Patent ID: 7870858

Claim:
A ventilator ( 20 ) adapted to deliver a flow of gas to an airway of a patient, wherein the ventilator includes a sensor provided to monitor characteristic associated with the delivery of gas to the patient and a sensor configuration ( 100 , 130 ) to provide power to the sensor, characterized in that: the sensor configuration includes a Wheatstone bridge ( 102 ) having a first end ( 104 ), a second end ( 106 ), a first leg ( 108 ) extending between the first end and the second end, and a second leg ( 110 ) extending between the first end and the second end in parallel with the first leg; the first end is coupled to a first positive voltage source ( 112 , 142 ), a capacitor ( 120 ) having a first end is coupled to the second end of the Wheatstone bridge; a second positive voltage source ( 118 , 156 , 180 ) is coupled to a second end of the capacitor; and a controller ( 50 ) controls the first and the second positive voltage sources so as to (a) disable the sensor by causing the first positive voltage source to provide substantially zero voltage to the first end of the Wheatstone bridge and by causing the second positive voltage source to provide a positive voltage to the second end of the capacitor, and to (b) enable the sensor by causing the first positive voltage source to provide a positive voltage to the first end of the Wheatstone bridge and by causing the second positive voltage source to provide a decreasing voltage to the second end of the capacitor.