Physical quantity detection circuit and physical quantity detection device

A physical quantity detection circuit, comprising:

• a drive circuit configured to apply a drive signal including a first frequency component for driving a physical quantity detection element to a drive electrode of the physical quantity detection element, the physical quantity detection element being configured to detect a physical quantity;
• a physical quantity detection signal output circuit configured to output a physical quantity detection signal corresponding to the physical quantity, based on a first physical quantity component included in a first signal output from a first detection electrode of the physical quantity detection element when the drive signal is applied to the physical quantity detection element and a second physical quantity component included in a second signal output from a second detection electrode of the physical quantity detection element when the drive signal is applied to the physical quantity detection element;
• and
• a first failure diagnosis signal output circuit,
• wherein the drive signal includes a second frequency component having a frequency different from a frequency of the first frequency component,
• the first signal includes a first electrostatic leakage component that is a component resulting from the second frequency component propagating to the first detection electrode via a first electrostatic coupling capacitor between the drive electrode and the first detection electrode,
• the second signal includes a second electrostatic leakage component that is a component resulting from the second frequency component propagating to the second detection electrode via a second electrostatic coupling capacitor between the drive electrode and the second detection electrode, and
• the first failure diagnosis signal output circuit is configured to output a first failure diagnosis signal generated based on the first electrostatic leakage component and the second electrostatic leakage component.