The MAX1454 is typically used to amplify the signal from a Wheatstone bridge pressure sensor. A voltage can develop across the Wheatstone Bridge sensor when no pressure is applied to the sensors. This offset voltage can be removed using the Input-Referred Offset (IRO) DAC. The IRO DAC is used to correct sensor offset voltages prior to amplifying the voltage with a PGA. The sensor offset voltage can by measured directly across the sensor, or calculated using the equation below. Make sure to set IRO to a value of 0 for this calculation and apply what is considered to be 0 pressure for your system. PGA Input Voltage = Sensor Offset Voltage = (Vout-Vodac-Votcdac)/PGAgain The IRO DAC should be set to the opposite value calculated above, or the value measured across the sensor. Use Table 7 in the datasheet, presented below, to determine what register value is needed to obtain the proper offset correction.