AD7795 REFIN+/-

Dear community, we inted to use AD7195 with AC excited strain gauge but in datasheet we have seen that pin REFIN+ must be in the range AVDD-AGND+1 and REFIN- in the range AGND to AVDD-1. If we use AC excitation pin REFIN+/- range from AVDD to AGND. Is this correct ?

  • 0
    •  Analog Employees 
    on Jun 12, 2012 12:52 PM

    Hello Mstv,

    The REF+ and REF- pins can go from GND to AVDD. The voltage REF+ to REF- must be between 1V and AVDD for dc excitation. However, the absolute voltage on the REF+ pin and the REF- pin can be GND and AVDD.

    With ac excitation, the reference voltage will be inverted during one phase of the excitation. The AD7195 can accomodate this inverted voltage also.

    Regards,

    Mary.