e l ek tr on isch e b a u e lemen te s q21 81 cmos positive voltage regulator * excellent psrr type 70 db * over-temperature shutdown * very low dropout voltage * factor pre-set output voltage * short circuit current fold-back * guaranteed 15 0ma output * current limiting * portable electronics applications * pc peripherals * wireless devices * battery powered widgets * electronic scales * instrumentation * cordless phones dimensions m i l l i m e t e r * power-saving shutdown mode f e a t u r e s have both thermal shutdown, and current fold-back to prevent device failure under the "worst" ofoperating conditions. as an additional feature, the sq21 81 is stable with an output capacitance of 2.2 m f or greater. description the s q 21 8 1 of positive, linear requlator feature low quiescent current (50 ma typ.) with low dropout voltage and excellent psrr, thus making them ideal for f or telecommunications and other battery applications. these rugged devices 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 . sq21 81 * noise reduction bypass capacitor * cameras * telecommunications * c ellular phones
h t t p : / / w w w . s e c o s g m b h . c o m / s q21 81 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 01-jun-2002 rev. a page 2 of 5 p s r r e n _ o u t p u t v o l t a g e n o i s e 7 0 3 0 _ d b u v r m s r o = 1 0 0 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 s h d n h i s d 0 . 0 1 _ _ _ _ _ g r o u n d p i n c u r r e n t s h d n i n p u t t h r e s h o l d i g n d 5 0 0 . 8 * v i n 0 0 . 5 0 1 0 . 4 _ u a u a v v v i n = 5 v , e n = 0 v , o r v i n = 5 v , v o = 0 v s h u t d o w n s u p p l y c u r r e n t v i n = 5 v , i o = 1 m a ~ 1 5 0 m a v s h d n l _ v i n 0 . 6 s h d n i n p u t b i a s c u r r e n t _ 5 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 , c o = 2 . 2 m f , f = 1 k h z v s h d n = 0 . 8 * v i n v s h d n = 0 . 6 v t c 1 3 7 n o t e v _ _ _ _ _ _ _ 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 3 5 . 5 2 3 3 0 _ _ c o c o p p m / c o - 0 . 4 0 . 4 v i n = v o u t ( t ) + 0 . 5 v ~ 5 . 5 v - 2 . 0 2 . 0 i o = 1 5 0 m a v o > 8 0 0 m v r e g l i n e l i n e r e g u l a t i o n i 6 0 - 0 . 2 a % v = 5 v , i o = 0 m a _ 0 . 2 i o = 0 . 1 m a , v o u t > 2 . 0 v v i n = v o u t ( t ) + 0 . 5 v ~ 5 . 5 v q u i e s c e n t c u r r e n t q 1 5 0 0 u i n _ 1 . 5 v v ( t ) < 1 . 8 v v o = v % m v _ 1 0 0 0 1 3 0 0 o u t o u t 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 u t i l i m v d r o p o u t - 1 . 5 1 5 0 - 1 v i o = 0 . 1 m a , v o u t ( t ) _ _ v o u t ( t ) 2 . 0 v 1 . 8 v v o u t ( t ) < 2 . 0 v 1 ( e ) v o u t 2 ( e ) 1 . 5 2 0 0 m a l o a d r e g u l a t i o n r e g l o a d 0 . 5 v o u t > 2 . 0 v , _ i o = 1 5 0 m a ( e ) - 2 % f o l d - b a c k c u r r e n t i f b _ _ 8 0 a u v o = 0 v v i n = v o u t ( t ) + 0 . 5 v v o u t 2 . 0 v , v i n = v o u t ( t ) + 1 . 0 v i o = 0 . 1 ~ 1 5 0 m a - 2 _ 2 3 0 0 7 0 0 9 0 0 _ i o = 0 . 1 m a , v o u t 2 . 0 v 0 . 1 o u t p u t l o a d i n g 1 2 0 0 [ , v o = 0 v [ ?? n o t e 1 : v o u t ( e ) = e f f e c t i v e o u t p u t v o l t a g e ( i . e . t h e o u t p u t v o l t a g e w h e n " v o u t ( t ) > 2 . 0 v , i s p r o v i d e d a t t h e v i n p i n w h i l e m a i n t a i n i n g a c e r t a i n i o u t v a l u e ) . 2 : v o u t ( t ) = s p e c i f i e d o u t p u t v o l t a g e 3 : v i n ( m i n ) = v o u t + v d r o p o u t v i n = v o u t ( t ) + 0 . 5 v ; v o u t ( t ) 2 . 0 v , v i n = v o u t ( t ) + 1 v ; v s h d n = v i n " i o = 0 . 1 m a , v o u t ( t ) < 2 . 0 v 2 . 0 v - 1 . 0 1 . 0 ( v o u t ( t ) > 2 . 0 v , v i n = v o u t ( t ) + 0 . 5 v ; v o u t ( t ) 2 . 0 v , v i n = v o u t ( t ) + 1 v ; v s h d n = v i n , c i n = c o u t = 1 u f ) 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 u n l e s s o t h e r w i s e n o t e d o c o c ) p o w e r d i s s i p a t i o n ( i n p u t v o l t a g e o u t p u t c u r r e n t o u t p u t v o l t a g e o p e r a t i n g a m b i e n t t e m p e r a t u r e j u n c t i o n t e m p e r a t u r e p a r a m e t e r s y m b o l r a t i n g s u n i t v m a v c m w v i n i o u t t j m a x . 6 p d / ( v i n - v o ) - 4 0 ~ + 1 2 5 - 4 0 ~ + 8 5 3 8 0 o m a x . j u n c t i o n t e m p e r a t u r e t = 1 0 0 e d s c l a s s i f i c a t i o n v o u t t o p r t j p d 1 5 0 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 1 . 5 ~ 3 . 3 ??
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 81 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 ordering information(contd.) detailed description the sq21 81 of coms regulators contain a pmos pass transistor,voltage reference, error amplifier,over-current protection and thermal shutdown. t h e p-channel pass transistor receives data from the error amplifier, over-current shutdown, and thermal protection circuits. during normal operation, the error amplifier compares the output voltage to a precision reference. over-current and thermal shutdown circuits become active when the junction temperature exceeds150 c, or the current exceeds 150ma. during thermal shutdown, the output voltage remains low. normal operation is restored when the junction temperature drops below 120 c . the sq21 81 switches from voltage mode to current mode when the load exceeds the rated output current. this prevents over-stress. the sq21 81 also incorporates o o current fold-back to reduce power dissipation when the output is short circuited. this feature becomes active when the output drops below 0.8 volts, and reduces the current flow by 65%. full current is restored when the voltage exceeds 0.8 volts. t h e s q 2 1 8 1 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 0 . 2 2 u f o r g r e a t e r. cera 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 . 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 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 " 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 . s h u t d o w n 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 e 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 . h a v e a b e n e f i c i a l e f f e c t . a l a r g e c a p a c i t o r i m p r o v e s t h e a c r i p p l e r e j e c t i o n , b u t a l s o m a k e s t h e o u t p u t c o m e u p s l o w l y . t h i s " s o f t " a l l t u r n - o n i s d e s i r a b l e i n s o m e a p p l i c a t i o n s t o l i m i t t u r n - o n s u r g e s . g r o u n d t e r m i n a t i o n e x t e r n a l c a p a c i t o r s c h a r a c t e r i s t i c s c u r v e s q 2 1 8 1 - 1 5 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 s q 2 1 8 1 - 2 0 s q 2 1 8 1 - 2 7 s q 2 1 8 1 - 2 h s q 2 1 8 1 - 3 2 1 l 1 5 2 1 . 5 v 2 . 0 v 2 . 7 v 2 . 8 5 v 3 . 2 v s q 2 1 8 1 - 1 8 s q 2 1 8 1 - 2 5 s q 2 1 8 1 - 2 8 s q 2 1 8 1 - 3 0 s q 2 1 8 1 - 3 3 1 . 8 v 2 . 5 v 2 . 8 v 3 . 0 v 3 . 3 v x x x x 1 l 2 0 2 x x x x 1 l 2 7 2 x x x x 1 l 2 h 2 x x x x 1 l 3 2 2 x x x x 1 l 1 8 2 x x x x 1 l 2 5 2 x x x x 1 l 2 8 2 x x x x 1 l 3 0 2 x x x x 1 l 3 3 2 x x x x
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 2 1 8 1 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 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 2 1 8 1 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
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