Questions tagged [reliability]
The reliability tag has no usage guidance.
131
questions
18
votes
5answers
2k views
How can we test the lifespan of electrical components?
We work with some electronic devices in our projects. We are at the stage where we need to create some test strategy to validate the lifespan (e.g. 1 to 5 years) of our devices for which we provide ...
4
votes
4answers
121 views
Relay - Doesn't work…at first
I have a latching small signal <2A relay (V23079E1201B301) that switches between two audio signals. The relay has worked in about 10k boards over 7-8 years without much issue. We recently got a run ...
0
votes
0answers
36 views
Durability of SMD MEMS pressure sensors in pure oxygen enviroment
I have a question regarding durability/reliability of COTS SMD mems pressure sensors in oxygen rich (basically 100%) atmosphere under pressure of 1bar/1atm and temperature around 20C/293K.
Sensor ...
0
votes
0answers
39 views
Latching Priority Encoder, circuit works but I don't trust it
I added a schematic even though the question is actually too simple for it. The datasheets for the devices are likely to be more revealing.
The circuit is super simple. I have a 74HC148 priority ...
0
votes
0answers
36 views
How to detect brushless DC motor wear?
The manufacturer of the brushless motor does not specify a lifetime for the particular motor I am using (BLDC5-R-57BL120L2.) For my application it is essential that the axial and radial movement of ...
0
votes
1answer
51 views
Base-emitter reverse breakdown and current
I have a circuit as follows,
simulate this circuit – Schematic created using CircuitLab
which provides a control current to an OTA as \$i_\mathrm{abc} = (3.27\mathrm{V} - V_\mathrm{in})/R1\$. ...
0
votes
0answers
73 views
How does manufacturer determine initial tolerance for capacitors?
Short version: I understand resistor initial tolerance is commonly obtained through sorting process where manufacturer only picks resistor that has resistance within the advertised initial tolerance. ...
0
votes
1answer
68 views
Turn off MOSFET with diode - PWM controller Maximal output current
Here is my circuit (and I know that this circuit does not cause any problems at least for the moment):
For turning on, the maximal current from the pin "OUT" is limited by the resistance ...
0
votes
1answer
59 views
Is is possible to calculate the MTBF or Failure rate from a given datasheet when manufacturer have not given these details?
As there are new components getting added to the mouser or digikey, is it possible to calculate the failure rate based on some pre known facts and values? some vendors don't reply for weeks and I can'...
8
votes
1answer
503 views
What to check for when buying an electronic component or module?
This has been raised as a canonical Q and A for future reference
How can I acquire electronic parts/items/modules and ensure that there is minimal risk of them being unsuitable for my project or ...
0
votes
0answers
44 views
Why PBTI is recoverable, and NBTI is not recoverable?
Why we discuss more about NBTI in mosfet, not PBTI?
PBTI - postive bias temperature instability
NBTI - Negative Bias temperature instability
1
vote
1answer
96 views
Why do bare die chips (MOSFET) have a maximum storage temperature?
As far as I understand, a chip in general and a MOSFET in particular has a maximum operating temperature (let‘s say 125 °C or 150 °C for Si) because above that temperature the risk increases of ...
0
votes
2answers
46 views
Electronic device operating temperature declaration
How is device operating temperature range determined? I supposed that for a specified temperature range all the built in components have to support it. I am in doubt because I saw some commercial ...
1
vote
2answers
123 views
Why are 3.5mm audio jacks unreliable?
Several of my devices with 3.5mm jacks make unreliable connections. The sound will cut out when the plug is wiggled slightly, or one ear will not have sound at all, or the sound will "cancel" in a way ...
0
votes
4answers
194 views
Is exceeding Opamp Common Mode Voltage safe?
I understand that when you exceed an Opamps Common mode voltage limit that the output will no longer be reliable. And that this limit is often a bit less that the supply rails. But would slightly ...
0
votes
1answer
78 views
Li-Ion Battery Swelling Mechanism
I have recently had both a tablet (manufactured 2013) and a phone (manufactured 2017) battery
swell (both batteries are Li-ion). The photo below shows the tablet's damage. Both
batteries still ...
0
votes
1answer
37 views
Calculating FIT for Magnetic Sensors
We have qualified one of our magnetic sensors (80 samples, 1000 hours - JEDEC) with zero failures and we are asked to provide a FIT. The product is not repairable so I would think an MTTF would be ...
0
votes
1answer
624 views
MTBF / MTTF and parallel systems
I'm doing an MTBF calculation for a system. Basically I calculated or searched for the MTBFs / FITs of every component. Then added up the FITs and got the total MTBF.
My first question would be the ...
2
votes
0answers
53 views
Calculating reliability of a parallel redundant system
I'm trying to calculate the reliability of a system that has proven to be a bit more complicated than I thought. Here is the block diagram for the system:
Every single component in this diagram is a ...
2
votes
2answers
232 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 ...
26
votes
7answers
2k 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 ...
2
votes
0answers
42 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
votes
0answers
39 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
votes
1answer
65 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
votes
2answers
52 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
109 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
votes
0answers
420 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
vote
0answers
46 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
vote
0answers
231 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
vote
0answers
33 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
votes
1answer
86 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
votes
2answers
154 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
43 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
vote
4answers
702 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
133 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
98 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
5k 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
120 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
votes
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
89 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
votes
3answers
142 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
233 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
103 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
108 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
801 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
145 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
65 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
249 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
1k 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 ...
