s t f o r y o u r l a y o u t : 1 . f i r s t l y , t o i n i t i a l t h e l a y o u t b y p l a c i n g t h e p o w e r c o m p o n e n t s . o r i e n t t h e p o w e r c i r c u i t r y t o a c h i e v e a c l e a n p o w e r f l o w p a t h . i f p o s s i b l e , m a k e a l l t h e c o n - n e c t i o n s o n o n e s i d e o f t h e p c b w i t h w i d e , c o p p e r f i l l e d a r e a s . f i g u r e 2 . c u r r e n t p a t h d i a g r a m lx en 2 vin 1 gnd 8 comp 6 9 u1 apw7070/a fb 7 l1 vcc 4 c3 + v in - c1 c5 r4 c6 c4 load compensation network ugnd 3 c2 lx 5 + v out - c8 r2 r1 c7 (optional) feedback divider 1.2 v l 380000 ) v - (v v in out in out (h) v 456000 ) v - (v v l in out in out 3 free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 1 9 layout consideration (cont.) 5 . p l a c e t h e d e c o u p l i n g c e r a m i c c a p a c i t o r c 1 n e a r t h e v i n a s c l o s e a s p o s s i b l e . t h e b u l k c a p a c i t o r s c 8 a r e a l s o p l a c e d n e a r v i n . u s e a w i d e p o w e r g r o u n d p l a n e t o c o n n e c t t h e c 1 , c 8 , a n d c 4 t o p r o v i d e a l o w i m - p e d a n c e p a t h b e t w e e n t h e c o m p o n e n t s f o r l a r g e a n d h i g h s l e w r a t e c u r r e n t . f i g u r e 3 . r e c o m m e n d e d l a y o u t d i a g r a m exposed pad die top v lx plane pcb ambient air 118 mil 102 mil sop-8p 5 6 7 8 1 2 3 4 f i g u r e 4 . 2 . i n f i g u r e 2 , t h e l o o p s w i t h s a m e c o l o r b o l d l i n e s c o n d u c t h i g h s l e w r a t e c u r r e n t . t h e s e i n t e r c o n n e c t i n g i m p e d a n c e s s h o u l d b e m i n i m i z e d b y u s i n g w i d e , s h o r t p r i n t e d c i r c u i t t r a c e s . 3 . k e e p t h e s e n s i t i v e s m a l l s i g n a l n o d e s ( f b , c o m p ) a w a y f r o m s w i t c h i n g n o d e s ( l x o r o t h e r s ) o n t h e p c b . t h e r e f o r e , p l a c e t h e f e e d b a c k d i v i d e r a n d t h e f e e d - b a c k c o m p e n s a t i o n n e t w o r k c l o s e t o t h e i c t o a v o i d s w i t c h i n g n o i s e . c o n n e c t t h e g r o u n d o f f e e d b a c k d i v i d e r d i r e c t l y t o t h e g n d p i n o f t h e i c u s i n g a d e d i c a t e d g r o u n d t r a c e . 4 . t h e v c c d e c o u p l i n g c a p a c i t o r s h o u l d b e r i g h t n e x t t o t h e v c c a n d g n d p i n s . c a p a c i t o r c 2 s h o u l d b e c o n n e c t e d a s c l o s e t o t h e v i n a n d u g n d p i n s a s p o s s i b l e . sop-8p 5 6 7 8 1 2 3 4 c 1 l1 c 4 load v in gnd v out gnd v lx a p p l i c a t i o n i n f o r m a t i o n ( c o n t . ) t h e r m a l c o n s i d e r a t i o n i n f i g u r e 4 , t h e s o p - 8 p i s a c o s t - e f f e c t i v e p a c k a g e f e a - t u r i n g a s m a l l s i z e , l i k e a s t a n d a r d s o p - 8 , a n d a b o t t o m e x p o s e d p a d t o m i n i m i z e t h e t h e r m a l r e s i s t a n c e o f t h e p a c k a g e , b e i n g a p p l i c a b l e t o h i g h c u r r e n t a p p l i c a t i o n s . t h e e x p o s e d p a d m u s t b e s o l d e r e d t o t h e t o p v l x p l a n e . t h e c o p p e r o f t h e v l x p l a n e o n t h e t o p l a y e r c o n d u c t s h e a t i n t o t h e p c b a n d a i r . p l e a s e e n l a r g e t h e a r e a o f v l x p l a n t o r e d u c e s t h e c a s e - t o - a m b i e n t r e s i s t a n c e ( q c a ). free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 2 0 p a c k a g e i n f o r m a t i o n s o p - 8 p thermal pad d d1 e 2 e 1 e e b a 2 a a 1 view a l 0 . 2 5 gauge plane seating plane q note : 1. followed from jedec ms-012 ba. 2. dimension "d" does not include mold flash, protrusions or gate burrs. mold flash, protrusion or gate burrs shall not exceed 6 mil per side . 3. dimension "e" does not include inter-lead flash or protrusions. inter-lead flash and protrusions shall not exceed 10 mil per side. 0.020 0.010 0.020 0.050 0.006 0.063 max. 0.40 l q 0 o c e e h e1 0.25 d c b 0.17 0.31 0.016 1.27 8 o c 0 o c 8 o c 0.50 1.27 bsc 0.51 0.25 0.050 bsc 0.010 0.012 0.007 millimeters min. s y m b o l a1 a2 a 0.00 1.25 sop-8p max. 0.15 1.60 min. 0.000 0.049 inches d1 2.50 0.098 2.00 0.079 e2 3.50 3.00 0.138 0.118 4.80 5.00 0.189 0.197 3.80 4.00 0.150 0.157 5.80 6.20 0.228 0.244 h x 4 5 o c see view a -t- seating plane < 4 mils free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 2 1 c a r r i e r t a p e & r e e l d i m e n s i o n s application a h t1 c d d w e1 f 330.0 ? 2.00 50 min. 12.4+2.00 - 0.00 13.0+0.50 - 0.20 1.5 min. 20.2 min. 12.0 ? 0.30 1.75 ? 0.10 5.5 ? 0.05 p 0 p1 p 2 d 0 d1 t a 0 b 0 k 0 sop - 8p 4.0 ? 0.10 8.0 ? 0.10 2.0 ? 0.05 1.5+0.10 - 0.00 1.5 min. 0.6+0.00 - 0. 40 6.40 ? 0.20 5.20 ? 0.20 2.10 ? 0.20 (mm) package type unit quantity sop - 8p tape & reel 2500 d e v i c e s p e r u n i t a e 1 a b w f t p0 od0 b a0 p2 k0 b 0 section b-b section a-a od1 p1 h t1 a d free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 2 2 t a p i n g d i r e c t i o n i n f o r m a t i o n sop-8p user direction of feed c l a s s i f i c a t i o n p r o f i l e free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 2 3 c l a s s i f i c a t i o n r e f l o w p r o f i l e s profile feature sn - pb eutectic assembly pb - free assembly preheat & soak temperature min (t smin ) temperature max (t smax ) time (t smin to t smax ) ( t s ) 100 c 150 c 60 - 120 seconds 150 c 200 c 60 - 1 2 0 seconds average ramp - up rate (t smax to t p ) 3 c/second ma x. 3 c/second max. liquidous temperature ( t l ) time at l iquidous (t l ) 183 c 60 - 150 seconds 217 c 60 - 150 seconds peak package body temperature (t p ) * see classification temp in table 1 see classification temp in table 2 time (t p ) ** within 5 c of the spe cified c lassification t emperature ( t c ) 2 0 ** seconds 3 0 ** seconds average r amp - down rate (t p to t smax ) 6 c/second max. 6 c/second max. time 25 c to p eak t emperature 6 minutes max. 8 minutes max. * tolerance for peak profile temperature (t p ) is defined as a supplier minimum and a user maximum. ** tolerance for time at peak profile temperature (t p ) is defined as a supplier minimum and a user maximum. table 2. pb - free process ? classification temperatures (tc) package thickness volume mm 3 <350 volume mm 3 350 - 2000 volume mm 3 >2000 <1.6 mm 260 c 260 c 260 c 1.6 mm ? 2.5 mm 260 c 250 c 245 c 3 2.5 mm 250 c 245 c 245 c table 1. snpb eutectic process ? classification temperatures (tc) package thickness volume mm 3 <350 volume mm 3 3 350 <2.5 mm 235 c 22 0 c 3 2.5 mm 220 c 220 c test item method description solderability jesd - 22, b102 5 sec, 245 c holt jesd - 22, a108 1000 hrs, bias @ t j =125 c pct jesd - 22, a102 168 hrs, 100 % rh, 2atm , 121 c tct jesd - 22, a104 500 cycles, - 65 c~150 c hbm mil - std - 883 - 3015.7 vhbm ? 2kv mm jesd - 22, a1 15 vmm ? 200v latch - up jesd 78 10ms, 1 tr ? 100ma r e l i a b i l i t y t e s t p r o g r a m free datasheet http://www.datasheetlist.com/ c o p y r i g h t ? a n p e c e l e c t r o n i c s c o r p . r e v . a . 4 - n o v . , 2 0 1 0 a p w 7 0 7 0 / a w w w . a n p e c . c o m . t w 2 4 c u s t o m e r s e r v i c e a n p e c e l e c t r o n i c s c o r p . head office : no.6, dusing 1st road, sbip, hsin-chu, taiwan, r.o.c. tel : 886-3-5642000 fax : 886-3-5642050 t a i p e i b r a n c h : 2 f , n o . 1 1 , l a n e 2 1 8 , s e c 2 j h o n g s i n g r d . , s i n d i a n c i t y , t a i p e i c o u n t y 2 3 1 4 6 , t a i w a n t e l : 8 8 6 - 2 - 2 9 1 0 - 3 8 3 8 f a x : 8 8 6 - 2 - 2 9 1 7 - 3 8 3 8 free datasheet http://www.datasheetlist.com/ |
Price & Availability of APW7070A
![]() |
|
|
All Rights Reserved © IC-ON-LINE 2003 - 2022 |
[Add Bookmark] [Contact Us] [Link exchange] [Privacy policy] |
Mirror Sites : [www.datasheet.hk]
[www.maxim4u.com] [www.ic-on-line.cn]
[www.ic-on-line.com] [www.ic-on-line.net]
[www.alldatasheet.com.cn]
[www.gdcy.com]
[www.gdcy.net] |