K4E661612D Datasheet, PDF (8/36 Pages) Samsung semiconductor – CMOS DRAM

Industrial Temperature
K4E661612D,K4E641612D
NOTES
CMOS DRAM
1 . A n i n i t i a l p a u s e o f 2 0 0 u s i s r e q u i r e d a f t e r p o w e r - u p f o l l o w e d b y a n y 8 R A S - o n l y o r C A S - b e f o r e -R A S r e f r e s h c y c l e s b e f o r e
proper device operation is achieved.
2 . I n p u t v o l t a g e l e v e l s a r e V i h / V i l . V IH ( m i n ) a n d V I L( m a x ) a r e r e f e r e n c e l e v e l s f o r m e a s u r i n g t i m i n g o f i n p u t s i g n a l s . T r a n s i t i o n
t i m e s a r e m e a s u r e d b e t w e e n V IH ( m i n ) a n d V IL ( m a x ) a n d a r e a s s u m e d t o b e 2 n s f o r a l l i n p u t s .
3 . Measured with a load equivalent to 1 TTL load and 100pF.
4 . O p e r a t i o n w i t h i n t h e t RCD( m a x ) l i m i t i n s u r e s t h a t tRAC ( m a x ) c a n b e m e t . tRCD ( m a x ) i s s p e c i f i e d a s a r e f e r e n c e p o i n t o n l y .
If t RCD i s g r e a t e r t h a n t h e s p e c i f i e d t RCD( m a x ) l i m i t , t h e n a c c e s s t i m e i s c o n t r o l l e d e x c l u s i v e l y b y tCAC .
5 . A s s u m e s t h a t t R C D≥t R C D( m a x ) .
6 . T h i s p a r a m e t e r d e f i n e s t h e t i m e a t w h i c h t h e o u t p u t a c h i e v e s t h e o p e n c i r c u i t c o n d i t i o n a n d i s n o t r e f e r e n c e d t o V o h o r V o l.
7 . t W C S, tR W D , tC W D a n d t A W D a r e n o n r e s t r i c t i v e o p e r a t i n g p a r a m e t e r s . T h e y a r e i n c l u d e d i n t h e d a t a s h e e t a s e l e c t r i c c h a r a c -
t e r i s t i c s o n l y . I f tW C S ≥tW C S( m i n ) , t h e c y c l e s i s a n e a r l y w r i t e c y c l e a n d t h e d a t a o u t p u t w i l l r e m a i n h i g h i m p e d a n c e f o r t h e
d u r a t i o n o f t h e c y c l e . I f tC W D ≥t C W D ( m i n ) , t R W D ≥t R W D( m i n ) a n d t AWD≥t A W D( m i n ) , t h e n t h e c y c l e i s a r e a d - m o d i f y - w r i t e c y c l e
and the data output will contain the data read from the selected address. If neither of the above conditions is satisfied, the
condition of the data out is indeterminate.
8 . E i t h e r tR C H o r t R R H m u s t b e s a t i s f i e d f o r a r e a d c y c l e .
9 . _{This parameters are referenced to theCAS leading edge in early write cycles and to theW falling edge in O E controlled write}
cycle and read-modify-write cycles.
1 0 . O p e r a t i o n w i t h i n t h e t R A D ( m a x ) l i m i t i n s u r e s t h a t tRAC ( m a x ) c a n b e m e t . tR A D ( m a x ) i s s p e c i f i e d a s a r e f e r e n c e p o i n t o n l y . I f
t RAD i s g r e a t e r t h a n t h e s p e c i f i e d t R A D ( m a x ) l i m i t , t h e n a c c e s s t i m e i s c o n t r o l l e d b y t A A.
11. _{These specifiecations are applied in the test mode.}
1 2 . I n t e s t m o d e r e a d c y c l e , t h e v a l u e o f t R A C , tA A , tCAC i s d e l a y e d b y 2 n s t o 5 n s f o r t h e s p e c i f i e d v a l u e s . T h e s e p a r a m e t e r s
should be specified in test mode cycles by adding the above value to the specified value in this data sheet.
1 3 . tASC, tCAH are referenced to the earlier C A S falling edge.
1 4 . tCP is specified from the last CAS rising edge in the previous cycle to the first C A S falling edge in the next cycle.
1 5 . tCWD is referenced to the later C A S falling edge at word read-modify-write cycle.
K4E64(6)1612D Truth Table
RAS
LCAS
UCAS
W
H
X
X
X
L
H
H
X
L
L
H
H
L
H
L
H
L
L
L
H
L
L
H
L
L
H
L
L
L
L
L
L
L
L
L
H
OE
DQ0 - DQ7
DQ8-DQ15
X
Hi-Z
Hi-Z
X
Hi-Z
Hi-Z
L
DQ-OUT
Hi-Z
L
Hi-Z
DQ-OUT
L
DQ-OUT
DQ-OUT
H
DQ-IN
-
H
-
DQ-IN
H
DQ-IN
DQ-IN
H
Hi-Z
Hi-Z
STATE
Standby
Refresh
Byte Read
Byte Read
Word Read
Byte Write
Byte Write
Word Write
-