the REF IN/REF OUT pin of AD7091r_2 output a voltage which is 6.0V,but the refered voltage is 4.096V provided by REF198 ?

I am using AD7091r_2,  using REF198 as  thethe refered  voltage,which is   4.096V ,    and  the input voltage of  Vin0  and Vin1  of the AD7091r_2 is from 0 to 6V ,   when the input of Vin0  is 6V  and the input of Vin1 is 0V,  the REF IN/REF OUT pin of AD7091r_2  become 6V . When  the REF IN/REF OUT pin of AD7091r_2 is disconnected , the REF IN/REF OUT pin is still  6.0V  when the input of Vin0  is 6V  and the input of Vin1 is 0V,  what is happening ?

or the input of the Vin0  and Vin1 must be controled beside the   refered  voltage 4.096V ?



add description of the REF IN/REF OUT pin of AD7091r_2
[edited by: microchip_zh at 10:02 PM (GMT 0) on 10 Jun 2020]
  • 0
    •  Analog Employees 
    on May 3, 2021 4:54 AM

    Hi, 

    Apologies for missing this item. But first if you are using a reference voltage of 4.096V then the analog input voltage range must also be up to 4.096V only. If you provided a voltage beyond this then the result will be full scale. One thing to note is the abs max rating is up to Vref + 0.3V only so if you provided an input voltage up to 6V the part can be damaged. So please ensure that your inputs are always within specification. 

    Thanks,

    Jellenie