ADS1202: Too much noise

Hi Maria,

Welcome to our e2e forum!  The ADS1202 datasheet plot uses 256 OSR with a sync 3 filter, are you using the same in your digital filter?

Hello, Tom,

Thanks for your advise. I implemented sinc3 filter programmly according to "Combining the ADS1202 with an FPGA Digital Filter for Current Measurement in Motor Control Applications". But noise is still too high.

Hi Maria,

If your filter implementation is correct, the next logical place to look is at your input.  What are you using as your 1k Hz signal source?

Tom,

I use sine (1 kHz, amplitude 0,2 V) on Vin+ input, and grounded Vin-

Hi Maria,

My apologies for not asking the question correctly, by your signal source, I was referring to the make/model of your signal generator.  What is the actual source of the 1k Hz, 0,2V sine wave?

To generate sine I use PXI-4461

OK - Thank you for confirming!

I'm not too familiar with the PXI-4461, do you know if you can route the analog output back to the analog input and perform an FFT on the raw signal?  I suspect your issue is more with the small signal level coming from the PXI-4416 than it is with the ADS1202 itself.