Questions tagged [reliability]
The reliability tag has no usage guidance.
113
questions
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2answers
126 views
Can an electronic system be built with absolutely no single point of failure?
Is it possible to make an electronic system, where every sub-system is duplicated and absolutely nothing is a single point of failure and if a failure (or multiple failures) occurs the system itself ...
23
votes
6answers
1k views
How to design electronics to last 40 years or more?
I've been reading about the Voyager space probes and am very curious about how you design electronics and instrumentation for a very long life (40+ years) without any physical maintenance.
My guesses ...
1
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0answers
31 views
Can reverse breakdown voltage be used to simulate lifetime aging of phototransistors?
As phototransistors age, their responsivity to light decreases (a fixed amount of light generate less photocurrent). To simulate long-term aging of phototransistors in a short period of time, one can ...
0
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0answers
36 views
Junction Temperature Estimation Error
When predicting the junction temperature (Tj) of semiconductor chips (for example IGBTs) by available thermal models such as FEM simulations, how much is the maximum permissible Tj estimation error ...
0
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1answer
59 views
When to use a terminal pin?
Would you ever be advised to solder hookup wire to a terminal pin (and maybe sleeve it with heat shrink) instead of soldering it directly to the PCB?
0
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2answers
49 views
12V Car headlight halogens vs. 240V mains golf balls (longevity)
The halogen headlights on my car must be about ten years old; I've never changed them and they put up with vibration, extremes of temperature etc.
Yet the 40W mains ones in my house (normally dimmed) ...
0
votes
1answer
40 views
MOSFET and TVS Voltage requirements for 120V single phase AC circuit
I am designing a circuit that will gate single phase 120V AC through back-to-back N-channel MOSFETs connected as shown below. When passing AC, one MOSFET is on and the body diode in the other is ...
0
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0answers
113 views
Deciding between ULN2804 or ULN2803 with 74HC595
I'm making a circuit with Arduino + 74HC595 + (ULN2804 / ULN2803) to drive a few 12 V Motors.
I'm trying to decide whether to use the ULN2804 or ULN2804. On testing, performance of both is fine, ...
1
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0answers
41 views
Majority Voter for complex data
How is a majority voter for complex data implemented?
If there is only one integer value which should be compared you can use a discrete circuit but how does it work for multiple datasets and floating ...
1
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0answers
78 views
Estimating gate or transistor count for an IC
I'm messing around with calculating predicted failure rates using MIL-HDBK-217F. For microcircuits (depending on linear or digital) you need to come up with a gate count or a transistor count for the ...
1
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0answers
30 views
Standard LiPo battery packs & product liability
I'm designing a high-power portable product that I would like to eventually bring to market. I need to use LiPo battery packs in order to achieve sufficient energy density, but I do not think I will ...
0
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0answers
53 views
How to estimate brushed motor usage (age) from carbon brushes corrosion
Is there a model to estimating the total number of turns a brushed motors has made during its life if we know that the carbon brushes have corroded by x mm or mm^3?
0
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1answer
48 views
Stagger Traces in a Flex Circuit?
I am designing a connector to PCB interface using a flex-circuit. Stackup is R-F775 2-layers with plated thru-holes and stiffeners (though the area in question has only traces). I'm wondering if it ...
0
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2answers
105 views
STM32F405 Setting Clock Freq Less than Max 168 MHz
For STM32F405 the max system clock frequency is 168 MHz. I want to run it at marginally lower frequency only for the sake of safety and reliability because my application will run non-stop through out ...
0
votes
1answer
47 views
Determining Absolute Maximums for IC Output Current and Power
I'm having a small gap in understanding with a project I'm working on. The project is reliability related and requires looking at the absolute maximum values for some 54ALS family logic (Max Vcc, ...
1
vote
0answers
42 views
Thermal Faliure of thermal overload protected ICs
I have encountered a number of instances now where ICs that supposedly include "thermal overload protection" will still heat up until they fry. Examples: LM338,LM2576.
These devices datasheets ...
1
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4answers
478 views
Is an ethernet switch considered as an ASIC?
I work as an electronic reliability engineer. In order to estimate the
reliability of integrated circuits, I need to know their type. Thus my question.
Is this ethernet switch Marvell Link Street-...
1
vote
4answers
122 views
Are circuits damaged by a constant 55°C environment?
I know that sun like temperatures kill electronics, but what about 55°C if it's constant?
I have a small commercial web camera that is officially rated 0°C to 70°C. It has no jelly capacitors. I ...
2
votes
1answer
43 views
Failure Rate calculation based on manufacturing defects (capacitor)
Electronics failure rates typically follow the exponential distribution and models like Prism, Mil-Hdbk-217 or 217Plus (newer) are used to predict failure rates.
We are currently in the production ...
6
votes
4answers
3k views
Measuring AC voltage without a transformer using a microcontroller
As I have no practice with AC voltages, I'm asking if the following circuit is reliable for measuring AC voltages about 110Vca and 220Vca 50Hz/60Hz.
I have already made it with a small transformer. ...
3
votes
0answers
112 views
Could a pic32 run for thousands of years? [closed]
By estimates based on known parameters of IC aging, could a standard pic32, if it is kept running in a vacuum or inert gas filled chamber, run for thousands of years or would effects like electro ...
0
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0answers
75 views
Waterproof PCB pump driving stage
We are having issues with a small 12V DC pump which is used in a number of test systems in the field. The pump is powered by a standard DC power supply and integrates a small PCB driving stage, with ...
1
vote
0answers
87 views
Failures on underside layers of a chip in IGBT power modules
Does somebody know how I can detect a layer of IGBT modules in which a thermal failure, e.g., voids, cracks, delaminations of solder joints, has taken place?
We know there is fatigue in both solder ...
0
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3answers
132 views
Can you approximately detect the closure of up to 100,000 switches using a resistor chain?
Consider the following outline circuit:-
It is a series of switch controllers that can short out parts of a chain of serially connected resistors. The short is accomplished with a BJT or MOSFET. A ...
2
votes
2answers
214 views
Reliability of electronic components in space [closed]
The Tesla car being recently shot into space made me wonder about the reliability of common electronic components in hard vacuum. I'm asking about the kind of components you would find in Musks's car-...
2
votes
1answer
86 views
What is maximum ESD current flowing through the pin for HBM model?
I have a given specification HBM ESD tolerance on my IC (For instance 1kV). I just want to estimate the maximum current which will flow on the pin in question and so determinate the clamp point on the ...
3
votes
2answers
105 views
Detecting on- and off-state of a micro switch
For safety reasons I need to make sure that I am still detecting the correct state of a micro switch and not for example a loss of power, broken cable, etc.
What are cheap and reliable ways of doing ...
1
vote
1answer
547 views
What components have a MSL of 5 and 6?
Moisture Sensitivity Level (MSL) relates to the packaging and handling precautions for some semiconductors.
Components with an MSL of 1 have an unlimited floor life, whereas components with an MSL of ...
6
votes
1answer
121 views
Test fixture PCB reliability metrics?
I am working on a project for a client that involves developing a reliability test fixture that will be used for stressing the end test device (DUT). The test fixture is a PCB which has linear power ...
1
vote
1answer
63 views
unique lead acid application question
Can anyone tell me what the non-cycling lifetime of a lead acid cell(s) is, under some kind of float or trickle charge?
Specifically, I need:
300W for 2 seconds
either at +24V with no conversion, ...
0
votes
0answers
195 views
Connect unused inputs/outputs on RS232 line driver/receiver Chip
What is the safest (and reliable) way to deal with unused input/output pins of serial comm. chips like MAX232, ST3232, etc..
So far i'm familiar with these three options:
Input and Output Not ...
5
votes
1answer
888 views
Mosfet failure in DC-DC switching converter: root cause analysis and countermeasures
I'm dealing with a pilot project which involves several units on the field (around 15 units) powered by a control card which needs to drive two resistive loads in DC in the range of 13-5 VDC. Each of ...
3
votes
2answers
299 views
Reliability and MTBF
For an electronic device the the MTBF requirement is 4500 hours per year for 10 years, what does this MTBF mean and how to convert it into hours?
0
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1answer
94 views
Quality parameters to include in contract with hardware supplier [closed]
my company (not related to electronics at all) is now getting a simple control board for a product designed by a third party. The very same third party will also be in charge of building such control ...
1
vote
1answer
823 views
Driving relay with PC serial port fails after few hours
Ive been trying to use this schematic:
to drive relay (from this answer).
(Components are as specified in schematics, with D2 being 1N4007)
...
2
votes
2answers
216 views
How to roughly know if a electronic scheme will fail soon and protect from it?
I am thinking of a farming project that includes using some board like Arduino, Raspberry Pi or Onion Mega (the list is not exclusive).
As the system will work with sensors and support life of its ...
2
votes
2answers
750 views
Board to Board Connections in Potted Electronics
We are contemplating a design which will need 2 PCBAs and be potted. One board is quite "special" so it's rather impractical to reduce the design to a single PCBA.
The conventional wisdom is that ...
4
votes
1answer
3k views
How to calculate aging tolerance of Resistor?
I wanted to calculate the worst case minimum and maximum value of Resistor 1K by considering all the
tolerances(initial tolerance,temperature,environmental factors and aging).
Here is the link for ...
1
vote
6answers
557 views
MOSFET reliability for critical applications
I am working on a critical circuit that drives a DC motor in an aircraft landing gear system. The electric motor is a simple DC motor where one polarity extends the landing gear and reversing the ...
3
votes
1answer
308 views
Thermal Stability of Electrolytic Capacitors
Aluminium Electrolytic Caps do dissipate power .This can be significant when the ripple current is large leading to Ohmic heating due to the ESR .Reputable manufacturers do provide Ripple current ...
0
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2answers
225 views
24AWG vs 26AWG for mechanic reliability
I have to choose a cable that will be bent and may be "stretch" a bit by our users. Which gauge would you advice between 24AWG and 26AWG to resist better ?
I guess it is better also to have more ...
1
vote
1answer
203 views
Any reliability concern if I don't add UVLO protection circuit?
I am designing a lithium-ion battery operated device. My concern is when the battery voltage drains to near min. operating voltage (3.3V) of the system, the system starts to reboot and struggles to ...
0
votes
1answer
488 views
Trimpot potentiometer rotational life Vs load life
I'm dealing with an application which makes use of an adjustable linear voltage regulator (LT3080). A trimpot potentiometer is used in place of the set resistance Rset to regulate the output voltage. ...
2
votes
1answer
282 views
Pluggable terminal connector long term reliability
I'm investigating the issues related to long term reliability of pluggable terminals of "Phoenix" style. This terminals are available in a range of pitch and configurations (right angle, straight...). ...
4
votes
2answers
1k views
Refreshing flash memories. Does it work?
We all know that the flash memories have data retention time of around 10..20 years.
But what if we need to design a device that has to work for 1000 years?
The obvious solution is to make a flash ...
-1
votes
1answer
162 views
Does merging the chip and the contact pad in a chip-and-pin card make the whole module less reliable?
This picture is from here (A and B letters are irrelevant for this question). A chip-and-pin card like Visa Electron has a ...
-3
votes
4answers
324 views
How to design schematic with infinite life expectancy [closed]
Well I know there is nothing infinite and every device can break on some circumstances.
But still, how to design electronic devices that to be able to function continuously for very long time.
Lets ...
1
vote
1answer
62 views
Is there an electronic pre-treatment spray for long life reliability in connectors?
Is there a good spray or paint-on treatment that I can apply to small electronic connectors before connecting them, that will help them maintain a good connection over long spans of time?
I am ...
4
votes
1answer
279 views
Does the separation of the differential pair shielding of a SATA cable matter?
Basically I want to replace a consumer grade SATA cable with something a bit more tolerant to high temps and other environmental stresses.
The general cross section of a SATA cable looks like this:
...
1
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2answers
990 views
What is the expected lifespan of those 16x2 character LCD?
I want to use the HD44780 character LCD (commonly available in 16x2 characters, though I am using the 20x4 version) in an industrial application but since it will be on 24x7, I am just a bit worried ...
