Questions tagged [accuracy]
The accuracy tag has no usage guidance.
142 questions
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Precise Electronic Measurements
I've been looking into various electronic components and noticed rampant 5%, 10%, and even 20% tolerances and accuracies not only in basic components such as capacitors, inductors, and resistors, but ...
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"50 Ohm" vs "50 Ohm terminated" in ACV accuracy specs
In the accuracy specifications for an AC voltage measurement with a Keysight 3458A, there is a distinction between source impedance of "50 Ohm" and "50 Ohm terminated" for the &...
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What is the best and simplest way to generate multiple accurate reference voltages?
I need several reference DC voltages to use them to calibrate hundreds of circuit boards manufactured in our facility.
The voltages to be calibrated are
5V
10V
100V
200V
500V
The accuracy required ...
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2
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Multimeter Range and Resolution
I'm confused as to how my multimeter takes readings, especially since its not an auto-range multimeter. I have to switch to the desired range to carry out measurements. Unfortunately, the resolution ...
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Easiest way to get highly-accurate frequency reference?
I just want to check the calibration of my frequency counter, so anything constant under 250 MHz would work(?)
Mains are synced to atomic clocks, to maintain wall clock accuracy, but only ...
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Understanding accuracy specification for an electronic load box
I am using a BK Precision 8600 electronic load box. I am using it in constant resistance mode (CR mode). I have two resistances I am using, 15Ω and 5Ω, and I am interested in determining the max/min ...
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Shunt's thermal EMF (Seebeck effect) vs Kelvin connection?
While reading this Vishay document about shunts, I saw that temperature mismatch between the shunt's terminals can introduce a "parasitic" voltage drop which will in turn affects the current ...
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Highly accurate DIY friendly (cheap) power load
To avoid XY question, I start with my motivation and then my question.
I have an Emporia Vue2 (in-panel) power sensor but it is known not to be very accurate. For me there is a discrepancy between the ...
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Which INL is better for this ADC?
I am using the following ADC.
I want to know given the figures below, which INL is better?
How do I interpret the x-axis (% of FS)? What is my full-scale (FS) value? My Vin ranges from 10mV to 50mV ...
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How to design an accurate (1 μV error) meter
I want to design an accurate LV meter.
The range is from 2.5mV to 50mV both AC, with a 5uV accuracy. This comes from a shunt resistor that is connected to AC main (230V AC). Hence it will go below 0V. ...
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Long Term Drift of IC
I wanted to calculate Long Term Drift of output voltage of an IC and in datasheet the value is given as 60 ppm/√kHr. I dont know what exactly this means as there is square root of kHr. Can anyone pls ...
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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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Improvement in current sensor accuracy
I want to improve the accuracy of a current sensor. 49% of the error I have at the moment is from the tolerance of the shunt resistor and 26 percent of that it is from the op amp offset voltage.
How ...
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DC offset to an ADC reduces dynamic range which reduces accuracy. How to quantify accuracy due to loss of dynamic range?
It’s understood that the dynamic range of the ADC should match the max amplitude of the signal to achieve maximum accuracy. If it doesn’t, you lose digital codes which reduces accuracy.
How can one ...
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The most precise resistor with respect to temperature ppm
What is the most precise resistor available (measured in terms of ppm drift if
measurements are repeated over time)?
I just want a passive box with two terminals. The temperature will be kept between ...
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How much does temperature affect the 555 IC?
I read that one of the disadvantages of the 555 timer is that it varies in timing accuracy depending on temperature.
How much can accuracy vary, and why does this happen? Is temperature the only thing ...
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Why does oscilloscope high-resolution mode for acquisition show inconsistent measurements?
Question: Why I get inconsistent measurements from scope specifically in high resolution mode,
i. At cold start higher values are obtained, as time passes measurements drift (gets lesser values)
ii. ...
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How do the electrical characteristics of an ADC degrade over lifetime?
How do the electrical characteristics of an ADC typically degrade over lifetime?
And is there a way to do a somewhat realistic worst-case estimate for that before doing aging tests over a big batch?
...
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How to understand B values of thermistors for different temperature levels?
E.g. the datasheet of NCU18XH103F6SRB mentions different B values for pairs of temperatures (reference temperature to a higher one).
For reference, here the values of this chip:
[T]=degC
[R]=kOhm
[B]=...
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Improve accuracy of thermistor circuit
I am using this thermistor to measure temperatures between room temp and 100C and I want to design the circuit in such a way that it reads as accurately as possible (ideally +/- 2 degrees). I'm using ...
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Output resolution of PWM H bridge drivers such as L298N
I am working on a project which require a high resolution of the output signal of L298N or similar driver. Is it possible to control the output signal with a 1% resolution or better? What is the ...
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Acceptable overshoot, accuracy, and control bandwidth of a buck converter
I am designing a closed loop buck converter and was wondering what would be the acceptable values/performance for control parameters like accuracy, control bandwidth, and overshoot.
I know that the ...
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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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Is AC current clamp meter accuracy affected by the inner wire curving around the outside?
I have a SCT013-030 current clamp sensor I plan to use to read out the power usage of a mains AC load. It works by wrapping around one of the AC strands of wire to measure the magnetic field.
The one ...
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Why STM32 is more popular at industrial devices? [closed]
Well, I am really new started engineer to embedded system. Generally I am using Arduino NANO and its look very easy to use, low power consumtions and lots of library and etc is benefitial for me. But ...
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How do I calculate accuracy marked as ±(4 ppm rdg + 10Digit)?
Trying to figure out the correct way to calculate accuracy with LSD. I looked at a few sources, but I'm still confused on the topic.
The question:
A digital voltmeter can display counts up to 1999999 ...
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Accuracy of analog multimeters
What accuracy should I expect from an analog multimeter that cost 50$ when measuring resistance?
It's measuring 1.5 kilohm correctly, when measuring a 10 ohm resistor it's about 30% off. I tested it ...
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Find the range of uncertainty? [duplicate]
The problem says that an ammeter has a 30 mA upper measurement limit and its accuracy class is 2%.
For the relative measurement error when measuring 22 mA, I found it is2,7%. I used the formula h(%) = ...
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What does it mean by "in the range of 1000:1" for an accuracy of 0.2 in energy metering?
Most of the time whenever I come across electricity metering or CTs, there is always a term like an accuracy class e.g. 0.2, 0.5, 1, 2, etc. I have an idea about what this accuracy class means.
But ...
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How to calculate accuracy of LDO
I will be using a TPS7H1101A LDO and wanted to calculate the accuracy of it. I see in the datasheet they list the output voltage accuracy of +/- 2%.
I think this number in some datasheets covers the ...
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How can I improve the accuracy of my voltage divider?
I am designing low-cost SoC (State of Charge) evaluation software for a LiFePo4 battery cell at zero current (actually only a low current due to auto discharge). For this peculiar application, low ...
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Does using two Hall effect current sensors in parallel affect accuracy?
I am designing a circuit with allegro current sensor ACS770 for measuring currents up to +/- 90A.
I have 2 options :
use single ACS770-100B (100A Bidirectional version)
use dual ACS770-50B in ...
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SAR ADC dynamic range and accuracy
This App Note states:
To have the maximum ADC conversion precision, it is preferable that
the ADC dynamic range matches the maximum amplitude of the signal.
Assume that the signal to be converted ...
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Difference between simulator and my analysis
I have this circuit:
I have done circuit analysis and found the total current to be 21mA.
Here is what I have done:
But when I run the same circuit in multisim it shows me 20.6mA.What could it be?Am ...
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How more accurate in practice will a STM32 become if we use HSE?
Everybody talking about that HSE (External crystall) is much better than internal RC-oscillator in a STM32 microcontroller. But how much better is it and how?
Is the ADC more accurate?
Are the timers ...
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9-axis IMU for weighing on a boat with varying sea conditions
I am brainstorming on how to do relatively accurate weighing scale for fish on a boat under different seastate conditions.
I know other companies use a second load cell together with calibration data ...
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How to improve the accuracy of measured ADC voltage in a circuit connected to Vcc
The question is based on the following setup.
As depicted there is an IC to measure the real value of the 3.3V supply voltage accurately. The measured value of the 3.3V source is transferred via SPI ...
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Is measurement uncertainty 2 times standard deviation or 2 times standard error?
Textbooks and online sources often say the industry standard for uncertainty is given at a confidence interval of 95 %. This means out of 100 measurements, 95 would achieve the specified value and ...
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Accuracy of manufactured photocells (LDR) with respect to light intensity
I was looking through photocell (photoresistors) datasheets, like for instance the NORPS-12, especially the graphic on resistance value versus light intensity.
In no datasheet could I find information ...
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How to calculate measurement error in an exponentially non-linear sensor? (self made pressure sensor)
I'm trying to calculate the measurement error from a home-made pressure sensor which I have in a voltage divider circuit. It has the same negative exponential non-linear resistance characteristics as ...
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How many bits of information does a voltage of 0-5V , with accuracy of ±50mV convey?
In my intro to logical design class, we were shown this simple question as one of the first examples for the exercises we will have. The question was:
An analog voltage is in the range of 0–5 V. If it ...
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What is the true accuracy of a linear regulator or DC/DC converter design?
Normally, vendors of LDOs and DC/DC converters specify the output voltage error in the range of 1.5% to 2.5%. However, the analysis often suggests that the error can range from 3% to 6%. Lately, I saw ...
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Accurate localization through GPS, IMU and odometry
I am trying to localize a robot with an error <1m. I have XA1110 GPS but haven't tested it in an open area (due to the ongoing disaster) hence I am unaware of its practically achievable accuracy. I ...
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How to solve ADC measurement issue?
For a project, I am using the following circuit to detect the load3 change. With an 16-bit coulomb counter ADC I am measuring the current I. Using onboard Arduino Uno ADC I am measuring votage, V at ...
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ADC resolution vs Accuracy of signal measurement?
I want to get accuracy of 0.1% in the following analog signal measurement:
AC voltage in the range of 0-300V (0.1% = 300 mV)
Then what is the minimum no of bits or resolution of ADC that I can use?
My ...
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Fluctuating ADC results - is it normal and characterized in a datasheet?
As I have been reading [1], there exist four different DAC error types, which contribute to the overall error:
Offset Error
Gain Error
INL Error
DNL Error
Is my understanding correct, that these are ...
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high accuracy analog differential signal switching solutions to prevent distortion (relays?)
first let me define the application and circuit. the application of this is to sence currents ranging from 1nA to around 900mA. to accomplish this two resistors are used, a 10K for the nA range, and a ...
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Poor man's voltage reference
I want to build a voltage reference based on LM4040 (A series 0.1%), the output voltage is switchable with a selector switch:
simulate this circuit – Schematic created using CircuitLab
...
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Use of ADC Bits below noise floor
I have a Sigma Delta Modulator with a SINC3 Filter. The System runs at maximum oversampling possible for this application and I know my (Full Scale Signal)ENOB for this szenario to be 14.
Is there ...
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Why is there a discrepancy in the E192 series? [duplicate]
For all series from E48 through E192, this holds true:
$$
value = 10^{\frac i n}
$$
where i is the zero-based index in the series and n is the length of the series. The one exception is E192[185]:
$...
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