Questions tagged [tolerance]
A window of acceptance, often expressed as a percentage, in which a non-perfect value is still accepted as usable.
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Tolerance on a resistor when looking at a schematics
In the schematics at the end of this document, there are a bunch of resistors. The author says in a footnote:
Part Notes, All Pages:
Unless noted:
Resistors are 5%, 0.12 W, or better, for standard 5%...
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Is there a specific definition for the tolerance value of a resistor?
Is there any authoritative definition for what the tolerance value of a resistor actually specifies, or is it just a de-facto common understanding, or are the details left up to individual ...
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DC-DC Converter usual tolerance
I wonder what the usual voltage tolerance is for a low power (approx. 1-20 W) Buck converter (over its whole operating temperature range).
So far I have found values around +/- 1.5 %
What is your ...
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Pspice won't register assigned tolerances
I am trying to assign tolerances of a component using PSpice -> Advanced Analysis -> Assign Tolerances
I add PosTol and NegTol and a flat distribution. When I hit 'OK' or 'Apply', the window is ...
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Is there ever any reason to prefer 5% tolerance resistors over 1%?
I work at an electronics store and the other day a customer came in who was rebuilding a circuit board. I sold him some resistors, but later he came back in wanting to return some of them because they ...
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Calculation of tolerance of a resistor for voltage sensing
I want to calculate the tolerance of resistor accurately to run a simulation to simulate accuracy of voltage sensor. The resistor I am using is CRCW0603330RFKEA - 330 Ω from Vishay and I can't see ...
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Altium hole tolerance vs IPC hole tolerance
I would like to start using the hole tolerances in Altium to provide more information to my fab house.
What I'm trying to figure out is the interaction with the IPC fabrication allowances I have ...
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How can power factor be reliably estimated given the phase error in current sense transformers?
The majority of mains power sensing devices I've seen (both commercial products and ICs) utilise a current sensing transformer. Many of them also calculate or estimate power factor. However, the phase ...
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Cascading resistors in series
Suppose, let's assume an IC pin requires a 10kohm 1% tolerant resistor connected to ground for its proper operation.
In that case, can someone tell me whether I can split the required resistors into ...
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What is the maximum error of this ADC?
I've read every article on the first two pages of Google trying to understand DNL and INL. Not a single lesson gave a specific example I could relate to, so now I'm still wildly confused and have no ...
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What does it mean to have a settling time at 5% of final value?
I need to make my control system to have a tolerance of 5% in less than 0.5 seconds (settling time ts = 0.5s at 5%).
My question is: does 5% mean the error band can be between these values in red (...
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Measure capacitors in parallel and series to increase precision?
I measure a capacitor \$C_1\$ with an instrument that has a tolerance of measurement \$\pm 5\%.\$ I do the same with another cap \$C_2\$. Then I put \$C_1\$ and \$C_2\$ in parallel (values add up) and ...
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Component Tolerance Probability
This is more of a manufacturing question than anything else.
What is the probability distribution of component tolerances?
For example, let's say I ordered a 100 ohm, 5% resistor, and I order 100 ...
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Monte Carlo Analysis in LTspice: Gaussian or Uniform distribution for the tolerance of resistors?
I am running 1000 simulations in LTspice to do Monte Carlo Analysis of the output voltage signal on a circuit with 3% tolerance resistors.
Firstly, does LTspice assume the resistors' values are ...
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Root Sum Square (RSS) tolerance of parallel resistors
I am trying to figure out the formula for RSS-ing two parallel resistors, but for the life of me can't figure this out.
For series resistors it is easy, just $${R_1 + R_2} \pm \sqrt{ dR_1^2 + dR_2^2}$$...
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E Series: is there any place that explains it?
So I am doing a work on optimizing circuits, and I came to study the E series of components.
I'm a bit confused and I cannot understand soem things:
How do the tables of values (E3: 1.0, 2.2, 4.7) ...
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Root Sum Square
Can anyone in a simple way explain why this formula works. It is the Root Sum of Squares where you square your values then add together then take the square root. It seems to be used quite a lot in ...
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precise 50 Hz oscillator [closed]
I need an astable multi-vibrator at exactly 50 or 100 Hz with exactly 50% duty cycle.
using circuits like 555 can't give me that with the common well-known values of components R and C , let alone the ...
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Motor run capacitor tolerance
From wikipedia:
If a wrong capacitance value is installed, it will cause an uneven magnetic field around the rotor. This causes the rotor to hesitate at the uneven spots, resulting in irregular ...
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Any solution to reduce the tolerance of a potentiometer? [closed]
In my design we use a slider potentiometer value of 10k with tolerance of 20%.
At particular point of potentiometer whenever I come to that position my resistance value changes every time. Also every ...
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In terms of costs of mass production: is it better to try to reduce resistances' tolerance or capacitors' tolerance?
So I am doing a small project of optimization of components tolerance to reduce the impact of circuit sensitivity to meet a project specification.
Right now I am with 5% resistors and inductors and 3% ...
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How much is the tolerance of the transistors?
I am simulating circuits on SPICE (LTSpice and PSpice), I have assigned tolerances to both resistors, capacitors and inductors.
But now I would like to try to understand how much a transistor can ...
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Typical tolerance of transformer secondary voltage?
I bought a transformer that said it would transform 230VAC to 34VAC (actually 2x17VAC, but it came with instructions how to connect the two secondary windings in series to get 34VAC.)
Even taking into ...
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Can I use a .75 HP inverter drive in place of a .5 HP one?
I am trying to replace some .5 HP 3-phase AC 240V motor drives with a different brand. The new brand doesn't seem to offer a .5 HP variant. Would the .75 HP variant work?
Edit: A little twist -- the ...
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Capacitor Array Tolerance of Caps in Same Package
Consider an MLCC capacitor array like CA064X471J5GACTU. Its tolerance is 5% but does this apply to capacitors within the same package?
More specifically, I am wondering if the tolerance of caps within ...
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Voltage and current tolerances
I'm attempting to self-learn as much as I can about electrical fundamentals and circuit building (red flag here I'm sure, but want to be completely honest in the hopes that someone can offer some ...
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How can I calculate the worst-case Tj of a MOSFET in discontinuous operation at another Tamb?
I am faced with the task to calculate the maximum junction temperature of a MOSFET in a half-bridge, having conduction losses, switching losses and diode losses. The real difficulty comes from the ...
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Calculating resistor end-of-life drift in the worst case analysis
How is it possible to calculate the tolerance of the end-of-life based on this datasheet?
https://www.vishay.com/docs/53046/pfrr.pdf
My specs are -30°C to 60°C and I want to estimate the drift/ ...
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Selecting proper resistance based on tolerance
I want to replicate a project.
The specification lists several resistances.
But they only specify the value of the resistance.
I went to buy resistances, but they first had me select a tolerance.
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Is there a way to average resistors together to get a tighter overall resistance tolerance?
I have a very sensitive, kHz frequency level, application where I need two matched resistors of the same resistance better than 0.05%. Like maybe by one magnitude (0.005%).
I am basically needing to ...
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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. ...
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Ferrite bead DC-resistance tolerance
What is the DC-resistance tolerance for a smd ferrite bead (e.g. BLM18RK102SN1D)?
Does anyone know? The datasheets I have seen only give a maximum value for the DC-resistance.
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Is error due to sensor tolerance random or systematic? [closed]
Welcome all. It might sound like basic question however it is question worth asking.
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What's the precision of a quartz crystal?
Crystal datasheets usually list the following parameters:
The Frequency Tolerance of a crystal is defined as the allowable
deviation from the specified Frequency when measured at 25°C or room
...
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Placement of Through Hole with a High Tolerance Dimension
Beginner question here.
What does one do about the placement of the through hole when one dimension
of the part has a high tolerance.
For example, I place the through hole anticipating the center of ...
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Choosing resistors in series to make standard values
I am working on designing a precision analog filter for a university electronics project.
The resistance values I am using (to meet the filter specifications) are not E96 values, so I am combining ...
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What exactly does a resistor's tolerance rating mean?
I thought that I had this pretty much figured out over 30 years ago during my initial schooling, but various answers posted to a support forum of a major semiconductor manufacturer(name withheld to ...
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Why would a part be available as 4.99k and 5k?
I was looking at chip resistors, and came across the MORNTA1001AT5, which comes in many resistance values. The resistor tolerance is 0.1%, so what is the logic of having the part available in both 4....
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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 ...
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How to design two circuits with Instrumentation Amplifier to produce the same output?
I want to measure the current in a 5V circuit. The current is between 50uA and 2.5mA. The current is from a NTC and it changes slowly (10Hz measurement is fast enough).
Here is the typical ...
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Set the Gain of an Opamp Accurately Using a Potentiometer
I want to set the gain of an opamp accurately using an potentiometer, with low thermal drift and good long-term stability. From what I've read, there are three basic ways of doing it, but none of them ...
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Calculate the differential common-mode gain of instrumentation amplifier
I am trying to design an instrumentation amplifier with a CMRR of 50 dB.
I have to target a differential gain of 60 dB.
$$ CMRR(dB) = 50 dB = 20log(\frac{A_{vd1}}{A_{cm1}})+ 20log(\frac{A_{vd2}}{A_{...
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What's the DC voltage range typically tolerated by modern smartphones?
The modern USB charging circuitry of mobile phones is pretty sophisticated. For example they can negotiate higher charging voltages etc.
This question, inspired by a discussion on worldbuilding, is ...
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What is the impact of Earth's magnetic field polarity on consumer electronics?
Earth's magnetic poles are known to have inverted in the past. How are commonly used circuits or component of consumer electronics (from energy production/transportation to TVs, mobile phones and PCs) ...
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lm35 Temperature Readings are not right after sealing with Hot-melt adhesive (How mush has it Soldering max Temp toleration ?)
I need to seal the LM35 temp sensor so, I used this device for sealing it:
The code I have used are:
...
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Inductor size versus tolerance
Say I’m planning to prototype some circuits (filters, oscillators, etc.) by soldering the component leads together in a “hairball” construction. If I use typical 10% or 20% tolerance inductors, how ...
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Decreasing manufacturing variance in analogue designs
I'm designing some modular sensors for my company's internal testing. Most are analogue, with a sensor (PT100, current shunt, pressure transducer etc), some interfacing (REF200 based PT100 circuit for ...
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Question about the accuracy of integrated resistors
I'm studying the implementation of resistors in integrated technology. In particular the books deals with the accuracy of the obtained resistors. It says:
Then it says:
"We observe that the value of ...
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Does the LT Spice monte carlo simulation definitely output the max and min voltage for any number of simulation runs?
I have the following circuit, in which i need to calculate max and min voltages possible (considering resistor tolerance).
Does running a monte carlo simulation consider the absolute max and min ...
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Why so much variance in the continuity beeper threshold? How do these beepers work anyway?
In this answer it is mentioned that the EEVBlog-branded BM235 meter has a threshold of between 30 and 480 ohms for its continuity beeper (as seen on page 25 of the datasheet).
My first thought was "...