e l ek tr on isch e b a u e lemen te s q21 31 cmos positive voltage regulator * power good output function f e a t u r e s * high accurate * over-temperature shutdown 3.0% * very low dropout voltage * low temperature coefficient * short circuit current fold-back * guaranteed 150ma output * current limiting * portable electronics applications * pc peripherals * wireless devices * battery powered widgets * electronic scales * instrumentation * cordless phones and current fold-back to prevent device failure under the "worst" of operating conditions. an additional feature is a "power good" detector, which pulls low when the output is out of regulation. the sq21 31 is stable with an output capacitance of 2.2mf or greater. 01 -jun-2002 rev. a page 1 of 5 http://www.secosgmbh.com/ any changing of specification will not be informed individual r o h s c o m p l i a n t p r o d u c t typical application circuit functional block diagram r e f . m i n . m a x . r e f . m i l l i m e t e r a 2 . 7 0 3 . 1 0 g 1 . 9 0 r e f . b 2 . 6 0 3 . 0 0 h 1 . 2 0 r e f . c 1 . 4 0 1 . 8 0 i 0 . 1 2 r e f . d 0 . 3 0 0 . 5 5 j 0 . 3 7 r e f . e 0 0 . 1 0 k 0 . 6 0 r e f . f 0 1 0 l 0 . 9 5 r e f . dimensions m i l l i m e t e r * power-saving shutdown mode description the sq21 31 is a fixed 1.2v of positive, linear regulators feature low quiescent current (60ma typ.) with low dropout voltage, making them ideal for battery applications. these rugged devices have both thermal shutdown, SQ2131 in out byp gnd en out in + c1 c2 1uf 2.2uf 5v
h t t p : / / w w w . s e c o s g m b h . c o m / s q21 31 c m o s p o s i t i v e v o l t a g e r e g u l a t o r e l e k t r o n i s c h e b a u e l e m e n t e a n y c h a n g i n g o f s p e c i f i c a t i o n w i l l n o t b e i n f o r m e d i n d i v i d u a l 1 p i n n u m b e r p i n n a m e p i n f u n c t i o n 2 3 4 5 s q 2 1 3 1 - 1 2 v i n g n d e n p g v o u t 1 . 2 v s u p p l y i n p u t g r o u n d e n a b l e / s h u t d o w n ( i n p u t ) : c m o s c o m p a t i b l e i n p u t l o g i c h i g h = e n a b l e ; l o g i c l o w = s h u t d o w n . d o n o t l e a v e o p e n r e g u l a t o r o u t p u t p o w e r g o o d o u t p u t 1 c 1 2 2 x x x x o r d e r i n g i n f o r m a t i o n ( c o n t d . ) p a r t n u m b e r m a r k i n g o u t p u t v o l t a g e p a r t n u m b e r m a r k i n g o u t p u t v o l t a g e p i n d e s c r i p t i o n 01-jun-2002 rev. a page 2 of 5 d e t a i l e d d e s c r i p t i o n t h e s q 2 1 3 1 o f c o m s r e g u l a t o r s c o n t a i n a p m o s p a s s t r a n s i s t o r , v o l t a g e r e f e r e n c e , e r r o r a m p l i f i e r , o v e r - c u r r e n t p r o t e c t i o n a n d t h e r m a l s h u t d o w n and power good function. t h e p - c h a n n e l p a s s t r a n s i s t o r r e c e i v e s d a t a f r o m t h e e r r o r a m p l i f i e r , o v e r - c u r r e n t s h u t d o w n , a n d t h e r m a l p r o t e c t i o n c i r c u i t s . d u r i n g n o r m a l o p e r a t i o n , t h e e r r o r a m p l i f i e r c o m p a r e s t h e o u t p u t v o l t a g e t o a p r e c i s i o n r e f e r e n c e . o v e r - c u r r e n t a n d t h e r m a l s h u t down c i r c u i t s b e c o m e a c t i v e 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 1 5 0 c , o r t h e c u r r e n t e x c e e d s 3 0 0 m a. d u r i n g t h e r m a l s h u t d o w n , t h e o u t p u t v o l t a g e r e m a i n s l o w . n o r m a l o p e r a t i o n i s r e s t o r e d 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 d r o p s b e l o w 1 2 0 c . t h e s q 2 1 3 1 s w i t c h e s f r o m v o l t a g e m o d e t o c u r r e n t m o d e w h e n t h e l o a d e x c e e d s t h e r a t e d o u t p u t c u r r e n t . t h i s p r e v e n t s o v e r - s t r e s s . t h e s q 2 1 3 1 a l s o i n corporates o o c u r r e n t f o l d - b a c k t o r e d u c e p o w e r d i s s i p a t i o n w h e n t h e o u t p u t i s s h o r t c i r c u i t e d . t h i s f e a t u r e b e c o m e s a c t i v e w h e n t h e o u t p u t d r o p s b e l o w 0 . 8 v o l t s , a n d r e d u c e s t h e c u r r e n t f l o w b y 6 5 % . f u l l c u r r e n t i s r e s t o r e d w h e n t h e v o l t a g e e x c e e d s 0 . 8 v o l t s . e x t e r n a l c a p a c i t o r s t h e s q 2 1 31 i s s t a b l e w i t h a n o u t p u t c a p a c i t a n c e t o g r o u n d o f 2 . 2 u f o r g r e a t e r . c e r a m i c c a p a c i t o r s h a v e t h e l o w e s t e s r , a n d w i l l o f f e r t h e b e s t a c p e r f o r m a n c e . c o n v e r s e l y , a l u m i n u m e l e r t r o l y t i c c a p a c i t o r s e x h i b i t t h e h i g h e s t e s r , r e s u l t i n g i n t h e p o o r e s t a c r e s p o n s e . u n f o r t u n a t e l y , l a r g e v a l u e c e r a m i c c a p a c i t o r s a r e c o m p a r a t i v e l y e x p e n s i v e . o n e o p t i o n i s t o p a r a l l e l a 0 . 1 u f c e r a m i c c a p a c i t o r w i t h a 1 0 u f a l u m i n u m e l e c t r o l y t i c . t h e b e n e f i t i s l o w e s r , h i g h c a p a c i t a n c e , a n d l o w o v e r a l l c o s t . a s e c o n d c a p a c i t o r i s r e c o m m e n d e d b e t w e e n t h e i n p u t a n d g r o u n d t o s t a b i l i z e v i n . t h e i n p u t c a p a c i t o r s h o u l d b e a t l e a s t 0 . 1 u f t o h a v e a b e n e f i c i a l e f f e c t . a l l c a p a c i t o r s s h o u l d b e p l a c e d i n c l o s e p r o x i m i t y t o t h e p i n s . a " q u i e t " g r o u n d t e r m i n a t i o n i s d e s i r a b l e . t h e c a n b e a c h i e v e d w i t h a " s t a r " c o n n e c t i o n . e n a b l e t h e e n a b l e p i n n o r m a l l y f l o a t s h i g h . w h e n a c t i v e l y , p u l l e d l o w , t h e p m o s p a s s t r a n s i s t o r s h u t s o f f , a n d a l l i n t e r n a l c i r c u i t s a r e p o w e r e d d o w n . i n t h i s s t a t e , t h e q u i e s c e n t c u r r e n t i s l e s s t h a n 1 u a . t h i s p i n b e h a v e s m u c h l i k e a n e l e c t r o n i c s w i t c h . fig 1. typical application schematic fig 2. typical application for processor vid code power sequencing schematic SQ2131 SQ2131
01-jun-2002 rev. a page 3 of 5 h t t p : / / w w w .s e c o sg m b h .c o m/ a n y c ha n g i n g o f s pe c if i c a t i o n w ill no t b e i n f o r m ed i nd i v i dual e l e k t r o n i s c h e b a u e l e m e n t e s q 2 1 31 c m o s p o s i t i v e v o l t a g e r e g u l a t o r % v o ( n o m ) p s r r e n 1 . 5 v _ _ _ _ _ _ _ o u t p u t v o l t a g e n o i s e 5 0 2 0 1 5 3 0 _ _ _ _ d b u v r m s f = 1 0 0 h z f = 1 k h z f = 1 0 k h z c o = 2 . 2 u f i o = 1 0 0 m a c o = 2 . 2 u f f = 1 0 h z ~ 1 0 0 k h z i o = 1 0 m a p o w e r s u p p l y r e j e c t i o n v e h i e h i s d 0 . 1 _ _ _ _ _ _ o u t p u t u n d e r v o l t a g e e n i n p u t t h r e s h o l d v u v 9 5 1 . 6 0 0 . 1 0 . 5 0 1 0 . 4 _ _ u a v v v e n = v i n v i n = 5 v , v o = 0 v , v e n = 0 v o u t p u t l o a d i n g 1 2 0 0 [ , v e n = 0 v s h u t d o w n s u p p l y c u r r e n t v e l _ v i n 0 . 4 e n i n p u t b i a s c u r r e n t i e l _ v e n = 0 v s h u t d o w n o u t p u t v o l t a g e v o , s d u a p g v o l t a g e l o w v p g d e l a y v o l t p g d * n o t e 1 : v = v + v 0 . 1 5 i s i n k = 0 . 1 m a m s s e e t i m i n g d i a g r a m o n p a g e 5 p g o n @ % o f v o u t t c i n p u t v o l t a g e o v e r t e m p e r a t u r e s h u t d o w n o v e r t e m p e r a t u r e h y s t e r s i s o u t p u t v o l t a g e t e m p e r a t u r e c o e f f i c i e n t v i n o t s o t h r e g l i n e l i n e r e g u l a t i o n 3 0 _ 1 5 0 _ % _ _ 0 . 3 6 i o = 0 . 1 m a , v i n = 2 . 7 v - 0 . 3 t o 6 v c o 0 . 1 p g l e a k a g e c u r r e n t i l c 2 . 7 v _ _ _ c o 3 0 _ p p m / c o _ _ u a v p g = 6 v , p g i s o f f 6 5 _ v i n = 6 v , i o = 1 m a g r o u n d p i n c u r r e n t i g n d a u t o 1 5 0 m a i q u i e s c e n t c u r r e n t q _ 8 0 _ 6 0 a u v i n = 6 v , i o = 0 m a , v o = v o ( n o m ) 4 % p a r a m e t e r s y m b o l m a x . t y p . c o n d i t i o n m i n . u n i t o u t p u t v o l t a g e c u r r e n t l i m i t d r o p o u t v o l t a g e v o i l i m v d r o p o u t - 3 . 0 % 1 5 0 - 4 i o = 0 . 1 m a _ 3 . 0 % 3 5 0 m a l o a d r e g u l a t i o n r e g l o a d 1 io=0.1ma vo<0.1v 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 = 2 5 v i n = 2 . 7 v , v e n = v i n , i o = 1 0 0 u a u n l e s s o t h e r w i s e n o t e d c _ v o in(min) out dropout to 150ma 1 3 0 0 _ _ m v io=150ma,v out =vo-2% o c) power dissipation ( input voltage output current iutput,output voltage operating ambient temperature junction temperature parameter symbo l ratings unit v ma v c mw v in i out tj max. 7 p d /(v in -v o ) -40~+125 gnd-0.3 to v in +0.3 -40~+85 380 o max. junction temperature t=100 eds classification topr tj p d 150 b c o c o a b s o l u t e m a x i m u m r a t i n g s thermal resistance q ja 260 c o /w p o w e r g o o d t h e s q 2 1 3 1 i n c l u d e s t h e p o w e r g o o d f e a t u r e . w h e n t h e o u t p u t i s n o t w i t h i n 1 5 % o f t h e s p e c i f i e d v o l t a g e , i t p u l l s l o w . t h i s c a n o c c u r u n d e r t h e f o l l o w i n g c o n d i t i o n s : 1 . i n p u t v o t a g e t o o l o w . 2 . d u r i n g o v e r - t e m p e r a t u r e . 3 . d u r i n g o v e r - c u r r e n t . 1 . i f o u t p u t i s p u l l e d u p . ( n o t e : p g p i n i s a n o p e n - d r a i n o u t p u t . )
e l ek tr on isch e b a u e lemen te 01 -jun-2002 rev. a page 4 of 5 http://www.secosgmbh.com/ any changing of specification will not be informed individual s q 21 31 cmos positive voltage regulator c h a r a c t e r i s t i c s c u r v e
e l e k t r o n i s c h e b a u e l e m e n t e h t t p : / / w w w . s e c o s g m b h . c o m / a n y c h a n g i n g o f s p e c i f i c a t i o n w i l l n o t b e i n f o r m e d i n d i v i d u a l 01-jun-2002 rev. a page 5 of 5 s q 21 31 cmos positive voltage regulator t i m i n g d i a g r a m
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