Cirrus-logic AN330 REV2 Manual do Utilizador

Copyright  Cirrus Logic, Inc. 2009(All Rights Reserved)http://www.cirrus.comLoad Cell Measurement using the CS3001/02/11/12 Amplifiers with the CS551

10 AN330REV2AN330APPENDIX A. USING EXCEL® TO PRODUCE A NOISE HISTOGRAM PLOTTo use Excel® spreadsheet software to produce a noise histogram plot, one m

AN330REV2 11AN330An example which uses the 256 samples from the CS3001-CS5513 circuit yields the following result:One can then use the Chart Wizard in

12 AN330REV2AN3305. REVISION HISTORYRelease Date ChangesREV1 Oct 2008 Initial ReleaseREV2 Apr 2009 Minor typographical error corrected on page 5.Conta

2 AN330REV2AN330of the codes ( [(2.04 / 8) • 1048576] = 267387 ) of the converter as the load on the load cell goes from zero to fullscale. But how m

AN330REV2 3AN330Figure 3. In this case, the effective noise bandwidth of the digital filter would be that of the Sinc3 filter. This is 0.275 times th

4 AN330REV2AN330The noise contributed by the ADC is distributed across the spectrum up to one-half the converter output word rate.The sample rate of t

AN330REV2 5AN330deviation was calculated with a result equal to 1.8 codes. The amount of voltage represented by one code of theconverter would be the

6 AN330REV2AN3303. CS3001 AND CS5512 COMBINATION CIRCUIT WITH BRIDGE OFFSETThe second circuit is similar to the first. It uses a single CS3001 amplifi

AN330REV2 7AN3307X√5 = 15.7 nVrms. The peak-to-peak noise would be 6.6 (±3.3 standard deviations) times 15.7 nV or 103.6 nVpp. Therefore, the resultin

8 AN330REV2AN3304. CS3002 AND CS5512 COMBINATION CIRCUIT WITH BRIDGE OFFSETWith two op amps the noise due to the amplifiers will increase by a factor

AN330REV2 9AN330If 32 output words were averaged, the effective output would yield results at 326 Sps / 32 = 10.18 Sps with an ef-fective noise bandwi