how to improve output accuracy

[rg.naveen]

Hi all

I have to buy an analog output card to simulate pressure sensors output signal to a UUT in the range of 0V - 50 mV. The customer requirement says that the simulating card must provide differential isolated output with 0.1mV accuracy and better resolution. So far after all comparisons I have landed in NI PXIe-4322 card. But this would partly match my requirement because the accuracy level is not matching my requirement.I tried to calculate the minimum accuracy that can be obtained using the example mentioned in datasheet and resulted in 1.12mV. So I need to get atlest 0.5mV accuracy. can this be solved using potential divider network in line and will it improve the accuracy. Have any one used this card or similar card and performed the experiment to imrove the accuracy.If yes what all parameters I have to take into consideration. Please anyone help me in resolving this.have any one used this card or similar card and 

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