Rainbow Electronics W24256 - Manual

Preliminary W24256
32K
×
8 CMOS STATIC RAM
Publication Release Date: October 1999
- 1 - Revision A1
GENERAL DESCRIPTION
The W24256 is a normal speed, very low power CMOS static RAM organized as 32768
×
8 bits that
operates on a single 5-volt power supply. This device is manufactured using Winbond's high
performance CMOS technology.
FEATURES
• Low power consumption:
• Access time: 70 nS (max.)
•
Active :300 mW
Standby :250
µ
W
• Single 5V 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 28-pin 600 mil DIP, 330 mil SOP
and standard type one TSOP (8 mm
×
13.4
mm)
PIN CONFIGURATIONS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28-pin
DIP
28
27
26
25
24
23
22
21
20
19
18
17
16
15
V DD
WE
A13
A8
A9
A11
OE
A10
CS
I/O8
I/O7
I/O6
I/O5
I/O4
A14
A12
A7
A6
A5
A4
A3
A2
A1
A0
I/O1
I/O2
I/O3
V SS
1
2
3
4
5
6
7
8
9
10
11
12
13
14 28
27
26
25
24
23
22
21
20
19
18
17
16
15
28-pin
TSOP
OE
A11
A9
A8
A13
WE
V DD
A14
A12
A7
A6
A5
A4
A3
A10
CS
I/O8
I/O7
I/O6
I/O5
I/O4
I/O3
I/O2
I/O1
A0
A1
A2
V SS
BLOCK DIAGRAM
CLK GEN. PRECHARGE CKT.
CORE CELL ARRAY
512 ROWS
64 X 8 COLUMNS
DATA
CNTRL.
CLK
GEN.
R
O
W
D
E
C
O
D
E
R
A12
A14
A2
A3
A4
A5
A6
A7
A13
A11
I/O CKT.
COLUMN DECODER
OE
WE
CS
I/O1
I/O8
A10 A1 A0 A8 A9
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