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.