1 rating:

1 out of 5

Rate this Document

What Is the System Accuracy of the VXI-MIO-64E-1?

Hardware: VXI/VME/MXI>>VXI Data Acquisition and Instrument Modules>>VXI-MIO-64E-1

Problem: What is the system accuracy of the VXI-MIO-64E-1?

Solution: You can find the overall system accuracy by

square root(rel.accuracy^2 + gain error^2 + offset error^2 + system noise^2 + settling time acc.^2)

LSB (Least significant bits) = 10 V/4096 = 2.4 mV

Rel. accuracy = .5 LSB = 1.2 mV

Gain error = 0.02% of reading = .0002 * 10 V Full scale range = 2 mV

Offset error = pregain offset * gain + postgain offset 
             = .012 mV * gain + .5 mV 
             = .512 mV (gain = 1)
             =  1.7 mV (gain = 100)

Multiply System Noise times 3 to provide 3 standard deviations of the Gaussian error curve = 99% of total noise.

System noise = .15 LSB (Gain = .5-20) * 3 = 1.1 mV
             = .3 (gain = 50) * 3 = 2.2 mV
             = .5 (gain = 100) * 3 = 3.6 mV

Settling time accuracy depends on your sampling rate. Assume 0.5 LSB settling = 1.2 mV.

System accuracy (mV) 
= sqrt(1.2^2 + 2^2 + .512^2 + 1.1^2 + 1.2^2) = 
 2.9 mV = .029% (gain=1) = sqrt(1.2^2 + 2^2 +  1.7^2 + 3.6^2 + 1.2^2) = 
 4.8 mV = .048% (gn=100)


Related Links:   


Attachments:   







Report Date:   03/12/1997

Last Updated:   08/27/2003

Document ID:   0VB9QJSR






	     

                 

          
Your Feedback!
          
 Poor  |  Excellent 
         

          
 
          
Yes
          
No
		
        

          

            

               

                

                  

                     

                      
 Document Quality? 
					
				  
				
			  
			
		  
          

          

          

          

          

          

          

            

              

                

                  

                    

                      
 Answered Your Question? 
					
				  
				
			  
			
		  
          

          

		
        
 
          
1
          
2
          
3
          
4
          
5
        

          
Document needs work? Please tell us why.
          

          

            

              
Please Contact NI for all product and support inquiries.