?top view c-mos 256 4 bits dynamic ram ********** LH64256BK-60
il08 input
a0 - a8
ras
cas
we
oe
input/output
i/o 1 - i/o 4
; address
; row address strobe
; column address strobe
; write enable (h : read, l : write)
; data output enable
; data 1
2
3
4
5
9
10
11
12
13 i/o1
i/o2
we
ras
a0
a1
a2
a3
nc
v dd(+5v) 26
25
24
23
22
18
17
16
15
14
i/o4
i/o3
cas
oe
a8
a7
a6
a5
a4 gnd 9
10
11
12
14
15
16
17
18
4
23
3
22 a0
a1
a2
a3
a4
a5
a6
a7
a8
ras
cas
we
oe 1
2
24
25 i/o 1
i/o 2
i/o 3
i/o 4 oe clock
generator r/w clock
generator sense amp.
i/o gate memory
array
1,048,576 bits data output
buffer data input
buffer address
buffer row
address
counter refresh
controller column decoder row decoder 1 2 24 25 i/o 1 i/o 2 i/o 3 i/o 4 9 a0 cas clock
generator ras clock
generator 22 oe 3 we 23 cas 4 ras 10 a1 11 a2 12 a3 14 a4 15 a5 16 a6 17 a7 18 a8
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