Questions tagged [adc]
An ADC is an Analog to Digital Converter. This device converts analog signals into digital form. It is mainly used by digital circuitry to take analog measurements.
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STM8L DMA and ADC out of sync
I have STM8LDiscovery (with STM8L152C6T6 CPU). I need to continuously read 2 ADC channels with writing the data to the memory.
I'm doing my project in IAR EW for STM8 v. 3.11.4.
I run into the problem:...
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Questions about data rate, sampling frequency, oversampling and bandwidth when using an analog front end IC
I have an MCP3911
which is an analogue front-end with the following specifications I have a few questions about:
Programmable data rate up to 125 kSPS - 4 MHz maximum sampling frequency
Oversampling ...
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Not printing correct values [closed]
So I wanted to read the ADC values and put them out in voltage form through UART.
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What is the HX711 measuring?
I've read the library for the HX711 Avia Semiconductor, and I don't understand the read() function.
From what I can tell, the other functions use ...
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Measuring AC motor load with CT clamp
I am trying to measure the load in an AC induction motor with a current clamp and ADC. When using a clamp multimeter I get a value of 3.6 A when the 5.5 kW three-phase motor is running without load.
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How to improve ADC reading accuracy from 1mV to 0.1mV or better
I want to read a DC voltage from a battery with 0.1mV resolution or better and send the value to a PLC based in Arduino Mega. I selected an ADS1115 (datasheet here) which has enough resolution to do ...
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Is reading multiple buttons presses with ATtiny analog input a reliable method?
I need to read the input from 8 different push buttons on an ATtiny microcontroller.
After researching how to do this with the least number of pins, I found out about using a voltage divider with ...
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STM32 Nucleo-F302R8 incorrect ADC readings (HAL)
I am trying to use the STM32 Nucleo-F302R8 board's ADC to read the voltage output of a TMP36 temperature sensor, but I am reading values which are very different from what I should obtain. Namely, ...
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ADC channel customization in F28335 control card using Simulink
I'm using the TMDSHVMTRPFCKIT with a TMDSCNCD28335 control card for motor control.
I would like to change the ADC channel assigned by the manufacturer as shown in figure 1 to values shown in figure 2.
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How to design a schematic and PCB for an ADC using separated grounds
I want to measure a DC voltage with very high resolution (uV) and send the value to a PLC (based on an Arduino Mega.)
Initially I selected an ADS1115, but I got some power noise due to loop currents (...
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ATTiny1616 ADC - issue with input channel switching
I am trying to configure Analog-to-Digital converter in ATTiny1616 to switch its input source between internal voltage reference and external input signal. My issue is that when ADC1 is adequately ...
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How to put MCP3008 into sleep mode
I am using an MCP3008 ADC connected to a Seeed Studio Xiao nRF52840.
I am using the adafruit library #include <Adafruit_MCP3008.h>
It operates as expected, ...
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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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How to calculate the cut-off frequency of a software average filter
I want to read the voltage of a battery using an ADC connected to a PLC. The signal oscillates a bit and I want to smooth it. The ADC samples the signal at 860 samples per second and stores it in ...
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Current Sensor accuracy Calculation
I wanted o calculate current sensor accuracy of 0 to 80A current detection circut showed in attached figure. I want to simulate in LTspice with diffrent values of reistance tolarences and this circut ...
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STM32 SVPWM switch timing algorithm
I am designing a 3-phase to 3-phase matrix converter modulated using SVPWM on an STM32F767ZI and I am wondering how you guys would recommend I design the following timing algorithm:
Figure 12 above ...
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Differential Input to ADC Depends on Mac vs Windows Laptop USB Power (ADS1115)
The Problem
I have a vacuum gauge that I would like to read and report the values from. The gauge expects a 9-30VDC input power, and has pinouts for Analog+ and <...
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Interface ADC with STM32F103 over SPI
The ADC is ADS1256 which is a 24 bit 8 channel ADC. I will use 1 kHz sampling rate and there will be 3 ADCs, 21 channels used in total. The channels will be single ended. I plan to run the MCU on a 40 ...
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How to measure the peak region of an AC voltage using an ADC
I am wanting to measure JUST the peak voltage region of an AC waveform i.e. like the top 20 volts of a 130 volt 100kHz waveform.
I want to limit the measurement to just the peak region so that I can ...
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STM32 Strange behavior of ADCs in alternate trigger mode
I am using a STM32H723ZG board for a project. In this project I must sample the signal coming from an image sensor that sends the pixel values as pulses with analog amplitudes. This sensor also ...
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Reading two 16 bit ADC with two MISO lines each for its two channels using an STM32H723ZG
In my current project I am using a STM32H723ZG Nucleo board on a custom shield PCB with two AD7380 ADC's which amount to 4 signal channels.
The goal is for the next PCB revision, to read out all 4 ...
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How to simulate sigma-delta ADC pulse train in LTspice
I am trying to simulate a complete current sense path of a motor phase, right from the shunt resistor to the MCU in LTspice.
We are using an AMC1303 (50 mV differential)(MPN: AMC1303M0520DWV) sigma-...
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How to buffer (high input impedance required) a differential signal
I'm wanting a to increase the input impedance to a differential ADC. The ADC spec states that it can't handle a negative voltage lower than -100mV the ADC's supply can handle ~5V (this is a ATtiny1617)...
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Collecting photodiode current in specific capacitor
I want to be able to measure the amount of light that hits a photodiode during different timeslices specified by particular signals. For example, below when S1 is high I want C1 to charge, and when ...
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Input filtering and protection for instrumentation amplifier (2x ADA4528)
I'm currently trying to measure the load cell output using AD's circuit note CN-0216 "Precision Weigh Scale Design Using the AD7791 24-Bit Sigma-Delta ADC with External ADA4528-1 Zero-Drift ...
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What should be done with unused input of an LM339 and LM358? [duplicate]
I am designing a circuit using an LM339 and an LM358, and I am not using all of the contained comparators or op-amps. I searched through the datasheets, and they did not explicitly state what should ...
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Converting from ADC to real voltage
I would need to calculate initial voltage from ADC reading.
I'm a bit confused from the 3.3 V after the voltage divider.
Basically I have a voltage can vary from -12 V to +12 V on input and ADC is ...
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How do I convert an input of -1 V ... +1 V to an output of 0 V ... +3.5 V using an MCP6022? [closed]
In the simulator I get the expected result:
input: 1 V
output: 2.10 V
But when I use hardware I don't get the correct output voltage.
Can anyone give me answer with best example?
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MAX11645EUA+T ADC Readings
I am having issues with ADC readings with MAX11645EUA+T. I have a 2 input ADC and am driving the inputs with thermistors buffered each with a voltage follower. The ADC works when I have both ...
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Can I use one voltage divider for multiple voltage comparators?
I have a circuit that uses multiple comparators, that are comparing the same threshold.
Could I use just one voltage divider for all of the comparators, or if I need a sperate voltage divider for each ...
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Output of ADC when no input is supplied
I am working with a Raspberry Pi 3b+ connected to an MCP3008 ADC to read sensor output.
When the sensor is not connected it gives some floating value (max. value). Is it possible to get a value of ...
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Injection current with ADC
I am using this Controller & I see that the clamp current mentioned on page 706 is 20mA per IO pin.
I was not able to find any value that would indicate the maximum allowable clamp current for the ...
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How can I measure voltage with this circuit?
In our company, we have developed our own ampere-meter that transfers the measured data to a PC via USB. An employee who no longer works for us created this. The circuit board of the measuring device ...
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ADC injected method using STM32
I need some clarification about ADC in injected conversion method. I am using STM32F103C8 controller I configure TIM1 in center align mode 1 to trigger the ADC in injected mode. i worked well and ...
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How to measure voltage with lifted ground?
simulate this circuit – Schematic created using CircuitLab
MCU1 is factory and I can't modify its firmware. I need to add a second MCU2 (ESP32) to control existing 4-20 sensor. Which ADC can I ...
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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 (...
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Quad slope ADC and dual slope ADC
I know that the output of a dual slope ADC doesn't depend upon the value of the resistor and capacitor used, so its output is accurate. How does a quad slope ADC work? How is the output of a quad ...
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STM32 maximum ADC frequency
I am using a STM32H723ZG board for a project and I must read analog signals so I am using one 16-bit ADC. Based on the datasheet of this microcontroller serie, the maximum ADC clock frequency is 50 ...
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Download ADS8321 in LTspice
How can I download ADS8321 in LTspice? If it's not possible, can you suggest an alternative?
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Op-amp use in voltage sensing
For voltage sensing, we use a resistor divider and then we always feed that value of the resistor divider to an op-amp and then the op-amp output is fed to a microcontroller.
What exactly does the op-...
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Which SUBCKT to use (TI ADS9110) Orcad PSPICE
I am new to this simulation, and try to simulate the ADS9110 (TI ADC) using Orcad 17.4.
The TI has the PSPICE Model here: https://www.ti.com/product/ADS9110?keyMatch=ADS9110&tisearch=search-...
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ESP32 ADC pins reading non-existent voltage
I was working on a project with the ESP32, where I need to read a few voltages and switch LED colors accordingly. My problem is that after flashing my board, the GPIO pins 13, 27, 33, and 34, all read ...
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I have three absolute rotary encoders that can output analog sinusoidal voltages OR SSI signals. I need to send their signal to a single pin. How?
The rotary encoders I'm using are sold with several different output options. Analogue sinusoidal (90* phase shifted sin and cosine signal), Incremental output (90* phase shifted quadrature signals ...
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STM32: two independent ADCs for fast sampling with external trigger
I will give you some context about what I am doing and my problem:
I am using an STM32H723zg board to read and process analog data coming from a sensor. This is an image sensor working at 8 MHz and it ...
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Finding resolution of quantizer with both corrupted input noise and quantization noise
I'm trying understand how to find the bits required to get a quantization noise of 32 dB from an input signal that is already containing some noise due to corruption.
If the input signal is already ...
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ADC settling time
According to TI's Switched-Capacitor ADC Analog Input Calculations application note you can select resistor Rs such that the signal settles within an error band given sample time Ts.
Once one has this ...
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STM32 ADC sinewave samples looking choppy and block-like despite high sampling rate
I'm trying to read a sinewave off from my signal generator with STM32 ADC and reproduce the same wave on my DAC, this is the result
This is what my wave looks like in low frequency about 300 Hz
and ...
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STM32 Start ADC with timer in one-pulse mode
I need to start an ADC reading with a fixed delay in different places in my code. It should be done with a timer and once an update event (overflow) is generated, the timer should be stopped and reset ...
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Are ADC errors and noise RTI or RTO?
Are ADC errors like DNL, INL, Offset Error, Gain Error and Noise specs given in data sheets RTI or RTO?
The units are LSB so it makes me think they are RTI.
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