Rainbow Electronics W24257 - Manual

W24257
32K × 8 CMOS STATIC RAM
Publication Release Date: April 1997
- 1 - Revision A11
8GENERAL DESCRIPTION
The W24257 is a slow speed, 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:
− Active: 400 mW (max.)
− Standby: 250
µ
W (max.) (LL-version)
500
µ
W (max.) (L-version)
• Access time: 70/100 nS (max.)
• 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.)
• Available packages: 28-pin 600 mil DIP, 330
mil SOP, 300 mil skinny DIP and SOJ
PIN CONFIGURATION
25
26
27
28
20
21
22
23
16
17
18
19
15
A8
A9
A11
A10
I/O8
I/O7
I/O6
I/O5
I/O4
A13
CS
OE
WE
V DD
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A14
A7
A6
A5
A12
A4
A3
A2
A1
A0
I/O2
I/O3
I/O1
V SS
24
BLOCK DIAGRAM
A0
.
.
CS
A14
WE
I/O1
I/O8
OE
V DD
V SS
.
.
DATA I/O
DECODER
CONTROL
CORE
ARRAY
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