W24257A
32K
8 HIGH SPEED CMOS STATIC RAM
Publication Release Date: May 1997
- 1 -
Revision A14
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
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
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
W24257A
- 2 -
DC CHARACTERISTICS
Absolute Maximum Ratings
PARAMETER
RATING
UNIT
Supply Voltage to V
SS
Potential
-0.5 to +7.0
V
Input/Output to V
SS
Potential
-0.5 to V
DD
+0.5
V
Allowable Power Dissipation
1.0
W
Storage Temperature
-65 to +150
C
Operating Temperature
0 to +70
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
OE
WE
MODE
I/O1
-
I/O8
V
DD
CURRENT
H
X
X
Not Selected
High Z
I
SB
, I
SB1
L
H
H
Output Disable
High Z
I
DD
L
L
H
Read
Data Out
I
DD
L
X
L
Write
Data In
I
DD
OPERATING CHARACTERISTICS
(V
DD
= 5V
10%, V
SS
= 0V, T
A
= 0 to 70
C)
PARAMETER
SYM.
TEST CONDITIONS
MIN.
TYP.
MAX.
UNIT
Input Low Voltage
V
IL
-
-0.5
-
+0.8
V
Input High Voltage
V
IH
-
+2.2
-
V
DD
+0.5
V
Input Leakage Current
I
LI
V
IN
= V
SS
to V
DD
-10
-
+10
A
Output Leakage
Current
I
LO
V
I/O
= V
SS
to V
DD,
CS = V
IH
or OE = V
IH
or WE = V
IL
-10
-
+10
A
Output Low Voltage
V
OL
I
OL
= +8.0 mA
-
-
0.4
V
Output High Voltage
V
OH
I
OH
= -4.0 mA
2.4
-
-
V
Operating Power
I
DD
CS = V
IL,
I/O = 0 mA
10
-
-
170
mA
Supply Current
Cycle = MIN
12
-
-
160
mA
Duty = 100%
15
150
mA
20
-
-
140
mA
Standby Power
Supply Current
I
SB
CS = V
IH
Cycle = MIN, Duty = 100%
-
-
30
mA
I
SB1
CS
V
DD
-0.2V
-
-
10
mA
Note: Typical characteristics are at V
DD
= 5V, T
A
= 25
C.
W24257A
Publication Release Date: May 1997
- 3 -
Revision A14
CAPACITANCE
(V
DD
= 5V, T
A
= 25
C, f = 1 MHz)
PARAMETER
SYM.
CONDITIONS
MAX.
UNIT
Input Capacitance
C
IN
V
IN
= 0V
8
pF
Input/Output Capacitance
C
I/O
V
OUT
= 0V
10
pF
Note: These parameters are sampled but not 100% tested.
THERMAL RESISTANCE
PARAMETER
SYM
.
CONDITIONS
MAX.
UNIT
Junction to Case Thermal Resistance
JC
A. F. R. = 1m/sec, T
A
= 25
C
20
C/W
Junction to Ambient Thermal
Resistance
JA
A. F. R. = 1m/sec, T
A
= 25
C
60
C/W
Note: These parameters are only applied to "TSOP" and "SOJ" package types.
AC TEST CONDITIONS
PARAMETER
CONDITIONS
Input Pulse Levels
0V to 3V
Input Rise and Fall Times
5 nS
Input and Output Timing Reference Level
1.5V
Output Load
C
L
= 30 pF, I
OH
/I
OL
= -4 mA/8 mA
W24257A
- 4 -
AC TEST LOADS AND WAVEFORM
90%
90%
5 nS
10%
5 nS
10%
R1 480 ohm
5V
OUTPUT
R2
255 ohm
5 pF
R2
255 ohm
R1 480 ohm
5V
OUTPUT
30 pF
Including
Jig and
Scope
3.0V
0V
Including
Jig and
Scope
)
(For T
CLZ
,
,
,
,
,
T
OLZ
T
CHZ
T
OHZ
T
WHZ
T
OW
W24257A
Publication Release Date: May 1997
- 5 -
Revision A14
AC CHARACTERISTICS
(V
DD
= 5V
10%, V
SS
= 0V, T
A
= 0 to 70
C)
Read Cycle
PARAMETER
SYM.
W24257A-10
W24257A-12
W24257A-15
W24257A-20
UNIT
MIN.
MAX.
MIN.
MAX.
MIN.
MAX.
MIN.
MAX.
Read Cycle Time
T
RC
10
-
12
-
15
-
20
-
nS
Address Access Time
T
AA
-
10
-
12
-
15
-
20
nS
Chip Select Access Time
T
ACS
-
10
-
12
-
15
-
20
nS
Output Enable to Output Valid
T
AOE
-
5
-
6
-
7
-
10
nS
Chip Selection to Output in Low Z
T
CLZ
3
-
3
-
3
-
3
-
nS
Output Enable to Output in Low Z
T
OLZ
0
-
0
-
0
-
0
-
nS
Chip Deselection to Output in High Z
T
CHZ
-
5
-
6
-
7
-
10
nS
Output Disable to Output in High Z
T
OHZ
-
5
-
6
-
7
-
10
nS
Output Hold from Address Change
T
OH
3
-
3
-
3
-
3
-
nS
These parameters are sampled but not 100% tested.
Write Cycle
PARAMETER
SYM.
W24257A-10
W24257A-12
W24257A-15
W24257A-20
UNIT
MIN.
MAX.
MIN.
MAX.
MIN.
MAX.
MIN.
MAX.
Write Cycle Time
T
WC
10
-
12
-
15
-
20
-
nS
Chip Selection to End of Write
T
CW
9
-
10
-
13
-
17
-
nS
Address Valid to End of Write
T
AW
9
-
10
-
13
-
17
-
nS
Address Setup Time
T
AS
0
-
0
-
0
-
0
-
nS
Write Pulse Width
T
WP
9
-
10
-
10
-
12
-
nS
Write Recovery Time
CS , WE
T
WR
0
-
0
-
0
-
0
-
nS
Data Valid to End of Write
T
DW
6
-
7
-
9
-
10
-
nS
Data Hold from End of Write
T
DH
0
-
0
-
0
-
0
-
nS
Write to Output in High Z
T
WHZ
-
6
-
7
-
8
-
10
nS
Output Disable to Output in High Z
T
OHZ
-
6
-
7
-
8
-
10
nS
Output Active from End of Write
T
OW
0
-
0
-
0
-
0
-
nS
These parameters are sampled but not 100% tested.
W24257A
- 6 -
TIMING WAVEFORMS
Read Cycle 1
(Address Controlled)
Address
T
RC
T
AA
T
OH
T
OH
D
OUT
Read Cycle 2
(Chip Select Controlled)
CS
D
OUT
T
CLZ
T
ACS
CHZ
T
Read Cycle 3
(Output Enable Controlled)
Address
T
RC
CS
D
OUT
T
AA
OE
T
AOE
T
OLZ
T
OH
CLZ
T
CHZ
T
T
ACS
T
OHZ
W24257A
Publication Release Date: May 1997
- 7 -
Revision A14
Timing Waveforms, continued
Write Cycle 1
(OE Clock)
Address
OE
CS
WE
D
OUT
D
IN
T
WC
T
WR
T
CW
T
WP
T
AS
T
OHZ
(1, 4)
T
DW
T
DH
T
AW
Write Cycle 2
(OE = V
IL
Fixed)
Address
CS
WE
D
OUT
D
IN
T
WC
T
CW
T
AS
T
DH
T
WR
T
WP
T
WHZ
DW
T
(2)
(3)
T
OW
T
OH
AW
T
(1, 4)
Notes:
1. During this period, I/O pins are in the output state, so input signals of opposite phase to the outputs should not be applied.
2. The data output from D
OUT
are the same as the data written to D
IN
during the write cycle.
3. D
OUT
provides the read data for the next address.
4. Transition is measured
500 mV from steady state with C
L
= 5 pF. This parameter is guaranteed but not 100% tested.
W24257A
- 8 -
ORDERING INFORMATION
PART NO.
ACCESS
TIME
(nS)
OPERATING
CURRENT
MAX. (mA)
STANDBY
CURRENT
MAX. (mA)
PACKAGE
W24257AK-10
10
170
10
300 mil skinny DIP
W24257AK-12
12
160
10
300 mil skinny DIP
W24257AK-15
15
150
10
300 mil skinny DIP
W24257AK-20
20
140
10
300 mil skinny DIP
W24257AJ-10
10
170
10
300 mil SOJ
W24257AJ-12
12
160
10
300 mil SOJ
W24257AJ-15
15
150
10
300 mil SOJ
W24257AJ-20
20
140
10
300 mil SOJ
W24257AS-10
10
170
10
330 mil SOP
W24257AS-12
12
160
10
330 mil SOP
W24257AS-15
15
150
10
330 mil SOP
W24257AS-20
20
140
10
330 mil SOP
W24257AQ-10
10
170
10
Standard type one TSOP
W24257AQ-12
12
160
10
Standard type one TSOP
W24257AQ-15
15
150
10
Standard type one TSOP
W24257AQ-20
20
140
10
Standard type one TSOP
Notes:
1. Winbond reserves the right to make changes to its products without prior notice.
2. Purchasers are responsible for performing appropriate quality assurance testing on products intended for use in
applications where personal injury might occur as a consequence of product failure.
W24257A
Publication Release Date: May 1997
- 9 -
Revision A14
PACKAGE DIMENSIONS
28-pin P-DIP Skinny
1. Dimensions D Max. & S include mold flash or
tie bar burrs.
2. Dimension E1 does not include interlead flash.
3. Dimensions D & E1 include mold mismatch and
are determined at the mold parting line.
6. General appearance spec. should be based on
final visual inspection spec.
1.63
1.47
0.064
0.058
Notes:
Symbol
Min. Nom. Max.
Max.
Nom.
Min.
Dimension in Inches
Dimension in mm
A
B
c
D
e
A
L
S
A
A
1
2
E
0.060
1.52
0.175
4.45
0.010
0.125
0.016
0.130
0.018
0.135
0.022
3.18
0.41
0.25
3.30
0.46
3.43
0.56
0.008
0.120
0.370
0.010
0.130
0.014
0.140
0.20
3.05
0.25
3.30
0.36
3.56
0.293
0.288
0.283
7.44
7.32
7.19
9.40
7.87
7.62
8.13
0.310
0.300
0.320
2.29
2.54
2.79
0.090
0.100
0.110
B
1
1
e
E
1
a
1.388
1.400
35.26
35.56
0
15
0.055
1.40
0.350
0.330
8.38
8.89
15
0
4. Dimension B1 does not include dambar
protrusion/intrusion.
5. Controlling dimension: Inches.
e
A
A
a
c
E
Base Plane
Mounting Plane
1
A
1
e
L
A
S
1
E
D
1
B
B
28
15
1
14
2
28-pin Small Outline J Band
1
y
1
e
s
1
b
b
c
L
e
Seating Plane
1
2
A
A
A
D
E
H
E
14
15
28
c
0.36
0.20
0.014
0.008
Symbol
Min. Nom. Max.
Max.
Nom.
Min.
Dimension in Inches
Dimension in mm
A
b
c
D
e
H
E
L
y
A
A
S
1
1
2
E
0.010
0.25
0.140
3.56
0.027
0.095
0.016
0.100
0.018
0.105
0.022
2.41
0.41
0.69
2.54
0.46
2.67
0.56
0.077
0.004
0
10
0.710
0.087
0.730
0.097
1.96
18.03
2.21
18.54
2.46
0.285
0.265
0.245
7.24
6.73
6.22
0
0.10
7.75
7.62
7.49
0.305
0.300
0.295
8.31
8.56
8.81
0.327
0.337
0.347
1. Dimensions D Max. & S include mold flash
or tie bar burrs.
2. Dimension b does not include dambar
protrusion/intrusion.
4. Controlling dimension: Inches.
5. General appearance spec. should be based
on final visual inspection spec.
Notes:
3. Dimensions D & E include mold mismatch
and are determined at the mold parting line.
e
b
1
0.81
0.71
0.66
0.032
0.028
0.026
0.044
0.050
0.056
1.12
1.27
1.42
0.045
1.14
10
W24257A
- 10 -
Package Dimensions, continued
28-pin SO Wide Body
2
1
A
28
15
14
1
e
S
E
H
b
Seating Plane
A A
y
L
L
e
c
See Detail F
D
E
E
1
1
e
Detail F
1. Dimensions D Max. & S include mold flash
or tie bar burrs.
2. Dimension b does not include dambar
protrusion/intrusion.
3. Dimensions D & E include mold mismatch
and are determined at the mold parting line.
.
0.25
0.20
0.010
0.008
Notes:
Symbol
Min. Nom.
Max.
Max.
Nom.
Min.
Dimension in Inches
Dimension in mm
A
b
c
D
e
H
E
L
y
A
A
L
E
1
2
E
0.014
0.36
0.112
2.85
0.004
0.093
0.014
0.098
0.016
0.103
0.020
2.36
0.36
0.10
2.49
0.41
2.62
0.51
0.059
0.004
0
10
0.713
0.067
0.733
0.075
1.50
18.11
1.70
18.62
1.91
0.477
0.465
0.453
12.12
11.81
11.51
10
0
0.10
8.53
8.41
8.28
0.336
0.331
0.326
0.71
0.91
1.12
0.028
0.036
0.044
4. Controlling dimension: Inches.
5. General appearance spec should be based
on final visual inspection spec.
1.12
1.27
1.42
0.044
0.050
0.056
S
1.19
0.047
28-pin Standard Type One TSOP
Note: Controlling dimension: Millimeters
A
A
A
2
1
L
L
1
Y
c
E
H
D
D
b
e
Min.
Dimension in Inches
Nom. Max. Min. Nom. Max.
Symbol
1.20
0.05
0.15
1.05
1.00
0.95
0.17
0.10
11.70
7.90
13.20
0.50
0.00
0
0.20
0.27
0.15
0.21
11.80
11.90
8.00
8.10
13.40
13.60
0.55
0.60
0.70
0.25
0.10
3
5
0.047
0.006
0.041
0.040
0.035
0.007
0.008
0.011
0.004
0.006
0.008
0.461
0.465
0.469
0.311
0.315
0.319
0.520
0.528
0.536
0.022
0.020
0.024
0.028
0.010
0.000
0.004
0
3
5
0.002
A
A
b
c
D
E
e
L
L
Y
1
1
2
A
H
D
Dimension in mm
W24257A
Publication Release Date: May 1997
- 11 -
Revision A14
Headquarters
No. 4, Creation Rd. III,
Science-Based Industrial Park,
Hsinchu, Taiwan
TEL: 886-3-5770066
FAX: 886-3-5792647
http://www.winbond.com.tw/
Voice & Fax-on-demand: 886-2-7197006
Taipei Office
11F, No. 115, Sec. 3, Min-Sheng East Rd.,
Taipei, Taiwan
TEL: 886-2-7190505
FAX: 886-2-7197502
Winbond Electronics (H.K.) Ltd.
Rm. 803, World Trade Square, Tower II,
123 Hoi Bun Rd., Kwun Tong,
Kowloon, Hong Kong
TEL: 852-27513100
FAX: 852-27552064
Winbond Electronics North America Corp.
Winbond Memory Lab.
Winbond Microelectronics Corp.
Winbond Systems Lab.
2730 Orchard Parkway, San Jose,
CA 95134, U.S.A.
TEL: 1-408-9436666
FAX: 1-408-9436668
Note: All data and specifications are subject to change without notice.
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