Patent attributes
A physical quantity measurement device includes a sensor element in which coupling capacitances are formed between a drive electrode and a first detection electrode and between the drive electrode and a second detection electrode; and a circuit device that includes a drive circuit which supplies a drive signal to the drive electrode, a detection circuit which detects physical quantity information corresponding to a physical quantity based on first and second detection signals from the first and second detection electrodes, and a failure diagnosis circuit. The circuit device includes first and second switches that are provided between first and second terminals to which the first and second detection signals are input and the detection circuit. The failure diagnosis circuit performs a failure diagnosis, based on a detection result of the detection circuit when connection states of the first and second switches are changed.