Questions tagged [sampling]
Periodical measurement of an electronical property of a system, most often voltage.
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Differences between Interrupts and sampling for hardware button?
I have a hardware button I connected to an interrupt, but my problem is it bounces a bit, making the button press unreliable. I think a good deal of these issues would be solved by sampling in the ...
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Maximum sample rate of Arduino Duemilanove?
G'day all!
I have an Arduino Duemilanove hanging around spare at the moment and thought I might try a few audio interfacing projects. I'm just wondering what sort of sampling frequency I can achieve ...
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Oscilloscope: How are Bandwidth specification and Sampling Rate related?
I had thought that a (digital) Oscilloscope with higher Sampling Rate, would automatically have higher Bandwidth. That seems intuitive because of Nyquist Sampling Theorem. But I've read in several ...
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Sampling Rate Passband Signal
What is the maximum/minimum possible sampling rate for the signal to be full recovered for a passband signal?
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Why are digital oscilloscopes still so expensive?
I'm a beginner in hobby electronics and I am wondering
why digital oscilloscopes are still so expensive?
In times of cheap GHz CPUs, USB 3, ADSL modems, DVB-S receivers, blu-ray players which all of ...
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Why is the Nyquist data rate lower than the Shannon data rate?
In the book Computer Networks, the author talks about the maximum data rate of a channel. He presents the Nyquist formula :
C = 2H log\$_2\$ V (bits/sec)
And gives an example for a telephone line :
...
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Exactly what is the role of the zero-order hold in a hybrid analog/digital sampled-data system?
I'll admit, I am asking this question rhetorically. I am curious what answers will come back out of this.
If you choose to answer this, make sure you understand the Shannon-Nyquist sampling theorem ...
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ADC outputs random values to constant input
I am using ADC (ADS7822) from TI and I have some strange behaviour with it. Below diagram explains the voltage inputs and connections.
I was reading strange values with this setup.
I removed signal ...
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How to sample audio at Nyquist frequency with MSP430F5438?
I want to:
Input an analog audio track
Using the microcontroller ADC, convert it to a digital output
Then have the microcontollers/boards timer sample the data at selected intervals
Resample the "...
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Measuring low current at very high speed
I have a circuit with a very-low-power Jennic JN5148 module with microcontroller and 2.4 GHz radio, and some low-power sensors.
I have to measure the supply current of all these components, in an ...
3
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Weird samples from SAR ADC
I am playing around with some SAR (Successive Approximation) A/D-converters. I have made a test circuit where I have a 16-bit DAC from Texas Instruments (R2R-based) and an 16-bit SAR ADC from Analog ...
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PIC analog to digital converter to measure more than one battery voltage (with different grounds)
I'm trying to build a circuit that can scale down several lipo batteries (5 cell) up to 22V max to be safe to either 3.3V or 5V for measuring with a PIC microcontroller using the analog to digital ...
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Does SNR improve at higher sampling rates for a low pass filtered signal?
Let's say we want to extract 1Hz signal from a noisy signal by using a LPF.
And assume we have sampled it with 100Hz sampling rate.
If we would have sampled it with 1kHz sampling rate and use the ...
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1
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Calculating 3-phase real and apparent power using sampled signals
Using step-down/isolation transformers, I am sampling the phase-to-phase voltages of a 3-phase, 3-wire industrial utility system in the US (208Vrms, 60Hz). Additionally, I am sampling the line ...
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What does "two signals aliasing to each other" mean?
So I just read something that two signals are aliasing to each other. I know what a single signal is being aliased - that is when sampling rate is not higher than or equal to the Nyquist rate. But I ...
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Sampling bottleneck due to sensor conversion time? MAX6675/MAX31855
The datasheets for the MAX6675 and MAX31855 say that their "temperature conversion times" are 220 ms and 100 ms respectively.
I am using an arduino to get the data from a K-type ...
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Delta Sigma Modulator for 2/3 Multi modulus divider used in FracN PLL
I have been trying to implement a Delta Sigma modulator for a 2/3 Multi Modulus divider. I am referring to Riley's paper: https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=229400
I have designed ...
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MOS Amplifier Circuits with Feedback
The following images show NMOS amplifiers circuits with feedback:
a)Transconductance (tension source, current output (RL)) -> current sampling, tension mixing
b)Transresistance (current source, ...
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sampling rate and frequency response of a vibration sensor
I am trying to measure the vibrations of a lathe machine using a piezoelectric accelerometer sensor. I want to know if the sampling rate can be set at a value greater than the flat response frequency ...
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minimum readable rise/fall times in an oscilloscope
How can I calculate minimum readable rise/fall times of a signal in an oscilloscope (from practical point of view)? Does it depend just to bandwidth and sampling rate of oscilloscope? regards
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Why is the STM32 reference manual stating the wrong sample frequency for I2S?
This could be a misunderstanding but everything I have gathered and seen it looks like there's a disconnection on what the reference manual says.
On Pg. 2212, in the STM32H753ZI it states:
"The ...
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How is the filter response affected by the sampling rate?
At this filter, the sampling frequency is changing the output bode plot.
I have never thought this before. What is the explanation of this?
edit: will be updated soon!