I want to interface a 4-channel, 24-bit, 1Ksps, ADC with Arduino. Has anyone experience to help me? What Arduino version should I use? (I will need to store the measurements on a SD card). Also which ADC is capable for interfacing with Arduino? What should I take care of the ADC? I need a DIP package because I am going to solder it, not a machine. I would be grateful if you could give your opinion/experience....
Have a look at the numbers - will an Arduino take all that data for a long enough period of time ? You need to look at that first.
What’s the project? Why 24 bit? - is there another way ?
There are some 24 bit load cell amps about hx711(?) strain gauge amp/A-D for which handy libraries exist , but not available as a dil package .
A quick search came up with this :
hammy:
Have a look at the numbers - will an Arduino take all that data for a long enough period of time ? You need to look at that first.
What’s the project? Why 24 bit? - is there another way ?There are some 24 bit load cell amps about hx711(?) strain gauge amp/A-D for which handy libraries exist , but not available as a dil package .
A quick search came up with this :
ADS1252: Tutorial on High precision (24-bit) ADC - Sensors - Arduino Forum
I want the biggest resolution it can be...
Plenty of bits and high resolution is of cource nice, beautiful etc..
What resolution does Yorur project really need?
Why spend millions buying the best mesasuring devices provided if some thinking tells that quite standard equipment would be enough?
Will the noice levels be low enough to make all the extra bits worth the effort?
Is it so difficult to communicate a 24-bit ADC with Arduino?
This kind of equipment does for what I want to make?
1 kHz of sampling and storing on an SD card at the same speed calls for processor capacity. Maybe there is an Arduino, ADC and SD card that can make it. I don't have knowledge enough to tell.
But still, what resolution do You really need? Why spend all the effort?
What resolution is good?
Your chain of thoughts starts in the wrong end, the beginning. Look at the result You need to achive, the end, and get stuff needed for that, not a lot more giving You, and us, a lot more work.
Apart from the resolution, what other things I should look at by interfacing an (external) ADC with the Arduino? Are there any schematics to start from?
There is no way you will get true 24 bit resolution in a digital system like the Arduino without ultra good design. Most likely you will have to go to a stand alone system designed to properly keep the noise down and isolate the analogue side from the digital side.
Otherwise you will find your extra bits are just full of noise.
Grumpy_Mike:
There is no way you will get true 24 bit resolution in a digital system like the Arduino without ultra good design. Most likely you will have to go to a stand alone system designed to properly keep the noise down and isolate the analogue side from the digital side.
Otherwise you will find your extra bits are just full of noise.
To keep the noise down, I assume some kind of BandPass filter?? How do I isolate the analog side from the digital side?
I assume some kind of BandPass filter?
No.
You need a low noise layout and design. You can’t just throw these together is is a specialised skill requiring at lease a double sided PCB and all the supply decoupling techniques you can throw at it.
I certainly would not be confident I could do this myself.
Also, if I can manage the gain with an external IC, or it is part of the ADC?
or it is part of the ADC
No.
But look, once you start adding an amplifier that adds noise to the signal and in order not to degrade things any further you have to make sure the noise is lower than the least significant bit in a 24 bit word. Thus making an almost impossible project fully impossible. Amplifiers of this noise figure are very very expensive.
Thank you, can you suggest one, two to take a look? Surely I can google it, but what is the "mainstream" on this? In order to find some forum support...
24 bit times 4 channels times 1kSPS is about 100kbps. Not trivial but doable. But you either do not need such speed and precision or making the analog part work will be much much more difficult. You must start at the analog part and get a suitable MCU when you know your requirements. You may try to start with Arduino Uno onboard 10 bit 6 channel ADC.
Thank you for the advice, but I need a 24-bit ADC, 4 channels with 1Ksps, with adjustable gain...
Has anyone experience with this?
Buy that module, test it thoroughly and tell us how well it works.
alex5678:
Thank you for the advice, but I need a 24-bit ADC, 4 channels with 1Ksps, with adjustable gain...Has anyone experience with this?
No but from Datasheet:
- You can sample only one channel at given time, not 4 simultaneously.
- You can get either high resolution or fast sampling rate. Not both.
The device will likely not work for your mysterious project.
Generally are there ADCs, for Arduino, that can operate 4 channels simultaneously?