87
CY7C187
64K x 1 Static RAM
vided by an active LOW Chip Enable (CE) and three-state driv-
ers. The CY7C187 has an automatic power-down feature,
reducing the power consumption by 56% when deselected.
Features
• High speed
— 15 ns
Writing to the device is accomplished when the Chip Enable
(CE) and Write Enable (WE) inputs are both LOW. Data on the
input pin (DIN) is written into the memory location specified on
the address pins (A0 through A15).
• CMOS for optimum speed/power
• Low active power
— 495 mW
Reading the device is accomplished by taking the Chip Enable
(CE) LOW, while Write Enable (WE) remains HIGH. Under
these conditions, the contents of the memory location speci-
• Low standby power
— 220 mW
fied on the address pin will appear on the data output (DOUT
pin.
)
• TTL compatible inputs and outputs
• Automatic power-down when deselected
The output pin stays in high-impedance state when Chip En-
able (CE) is HIGH or Write Enable (WE) is LOW.
Functional Description
The CY7C187 utilizes a die coat to insure alpha immunity.
The CY7C187 is a high-performance CMOS static RAM orga-
nized as 65,536 words x 1 bit. Easy memory expansion is pro-
Logic Block Diagram
Pin Configurations
SOJ
Top View
DIP
Top View
DI
A
V
CC
1
22
A
V
0
0
CC
1
24
A
1
A
A
2
3
4
21
20
19
18
17
16
15
A
1
A
A
15
15
2
3
4
23
22
21
20
19
18
17
INPUT BUFFER
A
A
2
14
2
14
A
3
A
A
A
3
A
A
13
13
A
4
5
6
A
12
4
12
5
6
7
8
9
10
11
12
A
12
A
5
A
11
A
10
A
9
A
NC
5
NC
A
A
13
7
8
9
10
11
A
11
6
A
7
A
6
A
15
A
A
A
10
14
D
14
13
12
A
9
OUT
A
256 x 256
ARRAY
A
7
16
15
A
8
DO
CE
D
D
IN
WE
OUT
WE
A
8
D
0
1
CE
GND
IN
14
13
GND
CE
A
3
2
A
C187–3
C187–2
POWER
DOWN
COLUMN DECODER
WE
C187–1
Selection Guide[1]
7C187-15
15
7C187-20
20
7C187-25
25
7C187-35
35
Maximum Access Time (ns)
Maximum Operating Current (mA)
90
80
70
70
Maximum Standby Current (mA)
40/20
40/20
20/20
20/20
Note:
1. For military specifications, see the CY7C187A datasheet.
Cypress Semiconductor Corporation
•
3901 North First Street
•
San Jose
•
CA 95134
•
408-943-2600
Document #: 38-05044 Rev. **
Revised August 24, 2001