I need a circuit to monitor a DC voltage from 0 to 3 vdc. The voltage will slowly rise from 0 vdc and will stabilize in approximately 3 minutes. The stabilized voltage will be the calibration point of my circuit. Then I need the monitor to trigger an alarm if the voltage drops below a user adjustable set point. For instance: If my voltage stabilizes at 2.2 vdc, the calibration point becomes 2.2 vdc. Then I adjust a trigger point potentiometer to set the alarm trigger point to 10% below the calibration voltage. So in this case the alarm would sound when the monitored voltage drops to 1.98 vdc. Can this be done ?