An ADC is an Analog to Digital Converter. This device converts analog signals into digital form. It is mainly used by the digital circuitry to take analog measurements.
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Using a Piezo sensor to detect audio frequency
I recently posted here without much success on this subject but I've moved forward a bit and got stuck, again!
I have Raspberry Pi and a MCP3002 ADC chip because RPi doesn't have any analog pins.
I ...
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0answers
9 views
Xmega128A1U ADC Example Code
I'm new to Xmega. I want to read the 4 ADCs of ATXMEGA128A1U in the rate of 500KHz ( 500K Samples Per Second ) with Timer/Counter interrupts of Xmega( because I want to have a good timming in my adc ...
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20 views
About coherent sampling
In Coherent sampling, it states the condition for coherent sampling is given by
$$
\frac{f_{in}}{f_{s}}=\frac{M_{cycles}}{N_{samples}}
$$
Where \$N_{samples}\$ value must be a power of 2 and ...
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1answer
55 views
External ADC Vs. Internal ADC
Why do we need an external ADC when there are microcontrollers available with internal ADC?
I think it makes it economically expensive to add to 2 chips separately on the PCB, adding peripherals, ...
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2answers
99 views
Which microcontroller pins should i use with this project?
I have some knowledge about Arduino, but it's my first time using solo microcontrollers and this sort of thing, i have no idea of what i should do in this case.
I'm following a guide that users ...
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2answers
51 views
Sampling rate analog to digital converter
I am a novice in microcontroller subject and have just learned that ADC converts analogue voltage on a pin of, for example, an Arduino, to a binary number. Since the ADC on the Arduino is a 10 bit ...
2
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1answer
58 views
Increasing voltage maximum value from 10 mv to 5v
Since microcontrollers usually don’t have specific ports for measuring currents, but they do have ADC channels through which you can measure analog voltages of a certain range. This means a dc current ...
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1answer
61 views
How should I power an ADC?
I am designing a PCB for reading analog signal by the AD7732. I searched a lot to find tips which increase the precision and effective bit resolution. One of these tips is to segregate analog power ...
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73 views
ADC in differential mode
I am trying to make a digital voltmeter with atmega16. I wanted to use ADC differential mode that ADC0 pin works as positive input and ADC1 pin as negative input(ADMUX4:0=10000) and port D , portB.0 ...
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1answer
100 views
What do they mean in ADC datasheet?
I have an analog signal in the range of -12v to +12v and I want to read it by a high resolution ADC. In other words, I do not want to use a resistance divider or other scaling methods such as op-amp ...
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1answer
29 views
ADC chip signalling - ADS4245
I am designing a system with the ADS4245.
My requirement being a 14bit,dual channel I/P and a max of 125MSPS. I understand that going higher without the capabilty to program or select an output ...
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1answer
36 views
Interfacing VoltageREF IC with the ADC
In a Battery Charging application, i am using ADS8319 ADC from Texas Instruments for digitizing the charging voltage and current signal, and providing it to the Microcontroller via SPI interface. ...
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1answer
56 views
PIC MCU: Two ADC inputs help
So currently mucking around with the ADC on my PIC16F917. I got single button functions going and all works well.
What I'd really love help with, is how to make the MCU accept 2 inputs, without the ...
6
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2answers
579 views
Adding an anti-aliasing filter to op-amp before ADC
I am designing a circuit that is intended to capture audio samples from multiple channels for sound source localisation.
Each channel has the following 2 stage op-amp circuit, before going into a ...
5
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2answers
433 views
In an ADC what are the units of resolution called?
I have a signal whose full scale output on the 12bit ADC is 4095. If I reduce the signal so I see the output number is (say) 4000 the output has decreased by 95. But 95 what? What are those divisions ...
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1answer
63 views
Strange result ADC(Arduino Micro) Thermistor KTY 10-6
Where's the error in the following circuit/code ?
Some time ago i got various sensors . One of those was the kty 10-6 (3 pieces). At the beginning i could not find any datasheet or examples about ...
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1answer
23 views
How calculate standard deviation of ADC histogram for rms noise analysis?
Some papers from Analog Devices (like this one - page 2) and other sources indicates that the rms noise of a histogram plot of an ADC output can be found by calculating the standard deviation of the ...
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2answers
50 views
Piezo into 0-5v ADC, with offset center voltage?
I want my piezos to have a center voltage at 2.5v for a 0-5v ADC input on Atmega328, so it can sense force in both ways - one way would be >2.5v and the other will be <2.5v.
Will this circuit ...
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1answer
45 views
Resolution of Oversampling Converters
This is a question from this application note:
http://www.atmel.com/images/doc8003.pdf
In section 3.2 on noise it says that adding some amount noise into the signal helps in increasing the resolution ...
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1answer
41 views
MCP3008 (ADC with SPI interface) what to do with unused pins?
I'm building embedded system based on a Raspberry Pi with an MCP3008 for analog inputs. I have few questions regarding the PCB board design.
What should I do with unused analog inputs on my MCP3008?
...
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3answers
74 views
Interfacing Current shunt monitor with 16bit ADC
I am supposed to high side current measurement via shunt resistor (between source and load) and feed it to the microcontroller. For that purpose i have decided to use this IC MAX9922 which is a ultra ...
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1answer
40 views
Delta Sigma Converters: Resolution
This question is in reference to my earlier question:
Resolution gain in Delta-Sigma Converters
What I understand
From the answers I inferred that we need the input to have some amount of noise (to ...
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2answers
126 views
Resolution gain in Delta-Sigma Converters
Suppose I have a two bit quantizer with the following voltage levels: [0 0.2 0.4 0.6]. Thus 0V corresponds to bits 00 and 0.6 to bits 11. Suppose I use this quantizer in a first order delta sigma loop ...
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1answer
66 views
How can an ADC measure below its resolution?
An ADC's resolution is set by the maximum input voltage divided by 2b where b is the number of bits. In that way, a 16-bit ADC with 20V input can measure a voltage of 20/65536 = 0.3mV (corresponding ...
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2answers
49 views
Is programmable gain amplifier(PGA) in ADC enought to get me precision
I have 4 x 3wire load cells from a old weight scale connected as a full-bridge and I want to connect them in my uC ( Atmega328P, but not arduino ).
I want to measure weight under these specs:
...
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1answer
39 views
ADC speed for precision medical instrument
I am studying a bio-medical instrument where glucose in blood is measured using light reflection principle as shown:
Below equation is used to determine glucose level:
LED is blinked at fast rate ...
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1answer
72 views
ADC conversion using a Datasheet
Is it possible to find a corresponding digital value for an analog current value(Amps) using the ADC component datasheet? If yes, what are the parameters I should consider?
Thank you!
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3answers
309 views
MSP430 program only works during debug mode
I am trying to retrieve the values from the ADC on my MSP430F5529 and send them to my computer over USB, but I am starting small. All I have right now I something that retrieves the ADC value and ...
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1answer
52 views
Which ground (digital or analog) measurement components should be connected to?
Good day,
I want to measure current and voltage of switching power supply that is on board together with ATMEL AT32UC3L microcontroller.
I think I understand how to measure - using resistor divider ...
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1answer
52 views
How to check IC chip?
I am currently having problem with the Analog to digital conveter IC ADS1230. It used to work perfectly fine on the PCB, but now I am not getting any data. So I was wondering if there is any method to ...
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1answer
42 views
PIC24F: problem in AD1PCFG register
Im working ADC in PIC24FJ64GA002 microcontroller using proteus simulation. I've a doubt regards AD port configuration register. I've connected a potentiometer in AN12 pin and channel was selected. The ...
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0answers
31 views
AT90USB646 code 43 error
I needed adc for my project so i built this :
It was programmed correctly but when I connect the USB to the PC to use Codevision terminal nothing happens and there is Code 43 usb unrecognised ...
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0answers
105 views
Op-amp not amplifying voice from electret microphone
I've tried this schematic (taken from the answer of this question) on my breadboard:
Except, i have changed:
R1 to 9.4K(4.7K*2 in series);
C2 to 47nF;
R5 and R6 to 220K;
VDD = 3V3;
Opamp: LM358 ...
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2answers
81 views
High Precision ADC/DAC Circuit Feedback
This is my first proper circuit I've designed and I'm after some advice.
I need a 16 bit DAC, output 0-5V and I need to measure the resistance of a thermistor to 0.1mk accuracy. At the moment, I am ...
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2answers
60 views
Wrong voltage in op amp circuit to adc
my circuit is not giving me the expected voltage. This is used to measure the current flowing trought the shunt.
For example: if I expect 1.3, I get about 1,15V out. Anyone knows what I did wrong?
...
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2answers
55 views
I need to sample 8 audio sources at audio quality, what MCU can I use? [closed]
I need to sample 8 audio sources at the same time, at a decent frequency (say, 40Khz). Being only familiar with Arduino, I searched online for tutorials and articles about using interfacing it with ...
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0answers
16 views
atmega32 piezo detect knock
I am trying to hookup a piezo sensor to an atmega32 and detect a knock.
From the following website I took the example for the connection:
https://www.arduino.cc/en/tutorial/knock
Except I am not ...
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3answers
75 views
How to measure H-Bridge motor voltage using ADC
I am controlling two motors using a double H-bridge controller. I would like to measure the voltage at each motor using ADC's on the microcontroller. The problem is that the motor voltage may be ...
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0answers
33 views
Switch Mode power supply and ADC measurements
I've got a controller, measuring on 4 channels, but I see the (~50mVpp)ripple of the power supply, when I oszilloscope the ADC pin. The adc values jump around too. I tried to add an LC filter, but it ...
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1answer
47 views
Choosing ADC with wide input voltage range (0-10V)
I faced with the task to measure several inputs (0-10V analog) with galvanic isolation.
Using plain Google search (like '0-10V adc') I found several solutions like Linear Technology LTC1854/55/56 ...
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0answers
22 views
Connecting a load cell to TIVA C Launchpad
I have a typical 4-wire wheatstone bridge type load-cell. 2 of the 4 wires are for excitation called E+ and E-, while the other two wires are for sensing S+ and S-.
The load cells are generally ...
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1answer
30 views
Negative input voltage on Isolated Differential ADC
I am trying to interface with negative voltage input signal ranging from -5V~5V or -10V ~ 10V.
Since the input signal may be floating or have ground reference, I am planning on galvanically isolating ...
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2answers
46 views
Why does this work for biasing an AC signal for A/D conversion
I have a working circuit for biasing the AC signal going into my ADC, but I cant quite wrap my head around why it works. I can see that it resembles a high pass filter but how/why does it add the two ...
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0answers
22 views
Interfacing a differential thermocouple pair with ADC
I have a differential thermocouple pair (two K-type thermocouples connected by a common leg) from which I need to sense very small temperature changes between the two thermocouples. Because one ...
0
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2answers
56 views
would using the reference voltage of an ADC as a VOLTAGE SOURCE affect my ADC or the stability of the circuit?
I am using an Arduino to capture an AC signal. However, the application is sensitive and needs a high resolution, I decided to use the internal 1.1 Volt as a voltage reference for the ADC.
In the ...
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1answer
66 views
How to program the ADC10 on an MSP430G2553?
I am currently writing my first serious application with an MSP430 controller (specifically, an MSP430G2553) and I am a bit confused by the documentation as to how I'm supposed to set up the ADC10. I ...
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38 views
Conditioning negative ADC voltage with separate AGND and DGND
I was looking to condition a negative voltage analog input for an ADC and I saw these two posts describing a voltage divider circuit to do so.
How do I sample a -2 V to +2 V analog signal with a PIC ...
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1answer
83 views
Phase Sequencer
I have 3 phase voltages entering into my PIC ADC (3 different channels ) through a voltage down scaling circuit and I have successfully calculated their rms values inside my controller.Know I want to ...
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1answer
47 views
Effects of restricting most significant bits
So i have calculated the settling time for the capacitor C in an RC circuit. The RC circuit is the result of connecting an ADC with a mutiplexer. The ADC is a 12-bit type.
In the assignment ...
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0answers
64 views
why my DAQ signal is a noisy signal?
background:
My goal is to use an Arduino with two proximity probe (sensors) to achieve some output.
It is worth mentioning that the output of the proximity probe has two components:
DC output that ...
