W24257A
32K
×
8 HIGH SPEED CMOS STATIC RAM
GENERAL DESCRIPTION
The W24257A is a high 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
•
•
•
•
High speed access time: 10/12/15/20 nS (max.)
Low power consumption:
−
Active: 400 mW (typ.)
Single
+5V
power supply
Fully static operation
•
•
•
All inputs and outputs directly TTL compatible
Three-state outputs
Available packages: 28-pin 300 mil SOJ, 330
mil SOP, skinny DIP and standard type one
TSOP (8 mm
×
13.4 mm)
PIN CONFIGURATIONS
BLOCK DIAGRAM
V
DD
V
SS
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-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
A0
.
.
A14
DECODER
CORE
ARRAY
CS
OE
WE
CONTROL
DATA I/O
I/O1
.
.
I/O8
PIN DESCRIPTION
OE
A11
A9
A8
A13
WE
V
DD
A14
A12
A7
A6
A5
A4
A3
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
A10
CS
I/O8
I/O7
I/O6
I/O5
I/O4
V
SS
I/O3
I/O2
I/O1
A0
A1
A2
28-pin
TSOP
SYMBOL
A0−A14
I/O1−I/O8
CS
WE
OE
V
DD
V
SS
DESCRIPTION
Address Inputs
Data Inputs/Outputs
Chip Select Input
Write Enable Input
Output Enable Input
Power Supply
Ground
-1-
Publication Release Date: May 1997
Revision A14
W24257A
DC CHARACTERISTICS
Absolute Maximum Ratings
PARAMETER
Supply Voltage to V
SS
Potential
Input/Output to V
SS
Potential
Allowable Power Dissipation
Storage Temperature
Operating Temperature
RATING
-0.5 to +7.0
-0.5 to V
DD
+0.5
1.0
-65 to +150
0 to +70
UNIT
V
V
W
°C
°C
Note: Exposure to conditions beyond those listed under Absolute Maximum Ratings may adversely affect the life and reliability of the
device.
TRUTH TABLE
CS
H
L
L
L
OE
X
H
L
X
WE
X
H
H
L
MODE
Not Selected
Output Disable
Read
Write
I/O1−I/O8
High Z
High Z
Data Out
Data In
V
DD
CURRENT
I
SB
, I
SB1
I
DD
I
DD
I
DD
OPERATING CHARACTERISTICS
(V
DD
= 5V
±10%,
V
SS
= 0V, T
A
= 0 to 70° C)
PARAMETER
Input Low Voltage
Input High Voltage
Input Leakage Current
Output Leakage
Current
Output Low Voltage
Output High Voltage
Operating Power
Supply Current
SYM.
V
IL
V
IH
I
LI
I
LO
V
OL
V
OH
I
DD
TEST CONDITIONS
-
-
V
IN
= V
SS
to V
DD
V
I/O
= V
SS
to V
DD,
CS = V
IH
or OE = V
IH
or WE = V
IL
I
OL
= +8.0 mA
I
OH
= -4.0 mA
10
CS = V
IL,
I/O = 0 mA
Cycle = MIN
Duty = 100%
12
15
20
MIN.
-0.5
+2.2
-10
-10
-
2.4
-
-
-
-
-
TYP.
-
-
-
-
-
-
-
-
-
-
-
MAX.
+0.8
V
DD
+0.5
+10
+10
0.4
-
170
160
150
140
30
10
UNIT
V
V
µA
µA
V
V
mA
mA
mA
mA
mA
mA
Standby Power
Supply Current
I
SB
I
SB1
CS = V
IH
Cycle = MIN, Duty = 100%
CS
≥
V
DD
-0.2V
Note: Typical characteristics are at V
DD
= 5V, T
A
= 25° C.
-2-
W24257A
CAPACITANCE
(V
DD
= 5V, T
A
= 25° C, f = 1 MHz)
PARAMETER
Input Capacitance
Input/Output Capacitance
SYM.
C
IN
C
I/O
CONDITIONS
V
IN
= 0V
V
OUT
= 0V
MAX.
8
10
UNIT
pF
pF
Note: These parameters are sampled but not 100% tested.
THERMAL RESISTANCE
PARAMETER
Junction to Case Thermal Resistance
Junction to Ambient Thermal
Resistance
SYM
.
CONDITIONS
A. F. R. = 1m/sec, T
A
= 25° C
A. F. R. = 1m/sec, T
A
= 25° C
MAX.
20
60
UNIT
°C/W
°C/W
θ
JC
θ
JA
Note: These parameters are only applied to "TSOP" and "SOJ" package types.
AC TEST CONDITIONS
PARAMETER
Input Pulse Levels
Input Rise and Fall Times
Input and Output Timing Reference Level
Output Load
0V to 3V
5 nS
1.5V
C
L
= 30 pF, I
OH
/I
OL
= -4 mA/8 mA
CONDITIONS
-3-
Publication Release Date: May 1997
Revision A14
W24257A
AC TEST LOADS AND WAVEFORM
R1 480 ohm
R1 480 ohm
5V
OUTPUT
30 pF
Including
Jig and
Scope
R2
255 ohm
5V
OUTPUT
5 pF
Including
Jig and
Scope
R2
255 ohm
(For T
CLZ
, T
OLZ
, T
CHZ
, T
OHZ
, T
WHZ
, T
OW
)
3.0V
90%
10%
5 nS
90%
10%
5 nS
0V
-4-
W24257A
AC CHARACTERISTICS
(V
DD
= 5V
±10%,
V
SS
= 0V, T
A
= 0 to 70° C)
Read Cycle
PARAMETER
SYM.
W24257A-10
MIN.
Read Cycle Time
Address Access Time
Chip Select Access Time
Output Enable to Output Valid
Chip Selection to Output in Low Z
Output Enable to Output in Low Z
Chip Deselection to Output in High Z
Output Disable to Output in High Z
Output Hold from Address Change
T
RC
T
AA
T
ACS
T
AOE
T
CLZ
∗
T
OLZ
∗
T
CHZ
∗
T
OHZ
∗
T
OH
10
-
-
-
3
0
-
-
3
MAX.
-
10
10
5
-
-
5
5
-
W24257A-12
MIN.
12
-
-
-
3
0
-
-
3
MAX.
-
12
12
6
-
-
6
6
-
W24257A-15
MIN.
15
-
-
-
3
0
-
-
3
MAX.
-
15
15
7
-
-
7
7
-
W24257A-20
MIN.
20
-
-
-
3
0
-
-
3
MAX.
-
20
20
10
-
-
10
10
-
nS
nS
nS
nS
nS
nS
nS
nS
nS
UNIT
∗
These parameters are sampled but not 100% tested.
Write Cycle
PARAMETER
SYM.
W24257A-10
MIN.
Write Cycle Time
Chip Selection to End of Write
Address Valid to End of Write
Address Setup Time
Write Pulse Width
Write Recovery Time
Data Valid to End of Write
Data Hold from End of Write
Write to Output in High Z
Output Disable to Output in High Z
Output Active from End of Write
CS , WE
T
WC
T
CW
T
AW
T
AS
T
WP
T
WR
T
DW
T
DH
T
WHZ
∗
T
OHZ
∗
T
OW
10
9
9
0
9
0
6
0
-
-
0
MAX.
-
-
-
-
-
-
-
-
6
6
-
W24257A-12
MIN.
12
10
10
0
10
0
7
0
-
-
0
MAX.
-
-
-
-
-
-
-
-
7
7
-
W24257A-15
MIN.
15
13
13
0
10
0
9
0
-
-
0
MAX.
-
-
-
-
-
-
-
-
8
8
-
W24257A-20
MIN.
20
17
17
0
12
0
10
0
-
-
0
MAX.
-
-
-
-
-
-
-
-
10
10
-
nS
nS
nS
nS
nS
nS
nS
nS
nS
nS
nS
UNIT
∗
These parameters are sampled but not 100% tested.
-5-
Publication Release Date: May 1997
Revision A14
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