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
- SEL Immune 110 MeV-cm
2
/mg
- SEU LET
TH
(0.25) = 52 cm
2
MeV
- Saturated Cross Section 2.8E-8 cm
2
/bit
-<1.1E-9 errors/bit-day, Adams 90% worst case
environment geosynchronous orbit
Packaging:
- 36-lead ceramic flatpack (3.831 grams)
Standard Microcircuit Drawing 5962-00536
- QML Q and V compliant part
INTRODUCTION
The UT9Q512E RadTolerant 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.
Writing to the device is accomplished by taking Chip Enable (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 (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 LOW and 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. UT9Q512E 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 UT9Q512E has three control inputs called Chip Enable (E),
Write Enable (W), and Output Enable (G); 19 address inputs,
A(18:0); and eight bidirectional data lines, DQ(7:0). E 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
1
0
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. UT9Q512E 20ns SRAM Pinout (36)
PIN NAMES
A(18:0)
DQ(7:0)
E
W
G
V
DD
V
SS
Address
Data Input/Output
Chip 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 Chip Enable, Output Enable, or valid address to
valid data output.
SRAM Read Cycle 1, the Address Access in figure 4a, 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 Chip
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 4b, 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 4c, 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
5a, 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
5b, is defined by a write terminated by 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. Radiation Hardness
Design Specifications
1
Total Dose
Heavy Ion
Error Rate
2
50
<1.1E-9
krad(Si)
Errors/Bit-Day
Notes:
1. The SRAM will not latchup during radiation exposure under recommended
operating conditions.
2. Adam’s 0% worst case 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 7.0V
-0.5 to 7.0V
-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
V
IN
PARAMETER
Positive supply voltage
Case temperature range
DC input voltage
LIMITS
4.5 to 5.5V
(C) screening: -55°C to +125°C
(W) screening: -40°C to +125°C
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
= 5.0V + 10%)
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
(TTL)
(TTL)
I
OL
= 8mA, V
DD
=4.5V (TTL)
I
OL
= 200μA,V
DD
=4.5V (CMOS)
I
OH
= -4mA,V
DD
=4.5V (TTL)
I
OH
= -200μA,V
DD
=4.5V (CMOS)
ƒ
= 1MHz @ 0V
ƒ
= 1MHz @ 0V
V
IN
= V
DD
and V
SS,
V
DD
= V
DD
(max)
V
O
= V
DD
and V
SS
V
DD
= V
DD
(max)
G = V
DD
(max)
V
DD
= V
DD
(max), V
O
= V
DD
V
DD
= V
DD
(max), V
O
= 0V
I
DD
(OP)
4
Supply current operating
@ 1MHz
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, -40°C, 25°C
125°C
50
mA
-2
-2
2.4
3.2
10
12
2
2
CONDITION
MIN
2
0.8
0.4
0.05
MAX
UNIT
V
V
V
V
V
V
pF
pF
μA
μA
I
OS2, 3
Short-circuit output current
-90
90
mA
I
DD
(OP)
4
Supply current operating
@50MHz
76
mA
I
DD
(SB)
Supply current standby
@0MHz
10
45
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.
[i=s]This post was last edited by L_954863658 on 2020-3-17 13:41[/i]I want to use a timer to set the timer to 1 millisecond. After passing the parameters according to the function definition, I can en...
Some netizens said they wanted to learn something about opencv. Then I will share two articles. [b]What is opencv[/b] OpenCV is an open source library for image processing, analysis, and machine visio...
I define a series of global variables in succession, for example, u8 temp1;u8 temp2;u8 temp3; Are their addresses continuous when the space is allocated? I think they should be continuous, but when I ...
In the past two days, I have been debugging the USART serial port program on the STM32 development board and encountered some problems: Using interrupts to send and receive data. When using USART1, da...
MSP430 LaunchPad is a new development board from TI. This development board not only has a USB programmer, but also has a USB to TTL serial port function, which is very convenient for debugging. It ca...
[URL=http://www.5s5f.net]http://www.5s5f.net[/URL] (foreign free English e-books, fashion magazines) [URL=http://www.bookgo.org ]http://www.bookgo.org [/URL](A large number of original English compute...
1. Several nouns
ABI:
The specifications that an executable file must follow in order to run in a specific execution environment;
Separately generated relocatabl...[Details]
There are many different ways of human-computer interaction. The more common ones are listed below:
Mouse interaction: Using a mouse to operate a computer and interact was the most common human...[Details]
A line scan lens is an industrial lens used with line scan cameras. Its imaging principle is to capture the image of the workpiece using a linear sensor and then perform digital signal processing t...[Details]
Whether it is an electric car or an ordinary fuel car, for the vast majority of car buyers, the final cost of use is what they care about most. For fuel cars, how to save fuel is what drivers care ...[Details]
Core point: The automotive industry chain and the humanoid robot industry have collaborative advantages in hardware, software, and scenarios. Upstream and downstream companies in the automotive ind...[Details]
Common Mode Semiconductor has officially released its latest generation of power management ICs—the GM6506 series. This fully integrated high-frequency synchronous rectification step-down p...[Details]
As the scale and business applications of national e-government networks continue to expand, the data and services transmitted over them are becoming increasingly sensitive and critical. To protect...[Details]
introduction
As “energy conservation and emission reduction” has become an indicator of the National Economic Development Outline of the 11th Five-Year Plan, people’s awareness of green enviro...[Details]
In the scorching summer, electric fans are a must-have for cooling down people's homes. However, I believe most people have encountered this situation: the fan is plugged in, the switch is pressed,...[Details]
Pure electric vehicles, structurally speaking, have components such as a power battery. In addition to the power battery, a small battery also powers some low-voltage electrical components and even...[Details]
With the rapid development of electric vehicles in my country, people are beginning to pay attention to the issue of radiation from electric vehicles. We all know that mobile phones emit radiation,...[Details]
With the advent of the electric car era, the number of pure electric vehicles has increased significantly, but many car owners do not know how to properly maintain pure electric vehicles. In additi...[Details]
Normally, we determine our location and where we want to go by comparing our surroundings with observation and simple GPS tools. However, this kind of reasoning is very difficult for self-driving c...[Details]
UPS stands for Uninterruptible Power Supply, which includes energy storage devices. It is mainly used to provide uninterruptible power supply for devices that require high power stability.
...[Details]
To improve the lateral active safety of intelligent connected vehicles, the identification and definition of unexpected functional safety scenarios for the EPS (Electronic Steering System) ...[Details]