How to reduce fluctuation / noise of analog input

[919370936119]

Dear Sir,

We are using Ni-PCIe-6320 card for reading excitated LVDT o/p (±5V - for 0.350mm travel) on analog i/p channel A0 wrt GND (Pin No. 68 & 67 of SCB-68). In stady condition we are getting fluctuation of 71 mV. We are using development platform of Microsoft Visual Studio 2008 (C#). In our application the permissible fluctuation is maximum 0.71 mV.

Please guide by which way we can reduce fluctuation upto acceptable limit. Is there any method (averaging) or any function by which we can acheive the result.

KVKulkarni

[Henrik_Volkers]

How does the analog signal look like?  (100+ms seen at max samplerate with alias filter, but please post as png 😉 ) Maybe with FFT

Some LVDT signal conditioner leave nasty spikes in the signal, groundloops are always good for humm, .... 

Powersupply of the LVDT?

Needed bandwidht ?

Exitationfrequence of the LVDT?

Spec of LVDT (you want 50nm, right)

Noise in the mV region is easely catched ... someone here in the board just found out that his graphic card was the reason....

Message Edited by Henrik Volkers on 11-02-2009 09:12 AM

[Kodeeswaran]

Hi,

   Try with the buffer circuit and do some average in the software, this will solve the problem,