The AS7C4098 and AS7C34098 are high-performance CMOS 4,194,304-bit Static Random Access Memory (SRAM) devices
organized as 262,144 words × 16 bits. They are designed for memory applications where fast data access, low power, and
simple interfacing are desired.
Equal address access and cycle times (t
AA
, t
RC
, t
WC
) of 10/12/15/20 ns with output enable access times (t
OE
) of 5/6/7/8 ns are
ideal for high-performance applications. The chip enable input CE permits easy memory expansion with multiple-bank
memory systems.
When CE is High the device enters standby mode. The standard AS7C4098/AS7C34098 is guaranteed not to exceed 110/
72mW power consumption in CMOS standby mode. A write cycle is accomplished by asserting write enable (WE) and chip
enable (CE). Data on the input pins I/O1–I/O16 is written on the rising edge of WE (write cycle 1) or CE (write cycle 2). To
avoid bus contention, external devices should drive I/O pins only after outputs have been disabled with output enable (OE) or
write enable (WE).
A read cycle is accomplished by asserting output enable (OE) and chip enable (CE), with write enable (WE) High. The chip
drives I/O pins with the data word referenced by the input address. When either chip enable or output enable is inactive, or
write enable is active, output drivers stay in high-impedance mode.
These devices provide multiple center power and ground pins, and separate byte enable controls, allowing individual bytes to
be written and read. LB controls the lower bits, I/O1–I/O8, and UB controls the higher bits, I/O9–I/O16.
All chip inputs and outputs are TTL- and CMOS-compatible, and operation is from either a single 5V (AS7C4098) or 3.3V
(AS7C34098) supply. Both devices are available in the JEDEC standard 400-mL, 44-pin SOJ and TSOP 2 packages.
Absolute maximum ratings
Parameter
Voltage on V
CC
relative to GND
Voltage on any pin relative to GND
Power dissipation
Storage temperature
Ambient temperature with V
CC
applied
DC current into outputs (low)
Device
AS7C4098
AS7C34098
Symbol
V
t1
V
t1
V
t2
P
D
T
stg
T
bias
I
OUT
Min
–0.50
–0.50
–0.50
–
–65
–55
–
Max
+7.0
+5.0
V
CC
+0.50
1.5
+150
+125
±20
Unit
V
V
V
W
°C
°C
mA
Note: Stresses greater than those listed under
Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress rating only and
functional operation of the device at these or any other conditions outside those indicated in the operational sections of this specification is not implied.
Exposure to absolute maximum rating conditions for extended periods may affect reliability.
Truth table
CE
H
L
L
L
WE
X
H
X
H
OE
X
H
X
L
LB
X
X
H
L
H
L
L
UB
X
X
H
H
L
L
H
L
L
I/O1–I/O8
High Z
High Z
D
OUT
High Z
D
OUT
D
IN
High Z
D
IN
I/O9–I/O16
High Z
High Z
High Z
D
OUT
D
OUT
High Z
D
IN
D
IN
Mode
Standby (I
SB
, I
SB1
)
Output disable (I
CC
)
Read (I
CC
)
L
L
X
H
L
Write (I
CC
)
Key: X = Don’t care, L = Low, H = High.
1/13/05;
v.1.9
Alliance Semiconductor
P. 2 of 10
AS7C4098
AS7C34098
®
Recommended operating conditions
Parameter
AS7C4098
Supply voltage
AS7C34098
AS7C34098
AS7C4098
Input voltage
commercial
industrial
AS7C34098
Symbol
V
CC
(12/15/20)
V
CC
(10)
V
CC
(12/15/20)
V
IH
V
IH
V
IL1
Ambient operating temperature
T
A
T
A
Min Typical
4.5
3.15
3.0
2.2
2.0
–0.5
0
–40
5.0
3.3
3.3
–
–
–
–
–
Max
5.5
3.6
3.6
V
CC
+ 0.5
V
CC
+ 0.5
0.8
70
85
Unit
V
V
V
V
V
V
°C
°C
1 V
IL
min = –1.0V for pulse width less than 5ns.
DC operating characteristics (over the operating range)
