M68AW031A
TABLE OF CONTENTS
SUMMARY DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Figure 2. Logic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Table 1. Signal Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Figure 3. SO Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Figure 4. TSOP Connections (Reverse) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Figure 5. TSOP Connections (Normal) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Figure 6. Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
MAXIMUM RATING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Table 2. Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
DC AND AC PARAMETERS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Table 3. Operating and AC Measurement Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Figure 7. AC Measurement I/O Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Figure 8. AC Measurement Load Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Table 4. Capacitance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Table 5. DC Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Table 6. Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Read Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Figure 9. Address Controlled, Read Mode AC Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Figure 10. Chip Enable or Output Enable Controlled, Read Mode AC Waveforms. . . . . . . . . . . . . . 9
Figure 11. Chip Enable Controlled, Standby Mode AC Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . 9
Table 7. Read and Standby Mode AC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Write Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 12. Write Enable Controlled, Write AC Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 13. Chip Enable Controlled, Write AC Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Table 8. Write Mode AC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 14. Low V
CC
Data Retention AC Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Table 9. Low V
CC
Data Retention Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
PACKAGE MECHANICAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
SO28 - 28 lead Plastic Small Outline, 300 mils body width, Package Outline . . . . . . . . . . . . . . . . 15
SO28 - 28 lead Plastic Small Outline, 300 mils body width, Package Mechanical Data . . . . . . . . . 15
TSOP28 - 28 lead Normal and Reverse Pinout Plastic Small Outline, Package Outline . . . . . . . . 16
TSOP28 - 28 lead Normal and Reverse Pinout Plastic Small Outline, Package Mechanical Data . 16
PART NUMBERING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Table 12. Ordering Information Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
REVISION HISTORY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Table 13. Document Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
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M68AW031A
SUMMARY DESCRIPTION
The M68AW031A is a 256 Kbit (262,144 bit)
CMOS SRAM, organized as 32,768 bytes by 8
bits. The device features fully static operation re-
quiring no external clocks or timing strobes, with
equal address access and cycle times. It requires
a single 2.7 to 3.6V supply. This device has an au-
tomatic power-down feature, reducing the power
consumption by over 99% when deselected.
The M68AW031A is available in SO28 (28-lead
Small Outline) and TSOP28 (28-lead Thin Small
Outline, Standard and Reverse Pinout) packages.
Figure 2. Logic Diagram
Table 1. Signal Names
A0-A14
Address Inputs
Data Input/Output
Chip Enable
Output Enable
Write Enable
Supply Voltage
Ground
VCC
DQ0-DQ7
E
15
A0-A14
W
M68AW031A
E
G
8
DQ0-DQ7
G
W
V
CC
V
SS
VSS
AI05935c
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M68AW031A
Figure 6. Block Diagram
A14
ROW
DECODER
A7
MEMORY
ARRAY
DQ7
I/O CIRCUITS
COLUMN
DECODER
DQ0
A0
E
W
A6
G
AI05919
MAXIMUM RATING
Stressing the device above the rating listed in the
Absolute Maximum Ratings table may cause per-
manent damage to the device. These are stress
ratings only and operation of the device at these or
any other conditions above those indicated in the
Operating sections of this specification is not im-
Table 2. Absolute Maximum Ratings
Symbol
I
O (1)
T
A
T
STG
V
CC
V
IO (2)
P
D
Output Current
Ambient Operating Temperature
Storage Temperature
Supply Voltage
Input or Output Voltage
Power Dissipation
Parameter
plied. Exposure to Absolute Maximum Rating con-
ditions for periods greater than 1 sec periods may
affect device reliability. Refer also to the STMicro-
electronics SURE Program and other relevant
quality documents.
Value
20
–55 to 125
–65 to 150
–0.5 to 4.6
–0.5 to V
CC
+0.5
1
Unit
mA
°C
°C
V
V
W
Note: 1. One output at time not to exceed 1 second duration.
2. Up to a maximum operating V
CC
of 3.6V only.
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