AnsweredAssumed Answered

internal FS calibration ad7794

Question asked by Kolik on Feb 1, 2012
Latest reply on Feb 21, 2012 by MaryMc

In the datasheet AD7794/AD7795 Rev.D is written "Internal full-scale calibrations cannot be performed when the gain equals 128."

Despite this I have included mode "Internal Full-Scale Calibration" and full scale registor for channel AN1+ AN1-, gain 128, REFIN1+ and REFIN1-  2.5 V,

the value has changed to 0x0054A700 0x006749E9.

Question - is the value of full scale registor used in analog digital convertion?

Thank you.


//---------------------- AD7794 register values following conversion -------------------------//


Config: 0000 0111 0001 1000



Burnout detect disabled

Bipolar coding

Boost off

Gain 128x

external 2.5V reference

Ref det enabled


Calibration pair 0 (for AN1+/AN1-)



Mode: 1010 0000 0000 1010 (internal full scale calibration)


Power switch open

Clock internal 64 kHz

Chop enabled

Update rate is 16.7Hz


Read FS registor