inputs, A(14:0); and eight bidirectional data lines, DQ(7:0). E1
and E2 are device enable inputs that control device selection,
active, and standby modes. Asserting both E1 and E2 enables
the device, causes I
DD
to rise to its active value, and decodes the
15 address inputs to select one of 32,768 words in the memory.
W controls read and write operations. During a read cycle, G
must be asserted to enable the outputs.
Table 1. Device Operation Truth Table
G
W
X
X
0
1
1
E1
X
1
0
0
0
E2
3
0
X
1
1
1
I/O Mode
3-state
3-state
Data in
3-state
Data out
Mode
Standby
Standby
Write
Read
2
Read
Figure 2a. SRAM Pinout (36)
X
1
X
X
1
A14
A12
A7
A6
A5
A4
A3
A2
A1
A0
DQ0
DQ1
DQ2
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
V
DD
W
A13
A8
A9
A11
G
A10
E1
DQ7
DQ6
DQ5
DQ4
DQ3
0
Notes:
1. “X” is defined as a “don’t care” condition.
2. Device active; outputs disabled.
3. Tied active (i.e., logic 1) in the 28-pin DIP package.
READ CYCLE
A combination of W greater than V
IH
(min), E1 less than V
IL
(max), and E2 greater than V
IH
(min) defines a read cycle. Read
access time is measured from the latter of device enable, output
enable, or valid address to valid data output.
Read Cycle 1, the Address Access read in figure 3a, is initiated
by a change in address inputs while the chip is enabled with G
asserted and W deasserted. Valid data appears on data outputs
DQ(7:0) after the specified t
AVQV
is satisfied. Outputs remain
active throughout the entire cycle. As long as device enable and
output enable are active, the address inputs may change at a rate
equal to the minimum read cycle time (t
AVAV
).
Read Cycle 2, the Chip Enable-controlled Access in figure 3b,
is initiated by the latter of E1 and E2 going active while G
remains asserted, W remains deasserted, and the addresses
remain stable for the entire cycle. After the specified t
ETQV
is
satisfied, the eight-bit word addressed by A(14:0) is accessed
and appears at the data outputs DQ(7:0).
Read Cycle 3, the Output Enable-controlled Access in figure 3c,
is initiated by G going active while E1 and E2 are asserted, W
is deasserted, and the addresses are stable. Read access time is
t
GLQV
unless t
AVQV
or t
ETQV
have not been satisfied.
Figure 2b. SRAM Pinout (28)
PIN NAMES
A(14:0)
DQ(7:0)
E1
E2
1
Address
Data Input/Output
Enable 1
Enable 2
W
G
Write
Output Enable
V
DD
Power
V
SS
Ground
1. 36-lead flatpack only.
2
WRITE CYCLE
A combination of W less than V
IL
(max), E1 less than V
IL
(max),
and E2 greater than V
IH
(min) defines a write cycle. The state of
G is a “don’t care” for a write cycle. The outputs are placed in
the high-impedance state when either G is greater than
V
IH
(min), or when W is less than V
IL
(max).
Write Cycle 1, the Write Enable-controlled Access shown in
figure 4a, is defined by a write terminated by W going high, with
E1 and E2 still active. The write pulse width is defined by t
WLWH
when the write is initiated by W, and by t
ETWH
when the write
is initiated by the latter of E1 or E2. Unless the outputs have
been previously placed in the high-impedance state by G, the
user must wait t
WLQZ
before applying data to the eight
bidirectional pins DQ(7:0) to avoid bus contention.
Write Cycle 2, the Chip Enable-controlled Access shown in
figure 4b, is defined by a write terminated by the latter of E1 or
E2 going inactive. The write pulse width is defined by t
WLEF
when the write is initiated by W, and by t
ETEF
when the write
is initiated by the latter of E1 or E2 going active. For the W
initiated write, unless the outputs have been previously placed
in the high-impedance state by G, the user must wait t
WLQZ
before applying data to the eight bidirectional pins DQ(7:0) to
avoid bus contention.
RADIATION HARDNESS
The UT7156 SRAM incorporates special design and layout
features which allow operation in high-level radiation
environments.
Table 2. Radiation Hardness
Design Specifications
1
Total Dose
Error Rate
2
1.0E6
1.0E-10
rads(Si)
Errors/Bit-Day
Notes:
1. The SRAM will not latchup during radiation exposure under recommended
operating conditions.
2. 10% worst case particle environment, Geosynchronous orbit, 0.025 mils of
Aluminum.
3
ABSOLUTE MAXIMUM RATINGS
1
(Referenced to V
SS
)
SYMBOL
V
DD
V
I/O
T
STG
P
D
T
J
Θ
JC
I
I
PARAMETER
DC supply voltage
Voltage on any pin
Storage temperature
Maximum power dissipation
Maximum junction temperature
2
Thermal resistance, junction-to-case
3
DC input current
LIMITS
-0.5 to 7.0V
-0.5 to (V
DD
+ 0.3)V
-65 to +150°C
2.0W
+150°C
10°C/W
±
10 mA
Notes:
1. Stresses outside the listed absolute maximum ratings may cause permanent damage to the device. This is a stress rating only, functional operation of the device
and
at these or any other conditions beyond limits indicated in the operational sections of this specification is not recommended. E
xposure to absolute maximum rating
conditions for extended periods may affect device reliability.
2. Maximum junction temperature may be increased to +175C during burn-in and steady-static life.
°
3. Test per MIL-STD-883, Method 1012.
RECOMMENDED OPERATING CONDITIONS
SYMBOL
V
DD
T
C
V
IN
PARAMETER
Positive supply voltage
Case temperature range
DC input voltage
LIMITS
4.5 to 5.5V
-55 to +125°C
0V to V
DD
4
DC ELECTRICAL CHARACTERISTICS (Pre/Post-Radiation)*
(V
DD
= 5.0V±10%) (-55°C to +125°C)
SYMBOL
V
IH
V
IL
V
OL
V
OH
V
OH
C
IN1
C
IO1
I
IN
I
OZ
PARAMETER
High-level input voltage
Low-level input voltage
Low-level output voltage
High-level output voltage
High-level output voltage
Input capacitance
Bidirectional I/O capacitance
Input leakage current
Three-state output leakage current
(CMOS)
(CMOS)
I
OL
= 200µA, V
DD
= 4.5V (CMOS)
I
OH
= -200µA, V
DD
= 4.5V (CMOS)
I
OH
= -4mA, V
DD
= 4.5V (CMOS)
ƒ
= 1MHz @ 0V
ƒ
= 1MHz @ 0V
V
IN
= V
DD
and V
SS
V
O
= V
DD
and V
SS
V
DD
= 5.5V
G = 5.5V
I
OS2, 3
Short-circuit output current
V
DD
= 5.5V, V
O
= V
DD
V
DD
= 5.5V, V
O
= 0V
I
DD
(OP)
Supply current operating @1MHz
CMOS inputs (I
OUT
= 0)
V
DD
= 5.5V
I
DD1
(OP)
I
DD3
(SB)
4
Supply current operating
@ 25MHz
Supply current standby
@ 0Hz
CMOS inputs (I
OUT
= 0)
V
DD
= 5.5V
CMOS inputs (I
OUT
= 0)
E1 = V
DD
- 0.5, V
DD
= 5.5V
1.2
mA
120
mA
50
-90
+90
mA
mA
mA
-5
-10
V
DD
-0.05
4.2
4
7
5
10
CONDITION
MIN
3.5
1.5
0.05
MAX
UNIT
V
V
V
V
V
pF
pF
µA
µA
Notes:
* Post-radiation performance guaranteed at 25C per MIL-STD-883 Method 1019 at 5.0E rads(Si).
°
5
1. Measured only for initial qualification and after process or design changes that could affect input/output capacitance.
2. Supplied as a design limit but not guaranteed or tested.
3. Not more than one output may be shorted at a time for maximum duration of one second.
This paper discusses the design of a basic feedback oscillator, using a lumped element resonator with varactor control. A design center frequency of 1GHz has been chosen, with a tuning bandwidth of 50...
[color=black]This switching power supply is a low-power switching power supply. It inputs 220V AC mains power and outputs 12V DC power. The maximum output current is 1.3A. It is mainly used to power s...
My teacher and I are designing a piezoelectric ceramic drive power supply, which requires a DC 120V voltage. Previously, a senior student used five 220V--24V transformers, then rectified and stabilize...
I am a novice, and I need to use evc to develop an application to operate the registers of the network card (the network card is dm9000a wince platform). Can I call the driver function directly or use...
A friend gave me two tickets for Avatar that night, so my family of three rushed over. My husband took my daughter to watch the movie, and we waited outside. There were so many people, the movie theat...
The power consumption of the code is different when it is executed in different flash or SRAM, but after searching for a long time, I still can't find how to configure the code execution to different ...
According to foreign media reports, Ford Motor has applied to the U.S. Patent and Social Security Administration (USPTO) for a patent for a remote vehicle control system that may be used in future ...[Details]
On August 24th, Jin Yuzhi, CEO of Huawei's Intelligent Automotive Solutions BU, announced the first automotive application of Huawei Qiankun's unique Limera technology. This technology eliminates t...[Details]
A parallel inverter consists of two thyristors (T1 and T2), a capacitor, a center-tapped transformer, and an inductor. The thyristors provide a current path, while the inductor L maintains a consta...[Details]
In recent years, many people have switched to new energy vehicles, and this type of vehicle has indeed been highly sought after and is considered the future direction of automobile development, and...[Details]
The structure of an LCD TV primarily consists of the LCD display module, power module, driver module (primarily including the main driver board and tuner board), and keypad module. LCD display modu...[Details]
Smartphones have become essential digital devices, and the growing number of smartphone-centric applications is enriching people's lives. As users, they desire a better app experience and a wider r...[Details]
In the electronics manufacturing industry, surface mount technology (SMT) placement machines are core equipment for production lines. However, with many different models available on the market, ch...[Details]
There are many motors that can use thyristor speed control, and they can be used in almost all industries. Various types of motors, such as fans, pumps, AC motors, DC motors, torque motors, single-...[Details]
When American cartoonist Chester Gould sketched the watch on Dick Tracy's wrist, he had no idea that science fiction would become reality 70 years later. As a comic strip artist, Gould imagined fut...[Details]
According to Reuters, citing people familiar with the matter, British semiconductor design company Arm Holdings (NASDAQ:ARM) has hired Rami Sinno, head of Amazon's (NASDAQ:AMZN) artificial intellig...[Details]
With the development of vehicle technology, there are more types of cars. Cars are divided into hybrid, pure electric vehicles, and fuel vehicles. For hybrid cars, they are divided into plug-in hyb...[Details]
The automotive transmission is the foundation of a vehicle's motion. The vehicle's drivetrain transfers engine power to the drive wheels, enabling the vehicle to move. The vehicle's drivetrain cons...[Details]
Motor potting compound is a high-performance sealing material widely used for motor encapsulation and insulation. It is essential for motor protection and packaging. Its ideal moisture and water re...[Details]
introduction
Whether in the automotive entertainment or home theater system markets, consumers continue to demand more channels and speakers, each capable of handling higher audio po...[Details]
As AI accelerates across industries, the demand for data center infrastructure is also growing rapidly.
Keysight Technologies recently announced the release of "Beyond the Bottleneck...[Details]
Analog electronics
京公网安备 11010802033920号
EEWORLD
