Liquid occlusion ejection from a pressure sensor cavity with pulsed liquid heating

An electronic device, comprising:

• a housing having an opening;
• a particulate protection element disposed within the opening;
• a pressure sensor disposed within a cavity adjacent to the opening and exposed to an environment external to the housing via the opening;
• a heating element disposed within the cavity;
• and
• processing circuitry configured to:
• expel a water film that forms on one or more apertures of the particulate protection element by causing the heating element to form a gas pocket around the heating element inside a cavity of the pressure sensor using a first power pulse during a first phase and further causing the heating element to expand the gas pocket around the heating element using a second power pulse during a second phase.

A smart watch, comprising:

• a housing having an opening;
• a pressure sensor disposed within a cavity adjacent to the housing and exposed to an environment external to the housing via the opening;
• processing circuitry configured to:
• obtain pressure sensor data from the pressure sensor,
• determine that the opening is occluded based at least in part on a change in pressure within the cavity,
• apply a first power pulse during a first phase, and
• apply a second power pulse during a second phase following the first phase;
• and
• a heating element associated with the pressure sensor and disposed within the cavity, the heating element configured to:
• heat at least a portion of a water volume inside the cavity during the first phase based on the first power pulse to cause a gas pocket to form around the heating element;
• and
• displace at least a portion of the water volume inside the cavity by causing the gas pocket to expand around the heating element during the second phase based on the second power pulse.