All Questions
Tagged with measurement adc
55
questions
0
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2
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65
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What is the real resolution of my voltage measurement when I use only some of the range of of the ADCchannel
I have a 16 bit ADC, I use the +/1 V range, differential channel. If I used the full range of the ADC to provide full resolution (I am aware non-linearity and noise may affect this) this calculates as:...
- 11
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0
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28
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Understanding Voltage Read in Voltage Divider for NXP S32K118 Microcontroller ADC
I am having a bit of a hard time understanding the voltage read in the voltage divider that is being an input for an ADC to an NXP microcontroller, S32K118. Below is the schematic of the circuit.
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votes
1
answer
127
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Sigma-delta modulator (ADC), can it be used without sinc3 filter?
Purpose: isolated measurement of DC voltage (about 600V).
For these purposes, I found two options:
ADS1115 (I2C ADC) + I2C digital isolator
CA-IS1204 Isolated Sigma-Delta modulator
I am considering ...
- 535
2
votes
0
answers
28
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Is it necessary to implement a sensing resistor plus pre-amp with Faraday cage on a PCB if I would like to have the range about 10nA measurement?
I put a 60 kΩ sensing resistor plus low-bias current amplifier with a gain of 500 into an aluminium bag and tied it to AGND for EMI shielding. The second stage is an ADS1256 24-bit ADC. The purpose is ...
- 89
6
votes
4
answers
675
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Precision current source and mΩ measurements
I'm trying to measure some resistors in the 3-5 mΩ range. I want to use a precision current source (picture below) and an AD7791 ADC for that purpose. I also want to use a 1.2 V reference voltage (...
- 151
0
votes
1
answer
204
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How does the FDC1004 (capacitance to digital converter) measure capacitance?
I am using the FDC1004 and wondering how it exactly measures capacitance. The datasheet is not explaining much. An associated application note contains a little more information, but still very little ...
- 285
0
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2
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175
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Which variations of the flash ADC is correct?
The flash ADC I learnt in class is this one with R all of the same value:
I found different variations on the internet:
This one has the top resistor with 3 times the value of other resistors.
This ...
- 1
0
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0
answers
230
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Minimize the quantization error of transducer and DAQ
Can somebody please let me know how to solve this problem:
A 12-bit A/D converter has an input range of ± 10 V and is connected to an input amplifier with a programmable gain of 1, 10, 100, or 500. ...
1
vote
1
answer
183
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Number of data points needed for INL DNL estimation
In this article where ADC of pico pi is characterized, I found a part that I have never encountered in my study of mixed signals design:
I don't understand how we number of data points needed is ...
- 261
0
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0
answers
97
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Acceptable SNR for a Sound Level Meter
I'm designing a low power (<150mW) sound level meter (SLM) using a 24bit ADC (preliminarily using the LTC2512-24). This is for audible frequency range signals only (20Hz - 20kHz). I'm focused on ...
- 439
1
vote
1
answer
272
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DC bias for AC measurement with an Arduino
I'm trying to make an AC and DC voltmeter with auto-ranging and auto-switch (between AC and DC.) The maximum input is 0~24VDC and -24V~24VAC. I've built a voltage divider with some optocouplers ...
- 11
0
votes
3
answers
1k
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ADS1115 ADC input filter - active or passive?
I want to implement an ADC as part of my bachelor's thesis.
The datasheet of the ADS1115 show that there is no filtering done by the ADC chip before the multiplexer. As I read here, it is good ...
- 850
1
vote
4
answers
2k
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How to calculate measurement error in a voltage divider?
I'm trying to calculate the measurement uncertainty of the voltage represented by the ADC in +/- V or % of a voltage measured across R2 of a voltage divider.
What would be the general way to tackle ...
0
votes
3
answers
2k
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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 ...
- 139
0
votes
0
answers
633
views
Loadcell strain gauge with 10 V excitation
I am designing loadcell (spec) measuring using 24-bit adc (MCP3561) with excitation 10 V. But I couldn't find the reference design for 6-wire loadcell that its sense pins connect to ref+ pin of ADC. ...
- 61