Rainbow Electronics W24L257 User Manual
General description, Features, Pin configurations block diagram
Preliminary W24L257
32K
× 8 CMOS STATIC RAM
Publication Release Date: May 2000
- 1 -
Revision A1
GENERAL DESCRIPTION
The W24L257 is a normal-speed, very low-power CMOS static RAM organized as 32768
× 8 bits that
operates on a wide voltage range from 3.0V to 3.6V power supply. This device is manufactured using
Winbond's high performance CMOS technology.
FEATURES
•
Low power consumption:
−
Active: 126 mW (max.)
•
Access time: 70 nS
•
Single 3.3V power supply
•
Fully static operation
•
All inputs and outputs directly TTL compatible
•
Three-state outputs
•
Battery back-up operation capability
•
Data retention voltage: 2V (min.)
•
Packaged in 450 mil SOP, standard type one
TSOP (8 mm
× 20 mm) ,
PIN CONFIGURATIONS
BLOCK DIAGRAM
1
2
3
4
5
6
7
8
9
10
11
12
13
16
24
25
26
27
28
20
21
22
23
17
18
19
14
15
A8
A9
WE
A11
OE
A10
CS
I/O8
I/O7
I/O6
I/O5
I/O4
A13
VCC
A7
A6
A5
A12
A4
A3
A2
A1
A0
I/O2
I/O3
I/O1
V
A14
SS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28-pin
TSOP
15
16
28
27
26
25
24
23
22
21
20
19
18
17
A12
A7
A6
A5
A4
A8
V
DD
A11
A9
A14
A13
WE
A3
A2
A1
A0
OE
A10
CS
I/O7
I/O6
I/O5
I/O4
I/O8
V
SS
I/O3
I/O2
I/O1
CORE CELL ARRAY
512 ROWS
32 X 8 COLUMNS
DATA
CNTRL
.
CLK
GEN.
R
O
W
D
E
C
O
D
E
R
I/O CKT.
COLUMN DECODER
WE
OE
CLK GEN.
PRECHARGE CKT.
A13
A8
A1 A0
A11 A10
CS
A14
A12
A4
A3
A2
A7
A6
A5
A9
I/O1
I/O8
:
PIN DESCRIPTION
SYMBOL DESCRIPTION
A0
−A14
Address Inputs
I/O1
−I/O8
Data Inputs/Outputs
CS
Chip Select Input
WE
Write Enable Input
OE
Output Enable Input
V
DD
Power
Supply
V
SS
Ground
NC No
Connection