S4008V1C
WCFS4008V1C
512K x 8 Static RAM
Features
• High speed
— t
AA
= 12 ns
• 2.0V Data Retention
• Automatic power-down when deselected
• TTL-compatible inputs and outputs
• Easy memory expansion with CE and OE features
Write Enable (WE) inputs LOW. Data on the eight I/O pins (I/O
0
through I/O
7
) is then written into the location specified on the
address pins (A
0
through A
18
).
Reading from the device is accomplished by taking Chip
Enable (CE) and Output Enable (OE) LOW while forcing Write
Enable (WE) HIGH. Under these conditions, the contents of
the memory location specified by the address pins will appear
on the I/O pins.
The eight input/output pins (I/O
0
through I/O
7
) are placed in a
high-impedance state when the device is deselected (CE
HIGH), the outputs are disabled (OE HIGH), or during a write
operation (CE LOW, and WE LOW).
The WCFS4008V1C is available in standard 400-mil-wide
36-pin SOJ package and 44-pin TSOP II package with center
power and ground pinout.
Functional Description
The WCFS4008V1C is a high-performance CMOS Static RAM
organized as 524K words by 8 bits. Easy memory expansion
is provided by an active LOW Chip Enable (CE), an active
LOW Output Enable (OE), and three-state drivers. Writing to
the device is accomplished by taking Chip Enable (CE) and
Logic Block Diagram
Pin Configuration
SOJ
Top View
TSOP II
Top View
NC
A
18
A
17
A
16
A
15
OE
I/O
7
I/O
6
GND
V
CC
I/O
5
I/O
4
A
14
A
13
A
12
A
11
A
10
NC
I/O
0
INPUT BUFFER
A
0
A
1
A
2
A
3
A
4
A
5
A
6
A
7
A
8
A
9
A
10
I/O
1
ROW DECODER
I/O
2
SENSE AMPS
512K x 8
ARRAY
I/O
3
I/O
4
I/O
5
CE
WE
OE
COLUMN
DECODER
POWER
DOWN
I/O
6
I/O
7
A
0
A
1
A
2
A
3
A
4
CE
I/O
0
I/O
1
V
CC
GND
I/O
2
I/O3
WE
A
5
A
6
A
7
A
8
A
9
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
NC
NC
A
0
A
1
A
2
A
3
A
4
CE
I/O
0
I/O
1
V
CC
V
SS
I/O
2
I/O
3
WE
A
5
A
6
A
7
A
8
A
9
NC
NC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
NC
NC
NC
A
18
A
17
A
16
A
15
OE
I/O
7
I/O
6
V
SS
V
CC
I/O
5
I/O
4
A
14
A
13
A
12
A
11
A
10
NC
NC
NC
Selection Guide
WCFS4008V1C 12ns
Maximum Access Time (ns)
Maximum Operating Current (mA)
Maximum CMOS Standby Current (mA)
Comm’l
Comm’l
12
85
10
A
11
A
12
A
13
A
14
A
15
A
16
A
17
A
18
WEIDA [ WEIDA SEMICONDUCTOR, INC. ]
