SRM2B256SLMX
55/70/10
256K-BIT STATIC RAM
q
q
q
q
Wide Temperature Range
Extremely Low Standby Current
Access Time 100ns (2.7V) 55ns (4.5V)
32,768 Words
×
8-Bit Asynchronous
s
DESCRIPTION
The SRM2B256SLMX is a low voltage operating 32,768 words
×
8-bit asynchronous, static, random
access memory fabricated using an advanced CMOS technology. Its very low standby power con-
sumption makes it ideal for applications requiring non-volatile storage with back-up batteries, and
–25 to 85
°
C operating temperature range makes it ideal for industrial use. The asynchronous and
static nature of the memory requires no external clock or refresh circuit. 3-state output ports allow easy
expansion of memory capacity. These features make the SRM2B256SLMX usable for a wide range
of applications, from microprocessor systems to terminal devices.
s
FEATURES
•
•
•
•
•
•
•
•
Wide temperature range . . . . . . . . . . . –25 to 85
°
C
Extended supply voltage range. . . . . . 2.7 to 5.5V
Fast access time . . . . . . . . . . . . . . . . . 100ns (3V
±
10%)
55ns (5V
±
10%)
Extremely low standby current . . . . . . SL Version
Completely static. . . . . . . . . . . . . . . . . No clock required
3-state output
Battery back-up operation
Package . . . . . . . . . . . . . . . . . . . . . . . SRM2B256SLCX . . . . . . . . . . . . . . . DIP2-28pin (plastic)
SRM2B256SLMX . . . . . . . . . . . . . . SOP2-28pin (plastic)
SRM2B256SLTMX . . . . . . . . . . . TSOP (I)-28pin (plastic)
SRM2B256SLRMX. . . . . . . . TSOP (I)-28pin-R1 (plastic)
000-97-MEM-1.0
S-MOS Systems, Inc. • 150 River Oaks Parkway • San Jose, CA 95134 • Tel: (408) 922-0200 • Fax: (408) 922-0238
57
SRM2B256SLMX55/70/10
s
PIN CONFIGURATION
(DIP/SOP2)
(TSOP)
OE
A11
A9
A8
A13
WE
V
DD
A14
A12
A7
A6
A5
A4
A3
22
23
24
25
26
27
28
1
2
3
4
5
6
7
21
20
19
18
17
16
15
14
13
12
11
10
9
8
A10
CS
I/O8
I/O7
I/O6
I/O5
I/O4
V
SS
I/O3
I/O2
I/O1
A0
A1
A2
A14
A12
A7
A6
A5
A4
A3
A2
A1
A0
I/O1
I/O2
I/O3
V
SS
(TSOP-R1)(Reverse bending)
A3
A4
A5
A6
A7
A12
A14
V
DD
WE
A13
A8
A9
A11
OE
7
6
5
4
3
2
1
28
27
26
25
24
23
22
8
9
10
11
12
13
14
15
16
17
18
19
20
21
A2
A1
A0
I/O1
I/O2
I/O3
V
SS
I/O4
I/O5
I/O6
I/O7
I/O8
CS
A10
SRM2B256SLTMX
s
PIN DESCRIPTION
A0 to A14
WE
OE
CS
I/O1 to I/O8
V
DD
V
SS
Address input
Write Enable
Output Enable
Chip Select
Data I/O
Power Supply (2.7V to 5.5V)
Power Supply (0V)
000-97-MEM-1.0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
SRM2B256SLRMX
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
SRM2B256SLMX/CX
S-MOS Systems, Inc. • 150 River Oaks Parkway • San Jose, CA 95134 • Tel: (408) 922-0200 • Fax: (408) 922-0238
59
SRM2B256SLMX55/70/10
s
ABSOLUTE MAXIMUM RATINGS
V
SS
= 0V
Parameter
Supply voltage
Input voltage
Input/output voltage
Power dissipation
Operating temperature
Storage temperature
Soldering temperature and time
Symbol
V
DD
V
I
V
I/O
P
D
T
OPR
T
STG
T
SOL
Rating
–0.5 to 7.0
–0.5* to 7.0
–0.5* to V
DD
+ 0.3
1.0
–25 to 85
–65 to 150
260
°
C, 10s (Lead only)
Unit
V
V
V
W
°
C
°
C
—
* V
I
, V
I/O
(Min.) = –3.0V when pulse width is less or equal to 50ns
s
DC RECOMMENDED OPERATING CONDITIONS
V
DD
= 3V
±
10%
Min.
V
DD
Supply voltage
V
SS
V
IH
Input voltage
V
IL
–0.3*
—
0.4
–0.3*
0
2.2
—
—
0
V
DD
+ 0.3
0
2.2
2.7
Typ.
—
Max.
3.3
Min.
4.5
V
SS
= 0V, T
a
= –25 to 85
°
C
V
DD
= 5V
±
10%
Typ.
—
—
—
—
Max.
5.5
0
V
DD
+ 0.3
0.8
V
V
V
V
Unit
Parameter
Symbol
* V
IL
(Min.) = –3V when pulse width is less or equal to 50ns
60
S-MOS Systems, Inc. • 150 River Oaks Parkway • San Jose, CA 95134 • Tel: (408) 922-0200 • Fax: (408) 922-0238
000-97-MEM-1.0
SRM2B256SLMX55/70/10
s
ELECTRICAL CHARACTERISTICS
q
DC Electrical Characteristics
V
DD
= 3V
±
10%
Min
Input leakage
Standby supply
current
I
LI
I
DDS
I
DDS1
I
DDA
Average operating
current
I
DDA
1
Operating supply
current
Output leakage
High level output
voltage
Low level output
voltage
I
DDO
I
LO
V
OH
V
OL
V
I
= 0 to V
DD
CS = V
IH
CS
≥
V
DD
– 0.2V
V
I
= V
IL
, V
IH
I
I/O
= 0mA, t
CYC
= Min
V
I
= V
IL
, V
IH
I
I/O
= 0mA, t
CYC
= 1
µ
s
V
I
= V
IL
, V
IH
I
LO
= 0mA
CS = V
IH
or WE = V
IL
or OE = V
IH
, V
I/O
= 0 to V
DD
I
OH
= –1.0mA, –0.5mA
*3
I
OL
= 2.1mA, 1.0mA
*3
–1
—
—
—
—
—
–1
2.4
—
Typ
*1
—
—
0.3
10
—
—
—
—
—
Max
1
2
25
15
5
5
1
—
0.4
(V
SS
= 0V, T
a
= –25 to 85
°
C)
Conditions
V
DD
= 5V
±
10%
Min
–1
—
—
—
—
—
–1
2.4
—
Typ
*2
—
—
0.5
30
—
—
—
—
—
Max
1
3.0
50
45
10
10
1
—
0.4
µ
A
mA
µ
A
mA
mA
mA
µ
A
V
V
Unit
Parameter
Symbol
*1 Typical values are measured at T
a
= 25
°
C and V
DD
= 3.0V
*2 Typical values are measured at T
a
= 25
°
C and V
DD
= 5.0V
*3 V
DD
= 3.0V
±
10%
q
Terminal Capacitance
Parameter
Address capacitance
Input capacitance
I/O capacitance
Symbol
C
ADD
C
I
C
I/O
Conditions
V
ADD
= 0V
V
I
= 0V
V
I/O
= 0V
Min
—
—
—
Typ
—
—
—
(f = 1MHz, T
a
= 25
°
C)
Max
8
8
10
Unit
pF
pF
pF
000-97-MEM-1.0
S-MOS Systems, Inc. • 150 River Oaks Parkway • San Jose, CA 95134 • Tel: (408) 922-0200 • Fax: (408) 922-0238
61