Hello Dear Friends,
Not a long time ago i discovered for me beautiful Arduino world, it is amazing.
I want to take it to the world of measurement from sensors in my lab.
I have some questions about Maximum signal bandwidth in analog input.
Lets say i have sine signal with 'x' frequency, to sample it i need at least '2x' for nyquist sampling frequency. What are the maximum sample frequency Arduino can handle? and what about maximum signal bandwidth?
Please refer my question for simple boards like UNO R3.
Thanks you.
I think the maximum sample frequency for 10bit samples is about 10,000 15,000 samples per second. You can get higher rates if you are prepared to accept 8 bit samples.
You should study the Atmega 328 datasheet which has all the details.
...R
You can get samples out of the ADC quite quickly - 70 .. 80KHz is possible without compromising the accuracy too badly, and even faster if you don't care about accuracy - but this requires accessing the ADC hardware directly and bypassing the Arduino analogRead API. However, at the higher frequencies you have very little time to deal with each sample.
Ok Thanks for prompt answers,
So lets say some signal with 10khz bandwidth will be sampled with no problem with pretty good accuracy?
P.S i wonder where i get more documented information from ADC datasheet?
So lets say some signal with 10khz bandwidth will be sampled with no problem with pretty good accuracy?
No.
You will get 5KHz at 10 bits accuracy. I would not call that pretty good.
Now what are you going to do with all those samples. There is only 2K of memory (RAM) for the whole processor so you have about 1.5K free for an array that is about 0.15 seconds of data. Is that enough for you?
i want to store it to SD card (with shield).
why 5KHZ? i see from Atmega datasheet (ADC conversion time maximum 13 micro sec, so it is near 75khz frequency)
lets say i will sample it with fs=3B so Bandwidth can be maximum 25KHZ
Am i missing something?
I made a mistake earlier. The datasheet says 15ksps at maximum resolution (I said 10) and 76.9 at lower resolution.
As I understand it, bandwith is a fraction of the sps rate.
...R