AnsweredAssumed Answered

AD7732 Extended Range to ±14 Volts?

Question asked by ecrean on Apr 10, 2014
Latest reply on May 12, 2014 by ChrisD.Rama

Looking at the AD7732 datasheet (page 31 – top diagram),  It looks to me like the ±10V comes from a voltage divider on each leg (108.5K in series with 15.5K to a common 2.5V reference). Hence a 0.125 divider per leg.  If we also connect the next leg (2R = 31K) to the reference, I think we increase the divider to allow for a ±14.375V input range. Am I missing something here? 

 

Vin (max)Input R (Series)Resistive Leg to Bias VoltageDividerADC Input
Bias RRA & RCRB & RDNet R
1010850015500 155000.1251.25
-1010850015500 155000.125-1.25
14.3751085001550031000 103330.0871.25
-14.3751085001550031000 103330.087-1.25
18.7510850015500310003100077500.0671.25
-18.7510850015500310003100077500.067-1.25


 

Thanks,

 

Ed

Outcomes