Abstract:
A thermostat includes a plurality of HVAC (heating, ventilation, and air conditioning) wire connectors for receiving a plurality of HVAC control wires corresponding to an HVAC system. The thermostat also includes a thermostat processing and control circuit configured to at least partially control the operation of the HVAC system and a powering circuit coupled to the HVAC wire connectors and configured to provide an electrical load power to the thermostat processing and control circuit. The powering circuit has a power extraction circuit configured to extract electrical power from one or more of the plurality of received HVAC control wires up to a first level of electrical power, a rechargeable battery, and a power control circuit coupled to the power extraction circuit, the rechargeable battery, and the thermostat processing and control circuit. The power control circuit is configured to provide the electrical load power using power from the power extraction circuit and the rechargeable battery.
Abstract:
A thermostat includes a user interface that is configured to operate in at least two different modes including a first mode and a second mode. The user interface may require more power when operating in the first mode than in the second mode. The thermostat also includes a plurality of sensors, including at least one sensor configured to detect a presence of a user within a proximity of the thermostat. The thermostat additionally includes a first processing function that is configured to determine a proximity profile and to cause the user interface to be in the first mode one or more sensors provides responses that match the proximity profile. The proximity profile may be computed using a history of responses from the sensors that are likely to coincide with times where users intend to view the user interface.
Abstract:
In a multi-sensing, wirelessly communicating learning thermostat that uses power-harvesting to charge an internal battery, methods are disclosed for ensuring that the battery does not become depleted or damaged while at the same time ensuring selected levels of thermostat functionality. Battery charge status is monitored to determine whether the present rate of power usage needs to be stemmed. If the present rate of power usage needs to be stemmed, then a progression of performance levels and/or functionalities are scaled back according to a predetermined progressive power conservation algorithm. In a less preferred embodiment, there is a simple progressive shutdown of functionalities turned off in sequence until the desired amount of discharge stemming is reached. Battery charge preservation measures are also described for cases when an interruption of external supply power used to recharge the battery is detected.