20ns (3.3 volt supply) maximum address access time
Asynchronous operation for compatibility with industry-
standard 512K x 8 SRAMs
TTL compatible inputs and output levels, three-state
bidirectional data bus
Typical radiation performance
- Total dose: 50krads
- >100krads(Si), for any orbit, using Aeroflex UTMC
patented shielded package
- SEL Immune >80 MeV-cm
2
/mg
- LET
TH
(0.25) = >10 MeV-cm
2
/mg
- Saturated Cross Section cm
2
per bit, 5.0E-9
- <1E-8 errors/bit-day, Adams 90% geosynchronous
heavy ion
Packaging options:
- 36-lead ceramic flatpack (3.42 grams)
- 36-lead flatpack shielded (10.77 grams)
Standard Microcircuit Drawing 5962-99607
- QML T and Q compliant
INTRODUCTION
The QCOTS
TM
UT8Q512 Quantified Commercial Off-the-
Shelf product is a high-performance CMOS static RAM
organized as 524,288 words by 8 bits. Easy memory expansion
is provided by an active LOW Chip Enable (E), an active LOW
Output Enable (G), and three-state drivers. This device has a
power-down feature that reduces power consumption by more
than 90% when deselected
.
Writing to the device is accomplished by taking Chip Enable
one (E) input LOW and Write Enable (W) inputs LOW. Data on
the eight I/O pins (DQ
0
through DQ
7
) is then written into the
location specified on the address pins (A
0
through A
18
). Reading
from the device is accomplished by taking Chip Enable one (E)
and Output Enable (G) LOW while forcing Write Enable (W)
HIGH. Under these conditions, the contents of the memory
location specified by the address pins will appear on the I/O pins.
The eight input/output pins (DQ
0
through DQ
7
) are placed in a
high impedance state when the device is deselected (E, HIGH),
the outputs are disabled (G HIGH), or during a write operation
(E LOWand W LOW).
Clk. Gen.
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
Pre-Charge Circuit
Row Select
Memory Array
1024 Rows
512x8 Columns
I/O Circuit
Column Select
Data
Control
CLK
Gen.
A10
A11
A12
A13
A14
A15
A16
A17
A18
DQ
0
- DQ
7
E
W
G
Figure 1. UT8Q512 SRAM Block Diagram
1
DEVICE OPERATION
A0
A1
A2
A3
A4
E
DQ0
DQ1
V
DD
V
SS
DQ2
DQ3
W
A5
A6
A7
A8
A9
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
NC
A18
A17
A16
A15
G
DQ7
DQ6
V
SS
V
DD
DQ5
DQ4
A14
A13
A12
A11
A10
NC
The UT8Q512 has three control inputs called Enable 1 (E), Write
Enable (W), and Output Enable (G); 19 address inputs, A(18:0);
and eight bidirectional data lines, DQ(7:0). E Device Enable
controls device selection, active, and standby modes. Asserting
E enables the device, causes I
DD
to rise to its active value, and
decodes the 19 address inputs to select one of 524,288 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
X
1
X
W
X
0
1
1
E
1
0
0
0
I/O Mode
3-state
Data in
3-state
Data out
Mode
Standby
Write
Read
2
Read
Figure 2. 25ns SRAM Pinout (36)
1
0
PIN NAMES
A(18:0)
DQ(7:0)
E
W
G
V
DD
V
SS
Address
Data Input/Output
Enable
Write Enable
Output Enable
Power
Ground
Notes:
1. “X” is defined as a “don’t care” condition.
2. Device active; outputs disabled.
READ CYCLE
A combination of W greater than V
IH
(min) and E less than V
IL
(max) defines a read cycle. Read access time is measured from
the latter of Device Enable, Output Enable, or valid address to
valid data output.
SRAM Read Cycle 1, the Address Access 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
).
SRAM read Cycle 2, the Chip Enable - Controlled Access in
figure 3b, is initiated by E 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(18:0) is accessed and appears at the data
outputs DQ(7:0).
SRAM read Cycle 3, the Output Enable - Controlled Access in
figure 3c, is initiated by G going active while E is 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.
2
WRITE CYCLE
A combination of W less than V
IL
(max) and E less than
V
IL
(max) 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 in figure
4a, is defined by a write terminated by W going high, with E
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 E. 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 nine bidirectional pins DQ(7:0) to avoid bus
contention.
Write Cycle 2, the Chip Enable - Controlled Access in figure
4b, is defined by a write terminated by the latter of E 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 E 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.
TYPICAL RADIATION HARDNESS
Table 2. Typical Radiation Hardness
Design Specifications
1
Total Dose
Heavy Ion
Error Rate
2
50
<1E-8
krad(Si) nominal
Errors/Bit-Day
Notes:
1. The SRAM will not latchup during radiation exposure under recommended
operating conditions.
2. 90% worst case particle environment, Geosynchronous orbit, 100 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 4.6V
-0.5 to 4.6V
-65 to +150°C
1.0W
+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, and functional operation of the device
at these or any other conditions beyond limits indicated in the operational sections of this specification is not recommended. Exposure to absolute maximum rating
conditions for extended periods may affect device reliability and performance.
2. Maximum junction temperature may be increased to +175°C during burn-in and steady-static life.
3. Test per MIL-STD-883, Method 1012.
RECOMMENDED OPERATING CONDITIONS
SYMBOL
V
DD
T
C
PARAMETER
Positive supply voltage
Case temperature range
LIMITS
3.0 to 3.6V
(C) screening: -55° to +125°C
(E) screening: -40° to +125°C
V
IN
DC input voltage
0V to V
DD
4
DC ELECTRICAL CHARACTERISTICS (Pre/Post-Radiation)*
(-55°C to +125°C for (C) screening and -40
o
C to +125
o
C for (W) screening) (V
DD
= 3.3V + 0.3)
SYMBOL
V
IH
V
IL
V
OL1
V
OL2
V
OH1
V
OH2
C
IN1
C
IO1
I
IN
I
OZ
PARAMETER
High-level input voltage
Low-level input voltage
Low-level output 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
= 8mA, V
DD
=3.0V
I
OL
= 200µA,V
DD
=3.0V
I
OH
= -4mA,V
DD
=3.0V
I
OH
= -200µA,V
DD
=3.0V
ƒ
= 1MHz @ 0V
ƒ
= 1MHz @ 0V
V
SS
< V
IN
< V
DD,
V
DD
= V
DD
(max)
0V < V
O
< V
DD
V
DD
= V
DD
(max)
G = V
DD
(max)
0V < V
O
< V
DD
Inputs: V
IL
= 0.8V,
V
IH
= 2.0V
I
OUT
= 0mA
V
DD
= V
DD
(max)
Inputs: V
IL
= 0.8V,
V
IH
= 2.0V
I
OUT
= 0mA
V
DD
= V
DD
(max)
Inputs: V
IL
= V
SS
I
OUT
= 0mA
E = V
DD
- 0.5
V
DD
= V
DD
(max)
V
IH
= V
DD
- 0.5V
-55°C and 25°C
-40
o
C and 25
o
C
+125°C
-2
-2
2.4
V
DD
-0.10
10
12
2
2
CONDITION
MIN
2.0
0.8
0.4
0.08
MAX
UNIT
V
V
V
V
V
V
pF
pF
µA
µA
I
OS2, 3
I
DD
(OP)
Short-circuit output current
Supply current operating
@ 1MHz
-90
90
125
mA
mA
I
DD1
(OP)
Supply current operating
@40MHz
180
mA
I
DD2
(SB)
Nominal standby supply current
@0MHz
6
6
15
mA
mA
mA
Notes:
* Post-radiation performance guaranteed at 25°C per MIL-STD-883 Method 1019.
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.
[size=5]OC502X series LED constant current driver chip[/size][size=4][b]South China general agent Xinhai Innovation Technology Co., Ltd. supplies high-quality OC5022/OC5028/OC5021/[/b][b]OC5021/[/b][b...
Step 1: Configure GPIO port
GPIO_setConfig(uint_least8_t index,GPIO_PinConfig pinConfig);//index: IO port to be configured//pinConfig: Set the mode of the IO port, different parameters can use the "|"...
[:)] Can anyone provide some tips on selecting optical isolators and the differences between various models? ! ! ! For example: Performance comparison between TLP521-4 and PC817...
Link's cmd file is used to locate the DSP code. Since the compilation result of the DSP compiler is not located, the DSP has no operating system to locate the execution code, and the configuration of ...
In recent years, with the increasing demand for manufacturing and automated production management, industrial barcode scanners have gradually become an indispensable part of the industrial manufact...[Details]
Some time ago, I attended the 4th Energy Chemistry Forum of the Chinese Chemical Society and learned about high-energy-density and high-safety batteries. I would like to summarize and share this wi...[Details]
On August 22, Lantu Motors officially launched its Lanhai Intelligent Hybrid technology via an online livestream. This intelligent hybrid technology, which integrates a full-range 800V high-voltage...[Details]
Recently, South Korean robotics giant WIRobotics launched its first general-purpose humanoid robot, ALLEX, at the Robotics Innovation Center (RIH) at the Korea University of Science and Technology....[Details]
1 Source of creativity
With the further development of electronic technology, electronic pets have gradually entered people's family life. At present, there are two main categories of relative...[Details]
With the development of science, the use of variable frequency technology is becoming more and more widespread, and it is used in both industrial equipment and household appliances. Inverter air co...[Details]
For today's new energy vehicles, they have different configurations from fuel vehicles, and some configurations have also become a selling point for manufacturers. Compared with traditional vehicle...[Details]
On August 21, it was reported that Intel's new generation of AI chip Jaguar Shores was recently exposed for the first time.
According to photos shared by Andreas Schilling, the Jaguar Shores t...[Details]
Definitions of VR
, AR, and MR:
What is Virtual Reality?
Virtual Reality (VR), also known as "spiritual realm" or "illusion," is a high-tech technology that has emerged in recent ye...[Details]
Lithium-ion batteries are a key component of electric vehicles. Their high energy density enables them to store a large amount of energy in a relatively compact and lightweight package, which is cr...[Details]
Using an electronic load is like thinking of it as a resistor that dissipates the power supply's output. The most straightforward mode is the CR constant resistance mode. In this mode, by setting a...[Details]
In industrial production, many different controllers are often used, such as those for pressure, flow, electrical parameters, temperature, and sound. However, due to the limitations of the on-site ...[Details]
ESD protection diodes are specialized for small-signal ESD protection or surge protection TVS arrays, often used for multi-circuit protection. Their small package size, low on-state voltage, high i...[Details]
Deep in the laboratory, a seemingly ordinary piece
of
battery
material
was fed into the China Advanced Research Reactor (CARR). Scientists activated the neutron depth profiling device,...[Details]
Servo motors, also known as actuator motors, serve as actuators in automatic control systems, converting received electrical signals into angular displacement or angular velocity output on the moto...[Details]
LED Zone
京公网安备 11010802033920号
EEWORLD
