Abstract: Hazard detection systems according to embodiments described herein are operative to provide failsafe safety detection features and user interface features using circuit topology and power budgeting methods that minimize power consumption. The safety detection features can monitor environmental conditions (e.g., smoke, heat, humidity, carbon monoxide, carbon dioxide, radon, and other noxious gasses) in the vicinity of the hazard detection system associated and alarm occupants when an environmental condition exceeds a predetermined threshold.

Abstract: Apparatus, systems, methods, and related computer program products for handling temperature variation with optoelectronic components of a hazard detection system are described herein. A power characteristic of an optoelectronic component of the hazard detection system may be used to determine a temperature of an environment of the hazard detection system. A power characteristic of an optoelectronic component of the hazard detection system may be used to determine a smoke condition of an environment of the hazard detection system. Optoelectronic components of the hazard detection system may be optically coupled to determine a smoke condition of an environment of the hazard detection system. Multiple optoelectronics of the hazard detection system may be operative to detect forward scatter and back scatter of one or more types of light to determine a characteristic of a hazard particle.

Abstract: Apparatus, systems, methods, and related computer program products for handling temperature variation with optoelectronic components of a hazard detection system are described herein. A power characteristic of an optoelectronic component of the hazard detection system may be used to determine a temperature of an environment of the hazard detection system. A power characteristic of an optoelectronic component of the hazard detection system may be used to determine a smoke condition of an environment of the hazard detection system. Optoelectronic components of the hazard detection system may be optically coupled to determine a smoke condition of an environment of the hazard detection system. Multiple optoelectronics of the hazard detection system may be operative to detect forward scatter and back scatter of one or more types of light to determine a characteristic of a hazard particle.

Abstract: Apparatus, systems, methods, and related computer program products for handling temperature variation with optoelectronic components of a hazard detection system are described herein. A power characteristic of an optoelectronic component of the hazard detection system may be used to determine a temperature of an environment of the hazard detection system. A power characteristic of an optoelectronic component of the hazard detection system may be used determine a smoke condition of an environment of the hazard detection system. Optoelectronic components of the hazard detection system may be optically coupled to determine a smoke condition of an environment of the hazard detection system. Multiple optoelectronics of the hazard detection system may be operative to detect forward scatter and back scatter of one or more types of light to determine a characteristic of a hazard particle.

Abstract: Systems for ensuring an audible alarm circuit sounds at a minimum magnitude of loudness are provided. Different circuitry embodiments discussed herein are each capable of assisting the audible alarm circuit in maintaining a minimum loudness threshold. Audible alarm circuit operation optimization can be achieved using embodiments that fall within anyone of four general categories: compensation networks, direct drive, dynamic tuning, and microphone feedback based dynamic tuning. Use of such circuitry can increase production yields by compensating for manufacturing variations of alarm components and aging characteristics of the components.

Abstract: Apparatus, systems, methods, and related computer program products for handling temperature variation with optoelectronic components of a hazard detection system are described herein. A power characteristic of an optoelectronic component of the hazard detection system may be used to determine a temperature of an environment of the hazard detection system. A power characteristic of an optoelectronic component of the hazard detection system may be used to determine a smoke condition of an environment of the hazard detection system. Optoelectronic components of the hazard detection system may be optically coupled to determine a smoke condition of an environment of the hazard detection system. Multiple optoelectronics of the hazard detection system may be operative to detect forward scatter and back scatter of one or more types of light to determine a characteristic of a hazard particle.

Abstract: Systems and methods for driving optical sources operating at different wavelengths within a smoke sensor are described herein. Multiple optical sources such as light emitting diodes may be used in a photoelectric smoke sensor to detect particles of different sizes. Photoelectric smoke sensors can operate by pulsing the LEDs and measuring a response in a light sensor. The signal measured at the light sensor changes based on the quantity of particles existing in a smoke chamber. Each optical source may have different operational characteristics and thus require different drive currents to operate. LED driving circuitry according to embodiments discussed herein provide a consistent and reliable drive current to each optical source, while maximizing efficiency of power consumption across a range of possible voltages provided by different power sources.

Abstract: Hazard detection systems according to embodiments described herein are operative to provide failsafe safety detection features and user interface features using circuit topology and power budgeting methods that minimize power consumption. The safety detection features can monitor environmental conditions (e.g., smoke, heat, humidity, carbon monoxide, carbon dioxide, radon, and other noxious gasses) in the vicinity of the hazard detection system associated and alarm occupants when an environmental condition exceeds a predetermined threshold.

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 operative 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 thermostat includes circuitry and methods for maximizing efficiency of energy harvested from the HVAC system connected to the thermostat, and depending on which system is connected to the thermostat, different power schemes can be implemented in order to obtain power from the HVAC system.

Abstract: Systems and methods for driving optical sources operating at different wavelengths within a smoke sensor are described herein. Multiple optical sources such as light emitting diodes may be used in a photoelectric smoke sensor to detect particles of different sizes. Photoelectric smoke sensors can operate by pulsing the LEDs and measuring a response in a light sensor. The signal measured at the light sensor changes based on the quantity of particles existing in a smoke chamber. Each optical source may have different operational characteristics and thus require different drive currents to operate. LED driving circuitry according to embodiments discussed herein provide a consistent and reliable drive current to each optical source, while maximizing efficiency of power consumption across a range of possible voltages provided by different power sources.

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 operative 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 thermostat includes circuitry and methods for maximizing efficiency of energy harvested from the HVAC system connected to the thermostat, and depending on which system is connected to the thermostat, different power schemes can be implemented in order to obtain power from the HVAC system.

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. 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 method of harvesting power from a heating, ventilation, and air conditioning (HVAC) system using an HVAC controller may include harvesting power from the HVAC system and measuring an electrical characteristic of the HVAC controller. The electrical characteristic may indicate whether the power harvested from the HVAC system is high enough to risk interfering with a normal operation of the HVAC system. The method may also include increasing the power harvested from the HVAC system until the electrical characteristic indicates that the HVAC controller is at risk of interfering with the normal operation of the HVAC system.

Abstract: A thermostat is described that includes a rechargeable battery, a graphical user interface and a wireless network communication capabilities. During installation, in cases where the rechargeable battery is below a first threshold, the installation procedure is limited so as to avoid energy intensive installation steps which may not be supported by the low battery level. An example of an installation step that is avoided due to low battery level is set up of wireless communication. According to some embodiments, if the battery level is very low during initial installation, the installation process is halted while the battery is charged. An indication such as a flashing LED may be displayed so as to indicate to the user that the battery is being charged.

Abstract: A thermostat is described that includes a rechargeable battery, a graphical user interface and a wireless network communication capabilities. During installation, in cases where the rechargeable battery is below a first threshold, the installation procedure is limited so as to avoid energy intensive installation steps which may not be supported by the low battery level. An example of an installation step that is avoided due to low battery level is set up of wireless communication. According to some embodiments, if the battery level is very low during initial installation, the installation process is halted while the battery is charged. An indication such as a flashing LED may be displayed so as to indicate to the user that the battery is being charged.

Abstract: A thermostat for controlling an HVAC system in an enclosure may include a passive infrared sensor, an active infrared sensor, and an electronic display having a first mode and a second mode. The thermostat may also include one or more processors programmed to change a setpoint temperature of the thermostat to an energy-saving temperature upon detection of a non-occupancy condition for the enclosure. The processor(s) may detect the non-occupancy condition based at least in part on readings received from the passive infrared sensor. The processor(s) may also be programmed to change the electronic display from the first mode to the second mode upon detection of a person approaching the thermostat. The processor(s) may detect a person approaching the thermostat based at least in part on readings received from the active infrared sensor.

Abstract: An electronic thermostat and associated methods are disclosed for power stealing from an HVAC triggering circuit. The methods include making voltage measurements while controlling the amount of current drawn by the power stealing circuitry so as to determine a relationship that can be used to select how much current to draw during power stealing. Through the use of the described methods, the likelihood of inadvertent switching of the HVAC function (on or off) can be significantly reduced.

Abstract: A screen protector is provided with tactile aids for vision-impaired users. The screen protector can be placed on the display screen of a computing device to enhance the out-of-box experience for vision-impaired users and/or guide the user during subsequent use of the device. For example, the screen protector can be configured to be tactilely-informative about how to activate accessibility features of the device and/or how to proceed with initial set-up and configuration of the device. The screen protector may include, for example, braille instructions for activating the accessibility mode and/or a raised or embossed tactile aid that identifies the location of a UI control feature that can be engaged to initiate the accessibility mode or other desired function. Once the user has engaged the accessibility mode, the user may receive verbal instructions and cues going forward so as to allow the user to successfully use the device.

Abstract: Hazard detection systems according to embodiments described herein are operative to provide failsafe safety detection features and user interface features using circuit topology and power budgeting methods that minimize power consumption. The safety detection features can monitor environmental conditions (e.g., smoke, heat, humidity, carbon monoxide, carbon dioxide, radon, and other noxious gasses) in the vicinity of the hazard detection system associated and alarm occupants when an environmental condition exceeds a predetermined threshold.

Abstract: A user-friendly, network-connected learning thermostat is described. The thermostat is made up of (1) a wall-mountable backplate that includes a low-power consuming microcontroller used for activities such as polling sensors and switching on and off the HVAC functions, and (2) separable head unit that includes a higher-power consuming microprocessor, color LCD backlit display, user input devices, and wireless communications modules. The thermostat also includes a rechargeable battery and power-stealing circuitry adapted to harvest power from HVAC triggering circuits. By maintaining the microprocessor in a “sleep” state often compared to the lower-power microcontroller, high-power consuming activities, such as learning computations, wireless network communications and interfacing with a user, can be temporarily performed by the microprocessor even though the activities use energy at a greater rate than is available from the power stealing circuitry.