Patent Publication Number: US-10334699-B2

Title: Multi-mode control device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 14/535,912, filed on Nov. 7, 2014, entitled “Multi-Mode Control Device,” which claims priority to U.S. Provisional Application Ser. No. 61/901,600 filed Nov. 8, 2013 and titled “Dual Power Mode System,” the contents of which are hereby incorporated by reference. 
     U.S. patent application Ser. No. 14/539,929, entitled “Multi-Mode Control Device,” which was filed on Nov. 7, 2014, is incorporated by reference herein in its entirety. 
    
    
     FIELD OF THE INVENTION 
     This disclosure relates generally to control devices and more particularly relates to control devices having multiple power modes. 
     BACKGROUND 
     In lighting systems and other electrical systems, control devices can be used to control operations of lighting devices and other load devices. For example, a control device can be communicatively coupled to a load device. The control device can transmit control signals to the load device (or a load controller associated with the load device) that can cause the load device to change state (e.g., turn on, turn off, increase illumination, decrease illumination). 
     In prior solutions, a control device may be electrically coupled to a power source that is used to power the load device in such a manner that causing a reduction in the power provided to the load device also removes power from the control device. These prior solutions can prevent the control device from performing monitoring functions or other operations related to the load device when the load device is powered off. 
     SUMMARY 
     In some aspects, a multi-mode control device is provided for controlling one or more operations of a load device (e.g., a load device external to the control device, a load device included in the control device, etc.). The control device includes a high-power interface, a low-power interface, and a control module. The high-power interface can be electrically coupled to a high-power module providing current from an external power source to the load device. The low-power interface can be electrically coupled to a low-power module. The high-power interface can receive a first current from the high-power module. The low-power interface can receive a second current from the low-power module that is less than the first current. The low-power interface can prevent the first current from flowing to the low-power module. The control module, which is electrically coupled to the high-power interface and the low-power interface, be powered by one or more of the first and second current. 
     These and other aspects, features and advantages of the present invention may be more clearly understood and appreciated from a review of the following detailed description and by reference to the appended drawings and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram illustrating an example of an electrical system in which a multi-mode control device can control a load device using a separate load controller according to some aspects. 
         FIG. 2  is a block diagram illustrating an example of an electrical system in which a multi-mode control device is positioned in an electrical path between a power source and a load device for controlling operation of the load device according to some aspects. 
         FIG. 3  is a block diagram illustrating an example of the multi-mode control device of  FIG. 1 or 2  using leakage current to ground as a power source for a low-power mode according to some aspects. 
         FIG. 4  is a block diagram illustrating an example of the multi-mode control device of  FIG. 1 or 2  using one or more of an energy storage device and an energy harvesting device as a power source for a low-power mode according to some aspects. 
         FIG. 5  is a block diagram illustrating an example of the multi-mode control device of  FIG. 1 or 2  in which power routing circuitry includes parallel electrical circuitry for powering low-power circuitry and high-power circuitry according to some aspects. 
         FIG. 6  is a partial block diagram illustrating an alternative example of the multi-mode control device of  FIG. 1 or 2  in which power routing circuitry includes multiple diodes for providing power to low-power circuitry and high-power circuitry in different power modes according to some aspects. 
         FIG. 7  is a partial block diagram illustrating an alternative example of the multi-mode control device of  FIG. 1 or 2  in which power routing circuitry includes a transistor or other switching component that is used for providing power to low-power circuitry based on a reading from sensing circuitry according to some aspects. 
         FIG. 8  is a partial block diagram illustrating an alternative example of the multi-mode control device of  FIG. 1 or 2  in which an energy storage device for providing power to low-power circuitry is configured to store energy when the multi-mode control device is in a high-power mode according to some aspects. 
         FIG. 9  is a partial block diagram illustrating an alternative example of the multi-mode control device of  FIG. 1 or 2  that includes high-power sensing circuitry and a trigger detection device according to some aspects. 
         FIG. 10  is a partial block diagram illustrating an alternative example of the multi-mode control device of  FIG. 1 or 2  that includes high-power sensing circuitry and a trigger detection device, where an energy storage device for providing power to low-power circuitry is configured to store energy when the multi-mode control device is in a high-power mode according to some aspects. 
         FIG. 11  is a flow chart depicting an example of a process using a multi-mode control device to implement a power control scheme using a combination of high-power sensing circuitry and a low-power trigger detection device according to some aspects. 
         FIG. 12  is a flow chart depicting an example of a process using a multi-mode control device to implement a power control scheme involving an interim power mode using a combination of high-power sensing circuitry and a low-power trigger detection device according to some aspects. 
         FIG. 13  is a flow chart depicting an example of a process for operating a multi-mode control device using a combination of manual inputs and information received from an occupancy sensor according to some aspects. 
         FIG. 14  is a flow chart depicting an example of a process for operating a multi-mode control device using a combination of manual inputs and information received from a light sensor according to some aspects. 
         FIG. 15  is a flow chart depicting an example of a process for operating a multi-mode control device using a combination of manual inputs, sensor information received from an occupancy sensor, and control messages from a remote control device according to some aspects. 
         FIG. 16  is a flow chart depicting an example of a process for operating a multi-mode control device using a combination of manual inputs, information from sensors, and voltage detection at the load device according to some aspects. 
     
    
    
     DETAILED DESCRIPTION 
     Aspects of the present invention provide a multi-mode control device, also referred to herein as a control device. The multi-mode control device can control one or more operations of a load device that is communicatively coupled to the control device (e.g., via a wire that can be used to transmit a low-voltage control signal from the control device to the load device). A non-limiting example of such a control device is a lighting controller that controls the state of a lighting device (i.e. the load device). The multi-mode control device can have at least two power modes. A first power mode of the control device can correspond to the load device being energized (i.e., the load being in an “ON” state). In the first power mode, some or all components of the control device can be powered using current that is harvested or otherwise obtained from current flowing to the load device via suitable conductor (e.g., a power wire). A second power mode of the control device can correspond to the load device not being energized (i.e., the load being in an “OFF” state). In the second power mode, at least some components of the control device are powered using an alternate power source that provides lower power than would be available from the current flowing to an energized load device. Examples of an alternate source include (but are not limited to) leakage current to earth ground, a battery or other energy storage device, an energy harvesting device, etc. 
     In some aspects, the multi-mode control device can include a high-power interface, a low-power interface, and a control module. The high-power interface can be electrically coupled to a high-power module that provides current from an external power source to the load device. The high-power interface can receive current from the high-power module. For example, the high-power module may include one or more connections to an electrical path between the power source and the load device. The high-power module can be used to power the control device in a high-power mode. The low-power interface can be electrically coupled to a low-power module. Examples of a low-power module include connections to earth ground, a battery or other energy storage device, an energy harvesting device, etc. The low-power interface can receive current from the low-power module. The current received via the low-power interface can be less than the current received via the high-power interface. The low-power interface can prevent at least some current received via the high-power interface from flowing toward the low-power module. The control module can be electrically coupled to the high-power interface and the low-power interface. 
     In some aspects, an electrical coupling can involve a direct connection, such as a wire or other electrical conductor being used as a current path between the control device and the high-power module and/or between the control device and the low-power module. In other aspects, an electrical coupling can involve a wireless connection, such as an inductive transfer of current between the control device and the high-power module and/or between the control device and the low-power module. 
     The control device can operate in a high-power mode in which at least some devices in the control module (e.g., a microprocessor or other processing device, a radio transceiver or other communication device, etc.) are powered by the current received via the high-power interface. The control device can also operate in a low-power mode in which at least one device in the control module is powered by the current received via the low-power interface. For example, in the low-power mode, a processing device in the control module may be continuously powered by the current received via the low-power interface, and a communication device in the control module may either be unpowered or be intermittently powered by the current received via the low-power interface. 
     These illustrative examples are given to introduce the general subject matter discussed herein and are not intended to limit the scope of the disclosed concepts. The following sections describe various additional aspects and examples with reference to the drawings in which like numerals indicate like elements. 
     The features discussed herein are not limited to any particular hardware architecture or configuration. A computing device can include any suitable arrangement of components that provide a result conditioned on one or more inputs. Suitable computing devices include multipurpose microprocessor-based computer systems accessing stored software that programs or configures the computing system from a general-purpose computing apparatus to a specialized computing apparatus implementing one or more aspects of the present subject matter. Any suitable programming, scripting, or other type of language or combinations of languages may be used to implement the teachings contained herein in software to be used in programming or configuring a computing device. 
       FIG. 1  is a block diagram illustrating an example of a multi-mode control device  102  that can control operation of a load device  116  using a separate load controller  115  in an electrical system  100 . The multi-mode control device  102  can be used to control one or more operations of a load device  116 . 
     A non-limiting example of a multi-mode control device  102  is a lighting controller that controls the state of a lighting device (i.e., a load device  116 ). In some aspects, such a lighting controller can provide manual-on/occupancy-off lighting control using a remote wireless occupancy sensor. The manual-on/occupancy-off lighting control can allow a user to manually activate a switch or button to turn a lighting device on or off. When the lighting device is turned on, the occupancy sensor can determine whether an area corresponding to the lighting device is occupied. If the sensor detects that the area is no longer occupied, the lighting controller can turn off the lighting device. 
     In some aspects, the multi-mode control device  102  can control a load controller  115 , and the load controller  115  can control the operation of a load device  116 , as depicted in  FIG. 1 . In additional or alternative aspects, the load controller  115  can include one or more components in the multi-mode control device  102  such that the load controller  115  is wholly or partially integrated into the multi-mode control device  102 . 
     The multi-mode control device  102  can be operated in two or more power modes, such as (but not limited to) a high-power mode and a low-power mode. The high-power mode can involve the multi-mode control device  102  using more power than the amount of power used by the multi-mode control device  102  in the low-power mode. In some aspects, both the high-power mode and the low-power mode can involve the control device  102  using less power than other devices in the electrical system  100 , such as the load controller  115  or the load device  116 . 
     The multi-mode control device  102  depicted in  FIG. 1  includes power routing circuitry  103  and a control module  106 . The power routing circuitry  103  can include a low-power interface  104  and a high-power interface  105 . The control module  106  can include components that require power, such as a radio or other communication device, a microcontroller or other processing device, one or more load control components, one or more button interface components, one or more load voltage or load current sensing components, etc. 
     The low-power interface  104  can include one or more components that are used to route power that is received via a low-power module  112  to the control module  106  when the multi-mode control device  102  is in a low-power mode. In some aspects, the low-power module  112  can include a separate power source (e.g., a battery or other energy storage device). In additional or alternative aspects, the low-power module  112  can include one or more components for powering the multi-mode control device  102  using a lower current from a power source powering the load device than the current obtained from an electrical connection between the load device  116  and the power source via the high-power module  114 . For example, the low-power module can include circuitry or other components for passing current from the power source through earth ground. 
     The high-power interface  105  can include one or more components that are used to route power that is received via a high-power module  114  to the control module  106  when the multi-mode control device  102  is in a high-power mode. The high-power module  114  can include one or more components used for harvesting or otherwise obtaining power from current used to drive the load device  116 . For example, the high-power module  114  can include one or more components that can electrically couple the multi-mode control device  102  to a line voltage or other electrical connection between a power source and the load device  116  or the load controller  115 . 
     The low-power module  112  and high-power module  114  may be assembled using standard components. One or both of the low-power module  112  and the high-power module  114  may be designed or otherwise configured such that power supplied to the load via the high-power module  114  is not significantly affected by the power used by the multi-mode control device  102  when the load device  116  is powered. For example, the low-power module  112  may be designed or otherwise configured to pass current through earth ground. The low-power module  112  may be current limited such that no more than 500 uA is passed through earth ground. 
     The control module  106  can include high-power circuitry  108  that is powered using current that is obtained using the high-power module  114 . The control module  106  can also include low-power circuitry  110  that is powered using current that is obtained using the low-power module  112 . In some aspects, the low-power circuitry  110  can be a subset of the high-power circuitry, as depicted in  FIG. 1 . For example, the high-power circuitry  108  can include a microprocessor, a radio transceiver, and a relay, and the low-power circuitry  110  can include the microprocessor, but not the radio transceiver or the relay. In additional or alternative aspects, the high-power circuitry  108  and the low-power circuitry  110  can include non-overlapping sets of devices. 
     In some aspects, a high-power mode of the multi-mode control device  102  can correspond to the load device  116  being energized (e.g., the load device being in an “ON” state). A low-power mode can correspond to the load device  116  not being energized (e.g., the load being in an “OFF” state). In the high-power mode, some or all components of the multi-mode control device  102  can be powered using current that flows through the load device  116 . In the low-power mode, at least some components of the control device can be powered using an alternate source (such as, but not limited to, leakage current to earth ground, a battery, etc.). 
     Although  FIG. 1  depicts the multi-mode control device  102  controlling one or more operations of a load device  116  using a separate load controller  115 , other implementations are possible. For example,  FIG. 2  is a block diagram illustrating an alternative example of an electrical system  100  in which the multi-mode control device  102  is positioned in an electrical path between a high-power module  114  or other power source and the load device  116 . The control device  102  depicted in  FIG. 2  can include one or more switching components that can selectively couple the high-power module  114  to the load device  116 . 
     In some aspects, the multi-mode control device  102  can be powered using leakage current.  FIG. 3  is a block diagram illustrating an example of the multi-mode control device  102  using leakage current to ground as a power source for a low-power mode. The implementation depicted in  FIG. 3  can be used in environments in which a neutral wire is not present in an electrical box used to power one or more load devices. For example, a power box may include connections to a power wire, a load wire, and earth ground. Some regulatory agencies may limit the amount of current that can be passed through earth ground (e.g., to 500 uA). The implementation depicted in  FIG. 3  can use the low amount of current passed to earth ground for powering low-power circuitry  110  in a low-power mode. 
     As depicted in  FIG. 3 , the high-power module  114  can include electrical connections to a power source  202 . The power source  202  can provide current to the load device  116  via the load controller  115  (or, in some aspects, directly to the load device  116 ). Current can be provided from the power source via a wire  204  or other suitable conductor. Current can be returned to the power source via a wire  206  or other suitable conductor. In some aspects (as depicted in  FIG. 3 ), a wire  204  can be used to provide current to the load device  116  (either directly or via a load controller  115 ) and current return can be provided via a neutral wire, such as the wire  206 . The high-power module  114  can include an electrical coupling  208  between the high-power interface  105  and wire  204  and an electrical coupling  210  between the high-power interface  105  and wire  206 . Current can be provided to the high-power interface  105  of the multi-mode control device  102  via the electrical coupling  208 . Current can be returned from the high-power interface  105  via the electrical coupling  210 . In some aspects, one or more of the electrical couplings  208 ,  210  can be direct connections (e.g., via wires or other conductors). In additional or alternative aspects, one or more of the electrical couplings  208 ,  210  can be inductive couplings (e.g., via a transformer). 
     As depicted in  FIG. 3 , the low-power module  112  can include current limiting circuitry  212  and a connection  213  to earth ground. The current limiting circuitry  212  can include one or more components (such as, but not limited to, transformers) for reducing an amount of current from the power source  202  that is leaked to earth ground. The reduced amount of current is provided to the multi-mode control device  102  via the low-power interface  104 . The current is leaked to earth ground via an electrical connection between low-power interface  104  and the connection  213  to earth ground. 
     In additional or alternative aspects, the multi-mode control device  102  can be powered using one or more of an energy storage device and an energy harvesting device.  FIG. 4  is a block diagram illustrating an example of the multi-mode control device  102  using an energy storage device  214  as a power source for a low-power mode. Non-limiting examples of an energy storage device  214  include a replaceable battery, a rechargeable battery, a capacitor, etc. The multi-mode control device  102  can be powered by the energy storage device  214  via the low-power interface  104 . 
     In some aspects, an energy harvesting device  216  can be electrically coupled to the energy storage device  214 , as depicted in  FIG. 4 . Non-limiting examples of an energy harvesting device  216  include a light harvesting device, a device configured to convert kinetic energy into electrical energy, etc. 
     Although  FIG. 4  depicts an implementation in which both an energy storage device  214  and an energy harvesting device  216  are used to power the multi-mode control device  102 , other implementations are possible. For example, in some aspects, the energy storage device  214  may be omitted and the energy harvesting device  216  can be directly coupled to the low-power interface  104 . In other aspects, the energy harvesting device  216  may be omitted and the energy storage device  214  can be used to power the multi-mode control device  102  via the low-power interface  104 . 
     In some aspects, the low-power interface  104  and high-power interface  105  can include electrically isolated circuitry that powers the low-power circuitry  110  and the high-power circuitry  108 . For example,  FIG. 5  is a block diagram illustrating an example of the multi-mode control device  102  in which the power routing circuitry  103  includes parallel electrical circuitry  300 ,  301  for powering the low-power circuitry  110  and the high-power circuitry  108 . 
     In the example depicted in  FIG. 5 , the high-power circuitry  108  includes a communication device  304 , and switching circuitry  306  (e.g., a relay), and the low-power circuitry  110  includes a processing device  302 . In the high-power mode, both the high-power circuitry  108  and the low-power circuitry  110  can be powered. In the low-power mode, the low-power circuitry  110  can be powered and the high-power circuitry can be unpowered. For example, current can be provided to the processing device  302  via the circuitry  300  that is electrically connected to the low-power module  112 . For example, the low-power module  112  can be used to power the processing device  302  using leakage current to earth ground, as depicted in  FIG. 3  above. Current can be provided to the communication device  304  and the switching circuitry  306  via the circuitry  301  that is electrically connected to the high-power module  114 . For example, the high-power module  114  can be used to power the communication device  304  and the switching circuitry  306  using current that is harvested or otherwise obtained from power that is provided from the power source  202  to one or more load devices via the high-power module  114 , as described above with respect to  FIGS. 4 and 5 . The circuitry  300 ,  301  can be electrically isolated from one another. 
     The processing device  302  can include any suitable device or group of devices configured to execute code stored on a computer-readable medium. Examples of processing device  302  include a microprocessor, a mixed signal microcontroller, an application-specific integrated circuit (“ASIC”), a field-programmable gate array (“FPGA”), or another suitable processing device. 
     The communication device  304  can include a device that is configured to communicate signals via a wired or wireless communication link. Examples of the communication device  304  include a radio transceiver, a radio transmitter, a radio receiver, etc. In some aspects, the communication device  304  may communicate with remote sensors (not depicted) such as (but not limited to) a wireless occupancy sensor, a light sensor, etc. 
     The switching circuitry  306  can include one or more components that can be used by the multi-mode control device  102  for changing the state of a load controller  115  or a load device  116 . For illustrative purposes,  FIG. 5  and other figures depict switching circuitry  306  as being included in the multi-mode control device  102 . For example, the switching circuitry  306  may include a relay that does not require power when the load device  116  is not energized and that is integrated with the multi-mode control device  102 . However, other implementations are possible. For example, the switching circuitry  306  may include one or more components of a load controller  115  that are external to the multi-mode control device  102 , as depicted in  FIG. 1 . 
       FIG. 6  is a partial block diagram illustrating an alternative example of the multi-mode control device  102  in which the power routing circuitry  103  includes multiple diodes  402 ,  404  for providing power to high-power circuitry  108  and the low-power circuitry  110 . The low-power interface  104  can include the diode  402 . The high-power interface  105  can include the diode  404 . In some aspects, the high-power interface  105  can include one or more electrical connections to high-power circuitry  108  that is not powered in the low-powered mode, such as (but not limited to) switching circuitry  306 . The electrical connections to high-power circuitry  108  that is not powered in the low-powered mode can be connected to a circuit path between the high-power module  114  and an anode of the diode  402 . 
     An output of the low-power module  112  can be electrically coupled to the anode of a diode  402 . An input of the processing device  302  or other low-power circuitry  110  can be electrically coupled to the cathode of the diode  402 . The diode  402  can prevent at least some of the current received via the high-power interface  105  from flowing to the low-power module  112 . For example, the low-power module  112  may allow the multi-mode control device  102  to be powered by leaking current through to earth ground, as described above with respect to  FIG. 3 . The diode  402  may prevent or reduce the leakage to earth ground of current that is provided to the load device  116  via the high-power module  114  when the multi-mode control device  102  is in the high-power mode. 
     An output of the high-power module  114  can be electrically coupled to the anode of the diode  404 . An input of the processing device  302  or other low-power circuitry  110  can be electrically coupled to the cathode of the diode  404 . The diode  404  can prevent current from being provided to components of the multi-mode control device  102  other than the low-power circuitry  110 . For example, the diode  404  can prevent at least some of the current that flows through diode  402  from flowing toward the high-power module  114  or the high-power circuitry. For example, the low-power module  112  may allow the multi-mode control device  102  to be powered by a battery or other energy storage device having a finite energy supply. The diode  404  can prevent current from such alternative power sources from being siphoned away from the processing device  302  or the communication device  304 . 
     In the example depicted in  FIG. 6 , the low-power circuitry  110  includes the processing device  302  and the communication device  304 . In some aspects, the communication device  304  can require significant power for operation. For example, operating the communication device  304  continuously may quickly exhaust power that is available via the low-power module  112  when the load device  116  is not powered. The communication device  304  may be disabled during at least some portion of time in which the multi-mode control device  102  is in a low-power mode. In one example, the communication device  304  may be enabled for short periods of time during the low-power mode. For example, the processing device  302  can enable the communication device  304  by providing a current via an output of the processing device  302  to a base of a transistor  406 . Providing a current to the base of the transistor  406  can allow current to flow from the low-power module  112  through the transistor  406  to the communication device  304 . 
     In some aspects, the processing device  302  can operate at a full power or at other operational modes during periods of time when the multi-mode control device  102  is in a high-power mode. The processing device  302  can operate in a “sleep” or other low-power mode during at least some periods of time when the multi-mode control device  102  is in a low-power mode. For example, the processing device  302  may operate in different modes in implementations in which the low-power module  112  includes an energy storage device  214  having a finite supply of energy. An internal timing device can be used to activate the processing device  302  for switching the processing device  302  from a “sleep” or other lower power mode to a full power or other operational mode. Non-limiting examples of an internal timing device can include a watch crystal oscillator, an internal very-low-power low-frequency oscillator, and an internal digitally controlled oscillator. 
     In some aspects, the processing device  302  or one or more other suitable components of the control module  106  can be used to switch the multi-mode control device  102  to the low-power mode in which the multi-mode control device  102  is powered using the low-power module  112 . For instance,  FIG. 7  is a partial block diagram illustrating an alternative example of the multi-mode control device  102  in which the low-power interface  104  includes a transistor  502  or other suitable switching component that is used for providing power to the low-power circuitry  110 . 
     The processing device  302  can configure the transistor  502  or other suitable switching component to allow current flow to the low-power circuitry  110  based on a reading from sensing circuitry  508 . The sensing circuitry  508  can be electrically coupled to an input pin or other input port of the processing device  302 . The processing device  302  can determine, based on a value sampled from the input pin or other input port, that the low-power circuitry  110  is to be powered using the low-power module  112 . The processing device  302  can respond to the determination by providing, via an output pin or other output port of the processing device  302 , a current to a base of the transistor  502 . Providing a current to the base of the transistor  502  can allow current to flow from the low-power module  112  through the transistor  502  to the low-power circuitry  110 . 
     In some aspects, the sensing circuitry  508  can be electrically coupled to one or both of the low-power module  112  and the high-power module  114 , as depicted in  FIG. 7 . The sensing circuitry  508  can include one or more components that can be used to compare a first amount of current or voltage associated with the low-power module  112  with a second amount of current or voltage associated with the high-power module  114 . For example, a differential amplifier or other comparator can include a first input that is electrically coupled to the low-power module  112 , a second input that is electrically coupled to the high-power module  114 , and an output that is electrically coupled to an input pin or other input port of the processing device  302 . The processing device  302  can sample the current or voltage at the output of the sensing circuitry  508 . If the current or voltage at the first input is greater than the current or voltage at the second input (i.e., if the current used to energize the load has significantly decreased), a current or voltage at the output of the comparator can change. The processing device  302  can respond to the change in current or voltage by enabling the low-power module  112  to provide current to the processing device  302  (i.e., by switching on the transistor  506 ). At a subsequent point in time, if the current or voltage at the first input is less than the current or voltage at the second input (i.e., if the load current has significantly increased), a current or voltage at the output of the comparator can change again. The processing device  302  can respond to the additional change in current or voltage by preventing the low-power module  112  from providing current to the processing device  302  (i.e., by switching off the transistor  506 ). 
     Although  FIG. 7  depicts the sensing circuitry  508  as being electrically coupled to both the low-power module  112  and the high-power module  114 , other implementations are possible. For example, the sensing circuitry  508  may include a current sense resistor in an electrical path from the high-power module  114  to an input pin or other input port of the processing device  302 . The processing device  302  can sample the current or voltage at the input pin or other input port. The processing device  302  can switch on the transistor  506  in response to the sampled current or voltage failing to exceed a threshold current or voltage (e.g., when the load device  116  is powered off). The processing device  302  can switch off the transistor  506  in response to the sampled current or voltage exceeding a threshold current or voltage (e.g., when the load device  116  is powered on or otherwise energized). 
     In the example depicted in  FIG. 7 , the low-power circuitry  110  includes the processing device  302  and the communication device  304 . The diode  504  can prevent current that flows through the low-power module  112  from also flowing to the high-power module  114 . The diode  504  can thereby prevent current from being provided to components of the multi-mode control device  102  other than the low-power circuitry  110 . The communication device  304  may be disabled during at least some portion of time in which the multi-mode control device  102  is in a low-power mode. For example, the processing device  302  can enable the communication device  304  by providing a current via an output of the processing device  302  to a base of a transistor  506 . Providing a current to the base of the transistor  506  can allow current to flow from the low-power module  112  through the transistor  506  to the communication device  304 . 
     In some aspects, the processing device  302  can be used to control the charging of an energy storage device (e.g., a battery or capacitor) that is included in or electrically coupled to the low-power module  112 . For example,  FIG. 8  is a partial block diagram illustrating an alternative example of the multi-mode control device  102  in which an energy storage device  214  for providing power to the low-power circuitry  110  is configured to store energy when the multi-mode control device  102  is in a high-power mode. The processing device  302  can determine from the sensing circuitry  508  that the load device  116  is powered on, as described above with respect to  FIG. 7 . The processing device  302  can respond to determining that the load device  116  is powered on by configuring the charging circuitry  602  to allow power from the power source  202  to charge the energy storage device  214 . For example, the charging circuitry  602  can include one or more transistors in an electrical path between the power source  202  and the energy storage device  214 . The processing device  302  can configure the charging circuitry  602  to allow a charging current from the power source  202  to charge the energy storage device  214  by providing a current to the base of one or more transistors in the charging circuitry  602 . 
     In some aspects, the high-power circuitry  108  can include high-power sensing circuitry or components, such as (but not limited to) an occupancy sensor, a motion sensor, a proximity sensor, a video camera or image sensor, a network activity monitor, an RF radio, a vibration or position sensor, or any other type of suitable sensor device or group of devices. In the high-power mode, the control device  102  can operate the occupancy sensor or other high-power sensing circuitry. The occupancy sensor or other high-power sensing circuitry can be used to determine whether the control device  102  is to remain in the high-power mode. In the low-power mode, the control device  102  can use a trigger from a trigger detection device to determine whether to change the control device  102  from the low-power mode to the high-power mode. Examples of triggers received by trigger detection devices include (but are not limited to) a button press or other touch received by a button or touch sensor, RF energy received by an antenna, infrared energy received by a passive infrared sensor, infrared signals received by an infrared receiver by a remote infrared transmitter, vibrations received by a vibration sensor, sounds detected by a sound sensor, changes in temperature or other environmental conditions detected by an appropriate sensor, changes in light detected by a photocell or other sensor for sensing visible light, messages received by a network interface device, etc. 
     For instance,  FIG. 9  is a partial block diagram illustrating an alternative example of the multi-mode control device  102  that includes high-power sensing circuitry  708  and a trigger detection device  710 . Examples of the sensing circuitry  708  include an occupancy sensor, a motion sensor, a proximity sensor, a video camera or image sensor, a network activity monitor, an RF radio, a vibration or position sensor, or any other type of suitable sensor device or group of devices. Examples of the trigger detection device  710  include (but are not limited to) a button, a touch sensor, an antenna for receiving RF energy, a passive infrared sensor, an infrared receiver, a vibration sensor, a sound sensor, a temperature sensor, a heat sensor, a photocell or other sensor for sensing visible light, a network interface device, etc. 
     The sensing circuitry  708  can be powered by current received via the high-power interface  105 . The high-power interface  105  depicted in  FIG. 7  can include, for example, a diode  704  and circuitry for electrically coupling the high-power module  114  to the sensing circuitry  708  and the switching circuitry  306  via one or more electrical paths. The diode  704  can perform a similar function as the diode  404  described above with respect to  FIG. 6  or the diode  504  described above with respect to  FIG. 7 . Although the example of a high-power interface  105  depicted in  FIG. 9  includes a diode  704 , other implementations of a high-power interface  105  can be used for a control device  102  that includes high-power sensing circuitry  708 . 
     The trigger detection device  710  can be powered by current received via the low-power interface  104 . The low-power interface  104  depicted in  FIG. 7  can include, for example, a transistor  702  or other suitable switching component. The transistor  702  or other suitable switching component can perform a similar function as the transistor  502  described above with respect to  FIG. 7 . 
     The processing device  302  can configure the transistor  702  or other suitable switching component to allow current flow to the low-power circuitry  110  based on the processing device  302  determining that the control device  102  is in the low-power mode or is to enter the low-power mode. 
     In some aspects, the processing device  302  can determine that the control device  102  is in the low-power mode or is to enter the low-power mode based on information received from the sensing circuitry  708 . For example, sensing circuitry  708  such as an occupancy sensor, a motion sensor, a proximity sensor, a video camera or image sensor, a network activity monitor, an RF radio, a vibration or position sensor, or any other type of suitable sensor device or group of devices can be electrically coupled to an input pin or other input port of the processing device  302 . The processing device  302  can determine, based on a value sampled from the input pin or other input port, that the trigger detection device  710  and/or other the low-power circuitry  110  is to be powered using the low-power module  112 . The processing device  302  can respond to the determination by providing, via an output pin or other output port of the processing device  302 , a current to a base of the transistor  706 . Providing a current to the base of the transistor  706  can allow current to flow from the low-power module  112  through the transistor  706  to the trigger detection device  710  or other low-power circuitry  110 . 
     In additional or alternative aspects, the processing device  302  can determine that the control device  102  is in the low-power mode or is to enter the low-power mode based on information received from other sensing circuitry used to monitor current or power provided to the load device  116 , such as the sensing circuitry  508  depicted in  FIGS. 7 and 8 . In some aspects, the control device  102  can include a trigger detection device  710  and both sensing circuitry used to monitor current or power provided to the load device  116  (as depicted in  FIGS. 7-8 ) and high-power sensing circuitry  708  such as an occupancy sensor, a motion sensor, a proximity sensor, a video camera or image sensor, a network activity monitor, an RF radio, a vibration or position sensor, or any other type of suitable sensor device or group of devices. In other aspects, the control device  102  can include a trigger detection device  710  and sensing circuitry used to monitor current or power provided to the load device  116  (as depicted in  FIGS. 7-8 ), and an occupancy sensor or other high-power sensing circuitry  708  can be omitted. 
     In some aspects, the sensing circuitry  508  can be electrically coupled to one or both of the low-power module  112  and the high-power module  114 , as depicted in  FIG. 9 . The sensing circuitry  508  can include one or more components that can be used to compare a first amount of current or voltage associated with the low-power module  112  with a second amount of current or voltage associated with the high-power module  114 . For example, a differential amplifier or other comparator can include a first input that is electrically coupled to the low-power module  112 , a second input that is electrically coupled to the high-power module  114 , and an output that is electrically coupled to an input pin or other input port of the processing device  302 . The processing device  302  can sample the current or voltage at the output of the sensing circuitry  508 . If the current or voltage at the first input is greater than the current or voltage at the second input (i.e., if the current used to energize the load has significantly decreased), a current or voltage at the output of the comparator can change. The processing device  302  can respond to the change in current or voltage by enabling the low-power module  112  to provide current to the processing device  302  (i.e., by switching on the transistor  506 ). At a subsequent point in time, if the current or voltage at the first input is less than the current or voltage at the second input (i.e., if the load current has significantly increased), a current or voltage at the output of the comparator can change again. The processing device  302  can respond to the additional change in current or voltage by preventing the low-power module  112  from providing current to the processing device  302  (i.e., by switching off the transistor  506 ). 
     In additional or alternative aspects, the control device  102  having a trigger detection device  710  and high-power sensing circuitry  708  can also include the charging circuitry  602  and energy storage device  214 , as depicted in  FIG. 10 . The charging circuitry  602  and energy storage device  214  can be operated in a manner similar to that described above with respect to  FIG. 8 . 
     Although  FIGS. 9 and 10  omit a communication device  304  for simplicity of illustration, a control device  102  can be implemented using any combination of components depicted in  FIGS. 1-10 . For example, a control device  102  can include a processing device  302  having an output pin electrically coupled to a transistor or other switching component for operating a communication device  304  in a low-power mode or high-power mode, and the control device  102  can also include an additional output pin electrically coupled to a transistor or other switching component for operating a trigger detection device  710  in a low-power mode or high-power mode. In some aspects, the communication device  304  can be used as a trigger detection device  710  (e.g., for receiving a message indicating that the control device  102  is to be operated in a high-power mode). 
     Power Control Schemes Using Multi-Mode Control Device 
     In some aspects, the multi-mode control device  102  can be used to implement a power control scheme in which an occupancy sensor, a communication device, or another high-power receiving device (e.g., a motion sensor, a proximity sensor, a video camera or image sensor, a network activity monitor, an RF radio, a vibration or position sensor, or any other type of suitable sensor device or group of devices) can be operated in the high-power mode, and a low-power sensor or other suitable trigger detection device can be used in the low-power mode to determine whether to switch the control device  102  to the high-power mode. 
     For example,  FIG. 11  is a flow chart depicting an example of a process  800  using a multi-mode control device  102  to implement a power control scheme using a combination of high-power sensing circuitry and a low-power trigger detection device. The process is described with respect to the implementations described above with respect to  FIGS. 1-10 . However, other implementations are possible. 
     At block  802 , the process  800  involves powering, based on the control device  102  being in a high-power mode, a high-power receiver using a current from an electrical connection between a power source and a controlled load device  116 . The high-power receiver can include any device or group of devices that are powered using a current received from the high-power module  114  via the high-power interface  105 . In one example, the high-power receiver can be a communication device  304  that is powered using one or more of the implementations of the control device  102  depicted in  FIGS. 6-8 . In another example, the high-power receiver can be an occupancy sensor or other high-power sensing circuitry  708  that is powered using one or more of the implementations of the control device  102  depicted in  FIGS. 9-10 . In another example, the high-power receiver can be an occupancy sensor or other high-power sensing circuitry that is powered by using the processing device  302  to actuate a transistor or other switching component to provide an electrical path between the high-power module  114  and the high-power receiver. 
     At block  804 , the process  800  involves configuring the control device  102  to operate in a low-power mode by reducing current provided to the high-power receiver and powering a trigger detection device  710  using a current received from a low-power module. 
     For example, the control device  102  can power off or otherwise reduce power to the high-power receiver. In some aspects, the processing device  302  can deactivate a transistor or other switching component connecting the high-power receiver to an electrical path in which current flows. In other aspects, the processing device  302  can provide a control signal to the high-power receiver via a data bus of the control device  102  that instructs the high-power receiver to turn off or reduce power consumption. The control device can the load device  116  to reduce or cease its power consumption. In one example, the control device  102  can transmit a signal to a load controller  115  or directly to the load device  116  that causes the load device  116  to change from a powered-on state to a powered-off state. In another example, the control device  102  can configure one or more switching components in an electrical path between the load device  116  and a power source to reduce or prevent current flow to the load device  116 . 
     In some aspects, the control device  102  can power the trigger detection device  710  in the manner described above with respect to  FIG. 9 . For example, the processing device  302  can activate a transistor or other switching component that provides an electrical path for current to flow from the low-power module  112  to the trigger detection device  710 . 
     At block  806 , the process  800  involves waiting for a low-power trigger to be detected, received, or otherwise obtained by the trigger detection device  710 . In some aspects, detecting the trigger using the trigger detection device  710  involves detecting a touch via the trigger detection device  710 . For example, the trigger detection device  710  can be a touch sensor or a button included in or communicatively coupled to the control device  102 . In additional or alternative aspects, detecting the trigger using the trigger detection device  710  involves detecting energy received by the trigger detection device  710 . For example, the trigger detection device  710  can be a sensor or other suitable device included in or communicatively coupled to the control device  102  and configured to detect energy such as (but not limited to) RF energy, light energy in a visible spectrum, infrared light energy, and sound waves. In additional or alternative aspects, detecting the trigger using the trigger detection device  710  involves receiving a signal via the trigger detection device  710 . In one example, the trigger detection device  710  can be an infrared receiver included in or communicatively coupled to the control device  102  that can communicate with an infrared transmitter (e.g., a remote control used to operate the control device  102 ). In another example, the trigger detection device  710  can be a network interface device or other communication device  304  included in or communicatively coupled to the control device  102  that can receive data messages. In additional or alternative aspects, detecting the trigger using the trigger detection device  710  involves detecting other environmental changes using the trigger detection device  710 . Examples of such environmental changes include changes in temperature, heat flow, vibration, etc. 
     At block  808 , the process  800  involves determining whether a trigger has been detected, received, or otherwise obtained by the trigger detection device  710 . If a trigger is not present, the process  800  can return to block  806 . 
     If a trigger is present, the process  800  involves configuring the control device  102  to operate in the high-power mode for operating the occupancy sensor, as depicted at block  810 . For example, the control device  102  can cause power consumption by the load device  116  to increase. The control device  102  can transmit a signal to a load controller  115  and/or the load device  116  that causes the load device  116  to enter a powered-on state. Power can be provided to the high-power receiver. The processing device  302  may, for example, activate a transistor or other suitable switching component to allow current to flow to the high-power receiver from the high-power interface  105 . 
     In additional or alternative aspects, the control device  102  can be operated in an interim mode in which the processing device  302  verifies that the control device  102  should switch from the high-power mode to the low-power mode. For example,  FIG. 12  is a flow chart depicting an example of a process  900  using a multi-mode control device  102  to implement a power control scheme involving an interim power mode using a combination of high-power sensing circuitry and a low-power trigger detection device. The process is described with respect to the implementations described above with respect to  FIGS. 1-10 . However, other implementations are possible. 
     At block  902 , the process  900  involves powering, based on the control device  102  being in a high-power mode, a high-power receiver using a current from an electrical connection between a power source and a controlled load device  116 . Block  902  can be implemented in a manner similar to that described above with respect to block  802  in  FIG. 11 . 
     At block  904 , the process  900  involves receiving switching information indicating that the control device  102  is to enter the low-power mode. 
     In some aspects, switching information can include a signal or other information generated by manually actuating the control device  102 . In one example, a button communicatively coupled to the processing device  302  can be pressed. The button press can indicate that the load device  116  is to be powered off or that the control device  102  is to enter a low-power state. In another example, a signal can be received by the communication device  304  from a remote control. The received signal can indicate that the load device  116  is to be powered off or that the control device  102  is to enter a low-power state. 
     In additional or alternative aspects, switching information can include a signal or other information generated by powering off or otherwise reducing the power provided to the load device  116 . For example, the sensing circuitry  508  depicted in  FIGS. 7-8  can be used by the processing device  302  to determine that the power provided to the load device  116  has decreased below a threshold amount. The power decreasing by a threshold amount can indicate that the control device  102  should enter a low-power mode. 
     At block  906 , the process  900  involves determining an occupancy status in an area serviced by the load device  116 . In an interim mode in which occupancy status is determined, the control device  102  can determine the occupancy status using the high-power receiver. In one example, a high-power receiver such as a communication device  302  can communicate with an occupancy sensor or other high-power sensing circuitry remote from the control device  102  to determine the occupancy status. The processing device  302  can receive one or more messages via the communication device  302  to determine the occupancy status. In another example, a high-power receiver such as an occupancy sensor included in the control device  102  can be used to determine the occupancy status. 
     The processing device  302  can determine whether the occupancy status corresponds to a condition for entering the low-power mode. For example, the control device  102  can cause the load device  116  to be powered off in response to and immediately after receiving switching information. In a time period subsequent to the control device  102  causing the load device  116  to be powered off or otherwise changing the state of the load device  116 , the processing device  302  can cause power to be provided to the high-power receiver for receiving occupancy information. After causing the causing the load device  116  to be powered off or otherwise changing the state of the load device  116 , the processing device  302  can start a timer corresponding to the specified time period. If occupancy is sensed during the time period (e.g., before the timer expires), the control device  102  can change the state of the load device  116  (e.g., cause the load device  116  to be powered on) and remain in the high-power mode (i.e., the detected occupancy information is not consistent with entering the low-power mode). If occupancy is not sensed during the time period (e.g., before the timer expires), the multi-mode control device  102  can refrain from changing the state of the load device  116  (e.g., allow the load device to remain powered off) and enter the low-power mode (i.e., the detected occupancy information is consistent with entering the low-power mode). The time period can be determined or otherwise obtained in any suitable manner. In some aspects, the area is monitored for a period of time that is determined or otherwise obtained based on a fixed setting for the time period. In additional or alternative aspects the area is monitored for a period of time that is determined or otherwise obtained based on a user-programmable setting for the time period. In additional or alternative aspects the area is monitored for a period of time that is determined or otherwise obtained based on a programmed setting that is automatically adjusted based on power consumption patterns. 
     If the occupancy status does not correspond to a condition for entering the low-power mode, the process  900  returns to block  902 . 
     If the occupancy status corresponds to a condition for entering the low-power mode, the process  900  involves configuring the control device  102  to operate in a low-power mode by reducing current provided to the high-power receiver and powering a trigger detection device  710  using a current received from a low-power module, as depicted at block  908 . The control device  102  can be switched to the low-power mode based on receiving the switching information at block  904  and determining the occupancy status at block  906 . Block  908  can be implemented in a manner similar to that described above with respect to block  804  in  FIG. 11 . 
     At block  910 , the process  900  involves waiting for a low-power trigger to be detected, received, or otherwise obtained by the trigger detection device  710 . Block  910  can be implemented in a manner similar to that described above with respect to block  806  in  FIG. 11 . 
     At block  912 , the process  900  involves determining whether a trigger has been detected, received, or otherwise obtained by the trigger detection device  710 . If a trigger is not present, the process  900  can return to block  910 . 
     If a trigger is present, the process  900  involves configuring the control device  102  to operate in the high-power mode for operating the occupancy sensor, as depicted at block  914 . Block  914  can be implemented in a manner similar to that described above with respect to block  810  in  FIG. 11 . 
     In additional or alternative aspects, other power control schemes can be implemented using the control device  102 . For example, in some aspects, when the load device  116  is not energized, the multi-mode control device  102  can be powered using the low-power module  112  to provide an amount of power sufficient to detect a button being pressed. When the load device  116  is energized, the multi-mode control device  102  can be powered by using the high-power module to harvest or otherwise obtain energy from current flowing through the load device  116 . The amount of power used by the multi-mode control device  102  in the high-power mode can be sufficient to power a communication device  304  and/or other high-power circuitry  108 . 
     In some aspects, the multi-mode control device  102  can switch between the low-power mode and the high-power mode based on information received from a sensor. For example, the communication device  304  can receive signals from a wireless occupancy sensor that is remote from the multi-mode control device  102 . The signals can include occupancy information for a location that is serviced by the load device  116 . The processing device  302  can obtain the occupancy information from the communication device  304 . If the processing device  302  determines from the occupancy information that the location is occupied, the processing device  302  can refrain from changing the state of the load device  116  (e.g., allow a lighting device to remain in an “on” state). If the processing device  302  determines from the occupancy information that the location is not occupied, the processing device  302  can respond to receiving the occupancy information by changing the state of the load device  116  (e.g., setting the lighting device to an “off” state). 
     The processing device  302  can also respond to receiving information indicating that the location is no longer occupied by configuring the multi-mode control device  102  to enter the low-power mode. For example, a processing device  302  can turn on a transistor or use another switching component to allow current to flow to the processing device  302  from the low-power module  112 , as described above with respect to  FIG. 7 . In some aspects, the low-power mode can allow the multi-mode control device  102  to detect a button press or another manual input that causes the multi-mode control device  102  to switch from the low-power mode to the high-power mode. In some aspects, in the low-power mode, the multi-mode control device  102  can periodically enable the communication device  304  in order to receive additional information (e.g., occupancy information). The processing device  302  can respond to the additional information by configuring the multi-mode control device  102  to switch from the low-power mode to the high-power mode. 
     In some aspects, the load device  116  can remain energized for a period of time after an occupancy sensor or other high-power sensing circuitry indicates that a location is no longer occupied. During this period, the load device  116  emits an indicator (e.g., a flashing light) that the load device  116  will be de-energized. If occupancy is sensed during the time period, the multi-mode control device  102  can refrain from changing the state of the load device  116 . If occupancy is not sensed during the time period, the multi-mode control device  102  can change the state of the load device  116  (i.e., cause the load device  116  to be powered off). 
     In additional or alternative aspects, the multi-mode control device  102  can change the state of the load device  116  immediately after receiving information indicating that a location is not occupied. For example, the control device  102  can cause the load device  116  to be powered off in response to and immediately after determining that the location is not occupied. In a time period subsequent to the control device  102  causing the load device  116  to be powered off or otherwise changing the state of the load device  116 , the processing device  302  can cause power to be provided to the communication device  304  to allow the communication device  304  to subsequently receive occupancy information from a remote wireless occupancy sensor. After causing the causing the load device  116  to be powered off or otherwise changing the state of the load device  116 , the processing device  302  can start a timer corresponding to the specified time period. In some aspects, the processing device  302  can cause power to be provided to the communication device  304  continuously during the time period. In other aspects, the processing device  302  can cause power to be provided to the communication device  304  periodically or otherwise intermittently during the time period. If occupancy is sensed during the time period (e.g., before the timer expires), the multi-mode control device  102  can change the state of the load device  116  (e.g., cause the load device  116  to be powered on). If occupancy is not sensed during the time period (e.g., before the timer expires), the multi-mode control device  102  can refrain from changing the state of the load device  116  (e.g., allow the load device to remain powered off). 
     In additional or alternative aspects, the multi-mode control device  102  can be used to provide automatic dimming control based on harvesting of power from an environment in which the load device  116  is positioned (e.g., harvesting power from light energy). Data from a remote wireless daylight harvesting sensor can be received by the multi-mode control device  102  via a communication device  304 . The multi-mode control device  102  can cause power to be removed from the load device  116  in response to determining that a threshold amount of ambient energy (e.g., light) is available in the environment. The processing device  302  can periodically enable the communication device  304  during a low-power mode to receive information about the amount of ambient energy in the environment (e.g., daylight harvesting information). The multi-mode control device  102  can cause the load device  116  to be energized in response to the processing device  302  determining that a threshold amount of ambient energy (e.g., light) is not available in the environment. 
     In additional or alternative aspects, the processing device  302  can periodically enable the communication device  304  during a low-power mode in order to receive a message from another device indicating that the load device  116  should be energized. The processing device  302  can respond to the receipt of such a message via the communication device  304  by configuring the multi-mode control device  102  to energize the load device  116 . The processing device  302  can also respond to the receipt of this message by enabling the communication device  304  for continuous operation (i.e., by configuring the multi-mode control device  102  for operation in the high-power mode). 
       FIGS. 13-16  depict examples of processes used by the control device  102  to implement some of the features described above. 
       FIG. 13  is a flow chart depicting an example of a process  1000  for operating a multi-mode control device  102  using a combination of manual inputs and information received from an occupancy sensor or other high-power sensing circuitry. The process  1000  is described with respect to the implementations described above with respect to  FIGS. 1-10 . However, other implementations are possible. In some aspects, one or more operations described herein with respect to  FIG. 13  can be used to implement one or more operations described above with respect to  FIGS. 11 and 12 . 
     At block  1002 , the process  1000  starts. At block  1004 , the process  1000  involves the load device  116  being powered. For example, the load device  116  can be powered using current provided by a power source  202 . The control device  102 , which may be in a low-power mode as described above with respect to  FIGS. 1-10 , can transmit a signal to a load controller  115  and/or the load device  116  that causes the load device  116  to enter a powered-on state. At block  1006 , the process  1000  involves providing power to a high-power receiver (e.g., an occupancy sensor or other sensing circuitry  708 , a radio or other communication device  304 , etc.) of the control device  102 . In some aspects, the processing device  302  can configure the control device  102  to enter or maintain a high-power mode. Configuring the control device  102  to enter or maintain a high-power mode can allow power to be provided to the high-power receiver (e.g., by receiving current via a high-power interface  105  to a high-power module  114 , as described above with respect to  FIGS. 1-10 ). The processing device may, for example, activate a transistor  406  or other suitable switching component (as described above with respect to  FIG. 6 ) to allow current to flow to the communication device  304  from one or both of the low-power interface  104  and the high-power interface  105 . In other aspects, the control device  102  can enter a high-power mode with requiring an operation by the processing device  302 . For example, in the implementation depicted in  FIG. 5 , the high-power mode can involve current being received by the communication device  304  and other high-power circuitry  108  via electrical circuitry  301 . 
     At block  1008 , the process  1000  involves waiting for a manual actuation (e.g., a button press, a touch to a touch sensor, etc.) at the control device  102 . For example, the processing device  302  can monitor an input received via an input pin or other port of the processing device  302  that is electrically coupled to a button, a touch sensor, or other component or group of components of the control device  102  that allow a user to manually actuate the control device  102  (e.g., by toggling the control device  102  between a low-power mode and a high-power mode). In some aspects, the control device  102  can be in a high-power mode described above with respect to  FIGS. 1-10  when the processing device  302  monitors the input pin or other input port for a button press or other manual actuation. At block  1010 , the process  1000  involves determining whether a manual actuation has been performed at the control device  102 . The button or other manual input component can be used to toggle or otherwise change the state of the load device  116  between a powered state and an unpowered state. The button or other manual input can also be used to change the state of the control device  102  between a high-power mode and a low-power mode. The processing device  302  can determine that the manual actuation has been performed at the control device  102  based on a signal or other input detected by the processing device  302 . The processing device  302  can detect a signal or other input at an input pin or other port of the processing device  302  that is electrically coupled to a button or other manual input component of the control device  102 . If a button or other manual input component is pressed or otherwise actuated at block  1010 , the process  1000  involves powering off the high-power receiver, as depicted at block  1018  and described below. 
     If a manual actuation is not performed, the process  1000  involves waiting for information to be received by the control device  102  via the high-power receiver, as depicted at block  1012 . For example, the processing device  302  can communicate with the communication device  304  and/or the sensing circuitry  708  via an internal data bus to receive a message or other information. In one example, the communication device  304  may receive a message from another device such as (but not limited to) an occupancy sensor in a location serviced by the load device  116 . In another example, the sensing circuitry  708  may detect occupancy or a lack thereof in a location serviced by the load device  116  or the control device  102  and provide occupancy information to the processing device  302 . In some aspects, the control device  102  can be in a high-power mode described above with respect to  FIGS. 1-10  when the processing device  302  communicates with the high-power receiver. 
     At block  1014 , the process  1000  involves determining whether a message or other information has been received by the control device  102 . If a message or other information has not been received by the control device  102 , the process  1000  can return to block  1008  and wait for a manual actuation. If the high-power receiver receives a message or other information, the processing device  302  can determine whether the message or other information indicates that a location serviced by the load device  116  is occupied, as depicted at block  1016 . In one example, the processing device  302  can reference data in a message received by the communication device  304  and determine from the data whether an occupancy sensor or other high-power sensing circuitry has detected activity indicative of occupancy in the serviced location. In one example, the processing device  302  can reference data received by an occupancy sensor or other sensing circuitry  708  and determine from the data whether activity indicative of occupancy has been detected. If the message or other information indicates that a location serviced by the load device  116  or control device  102  is occupied, the process  1000  can return to block  1008  and wait for a manual actuation. If the message or other information indicates that a location serviced by the load device  116  is not occupied, the process  1000  can proceed to block  1018 . 
     At block  1018 , the process  1000  involves powering off the high-power receiver if a manual actuation is detected at block  1010  and/or a lack of occupancy is determined at block  1016 . For example, in some aspects, the processing device  302  can deactivate a transistor or other switching component (depicted above in  FIGS. 5-7 ) connecting the communication device  304  or other high-power receiver to an electrical path in which current flows. In other aspects, the processing device  302  can configure the control device  102  to enter or maintain a low-power mode as described above with respect to  FIGS. 1-10 . Entering the low-power mode can cause the high-power receiver to be powered off. In other aspects, the processing device  302  can provide a control signal to the communication device  304  via a data bus of the control device  102  that instructs the communication device  304  to turn off. 
     At block  1020 , the process  1000  involves removing power from the load device  116 . In one example, the control device  102  can transmit a signal to a load controller  115  or directly to the load device  116  that causes the load device  116  to change from a powered-on state to a powered-off state. In another example, the control device  102  can configure one or more switching components in an electrical path between the load device  116  and a power source to reduce or prevent current flow to the load device  116 . 
     In some aspects, the control device  102  can enter or maintain a low-power mode based on the load device  116  changing from a powered-on state to a powered-off state without action by the processing device  302 . For example, in the implementations depicted in  FIGS. 4 and 5 , the load device  116  changing from a powered-on state to a powered-off state can result in a cessation or reduction of current being received via the high-power interface  105  (e.g., a circuit path  301  and/or a diode  404 ). This cessation or reduction of current can cause the low-power module  112  to be the primary or only source of power for the control device  102 . 
     In other aspects, the processing device  302  can configure the control device  102  to enter or maintain a low-power mode prior to or concurrently with transmitting the signal that causes the load device  116  to change from a powered-on state to a powered-off state. For example, the processing device  302  can activate a transistor or other switching component as described above with respect to  FIGS. 5-6  prior to or concurrently with transmitting the signal that causes the load device  116  to change from a powered-on state to a powered-off state. In other aspects, the processing device  302  can configure the control device  102  to enter or maintain a low-power mode subsequent to the load device  116  changing from a powered-on state to a powered-off state. For example, the processing device  302  can activate a transistor or other switching component as described above with respect to  FIGS. 5-6  after sensing circuitry  508  is used to detect that the load device  116  has entered a powered-off state or other low-power state. 
     At block  1022 , the process  1000  involves waiting for a low-power trigger to be detected by a trigger detection device  710 . For example, in a low-power mode, the processing device  302  of the control device  102  can monitor an input pin or other input port that is communicatively coupled to a trigger detection device  710 . In the low-power mode, current received by the control device  102  via the low-power interface  104  can be sufficient to power the processing device  302  for this monitoring operation. The trigger detection device  710  can be used to detect a signal, energy, data, or other trigger indicating that the control device  102  should toggle or otherwise change the state of the load device  116  between an unpowered state and a powered state. In one example, pressing a button or actuating some other manual input can configure the control device  102  to transmit a signal to the load controller  115  and/or the load device  116  to change the state of the load device  116 . The button or other manual input can also be used to change the state of the control device  102  between a low-power mode and a high-power mode. In another example, receiving passive infrared energy via a passive infrared sensor of the control device  102  can cause the control device  102  to transmit a signal to the load controller  115  and/or the load device  116  to change the state of the load device  116 . The detection of the passive infrared energy can also be used to change the state of the control device  102  between a low-power mode and a high-power mode. Any other suitable examples of triggers described above with respect to  FIG. 7  can also be used at block  1022 . 
     At block  1024 , the process  1000  involves determining whether a low-power trigger has been detected. A low-power mode of the control device  102  can involve providing sufficient power to the processing device  302  to detect a low-power trigger using the trigger detection device  710 . For example, in a low-power mode, the processing device  302  can determine whether a button has been pressed, passive infrared energy has been received, or any other suitable trigger has been detected based on a reading from an input pin or other input port that is communicatively coupled to the trigger detection device  710 . If a low-power trigger has been detected, the process  1000  can return to block  1004 , which involves providing power to the load device  116 . The process  1000  can continue as described above. If a low-power trigger has not been detected, the process  1000  can return to block  1022 . 
       FIG. 14  is a flow chart depicting an example of a process  1100  for operating a multi-mode control device  102  using a combination of manual inputs and information received from a light sensor. The process  1100  is described with respect to the implementations described above with respect to  FIGS. 1-10 . However, other implementations are possible. In some aspects, one or more operations described herein with respect to  FIG. 14  can be used to implement one or more operations described above with respect to  FIGS. 11 and 12 . 
     At block  1102 , the process  1100  starts. At block  1104 , the process  1100  involves the load device  116  being powered. For example, the load device  116  can be powered using current provided by a power source  202 . At block  1106 , the process  1100  involves providing power to a high-power receiver (e.g., an occupancy sensor or other sensing circuitry  708 , a radio or other communication device  304 , etc.). Block  1106  can be implemented in a manner similar to that described above with respect to block  1006  in  FIG. 13 . For example, the processing device  302  can configure the control device  102  to enter or maintain a high-power mode such that power is provided to the communication device  304 . 
     At block  1108 , the process  1100  involves waiting for a manual actuation (e.g., a button press, a touch to a touch sensor, etc.) at the control device  102 . Block  1108  can be implemented in a manner similar to that described above with respect to block  1008  in  FIG. 13  For example, the processing device  302  can monitor an input received via an input pin or other port of the processing device  302  that is electrically coupled to a button or other manual input of the control device  102 . At block  1110 , the process  1100  determines whether a manual actuation has been performed at the control device  102 . Block  1110  can be implemented in a manner similar to that described above with respect to block  1010  in  FIG. 13 . 
     If a manual actuation is not performed, the process  1100  involves waiting for information to be received by the control device  102  via the high-power receiver, as depicted at block  1112 . Block  1112  can be implemented in a manner similar to that described above with respect to block  1012  in  FIG. 13 . For example, the processing device  302  can communicate with the communication device  304  via an internal data bus to receive a message or other information that the communication device  304  may receive from another device, such as (but not limited to) an light sensor in a location serviced by a load device  116  that is controlled by the control device  102 . 
     At block  1114 , the process  1100  involves determining whether a message or other information has been received by the control device  102 . Block  1114  can be implemented in a manner similar to that described above with respect to block  1014  in  FIG. 13 . If a message or other information has not been received by the control device  102 , the process  1100  can return to block  1108 . If the high-power receiver receives a message or other information, the processing device  302  can determine a level of daylight or other light level indicated by the message, as depicted at block  1116 . For example, the processing device  302  can reference data in a message received by the communication device  304  and determine from the data whether a light level provided by the load device  116  is too high or too low, whether the light level provided by the load device  116  is sufficient, or whether it is acceptable to remove electric light provided by the load device  116 . If the message or other information indicates that a light level provided by the load device  116  is too high or too low, the process  1100  involves adjusting a dimming level, as depicted at block  1118 . For example, the control device  102  can transmit a signal to a load controller  115  or directly to the load device  116  that causes the load device  116  to adjust a level of light provided in the location. If the light level provided by the load device  116  is sufficient, the process  1100  can return to block  1108 . If it is safe or otherwise acceptable to remove electric light provided by the load device  116 , the process  1100  can proceed to block  1120 . 
     At block  1120 , the process  1100  involves powering off the high-power receiver if a manual actuation is detected at block  1110  and/or it is determined at block  1116  that it is acceptable to remove electric light. Block  1120  can be implemented in a manner similar to that described above with respect to block  1018  in  FIG. 13 . At block  1122 , the process  1100  involves removing power from the load device  116 . Block  1122  can be implemented in a manner similar to that described above with respect to block  1020  in  FIG. 13 . 
     At block  1124 , the process  1100  involves waiting for a low-power trigger to be detected by a trigger detection device  710 . Block  1124  can be implemented in a manner similar to that described above with respect to block  1022  in  FIG. 13 . At block  1126 , the process  1100  involves determining whether a low-power trigger has been detected. Block  1126  can be implemented in a manner similar to that described above with respect to block  1024  in  FIG. 13 . If a low-power trigger has been detected, the process  1100  can return to block  1104 . If not, the process  1100  can return to block  1124 . 
       FIG. 15  is a flow chart depicting an example of a process  1200  for operating a multi-mode control device  102  using a combination of manual inputs, sensor information received from an occupancy sensor or other high-power sensing circuitry, and control messages from a remote control device. The process  1200  is described with respect to the implementations described above with respect to  FIGS. 1-10 . However, other implementations are possible. In some aspects, one or more operations described herein with respect to  FIG. 15  can be used to implement one or more operations described above with respect to  FIGS. 11 and 12 . 
     At block  1202 , the process  1200  starts. At block  1204 , the process  1200  involves the load device  116  being powered. For example, the load device  116  can be powered using current provided by a power source  202 . At block  1206 , the process  1200  involves providing power to a high-power receiver (e.g., an occupancy sensor or other sensing circuitry  708 , a radio or other communication device  304 , etc.). Block  1206  can be implemented in a manner similar to that described above with respect to block  1006  in  FIG. 13 . For example, the processing device  302  can configure the control device  102  to enter or maintain a high-power mode such that power is provided to the communication device  304 . At block  1208 , the process  1200  involves waiting for a manual actuation (e.g., a button press, a touch to a touch sensor, etc.) at the control device  102 . Block  1208  can be implemented in a manner similar to that described above with respect to block  1008  in  FIG. 13 . For example, the processing device  302  can monitor an input received via an input pin or other port of the processing device  302  that is electrically coupled to a button or other manual input of the control device  102 . 
     At block  1210 , the process  1200  involves determining whether a manual actuation has been performed at the control device  102 . Block  1210  can be implemented in a manner similar to that described above with respect to block  1010  in  FIG. 13 . 
     If a manual actuation is not performed, the process  1200  involves waiting for information to be received by the control device  102  via the high-power receiver, as depicted at block  1212 . Block  1212  can be implemented in a manner similar to that described above with respect to block  1012  in  FIG. 13 . For example, the processing device  302  can communicate with the communication device  304  via an internal data bus to receive a message or other information that the communication device  304  may receive from another device, such as (but not limited to) an occupancy sensor or other high-power sensing circuitry in a location serviced by a load device  116  controlled by the control device  102  or a remote control device within a communication range of the control device  102 . 
     At block  1214 , the process  1200  involves determining whether a message or other information has been received by the control device  102 . Block  1214  can be implemented in a manner similar to that described above with respect to block  1014  in  FIG. 13 . For example, if a message or other information has not been received by the control device  102 , the process  1200  can return to block  1208 . If the high-power receiver receives a message or other information, the processing device  302  can determine whether the message or other information indicates that the location is occupied, as depicted at block  1216 . Block  1216  can be implemented in a manner similar to that described above with respect to block  1016  in  FIG. 13 . If the message or other information indicates that the location is occupied, the process  1200  can return to block  1208 . If the message or other information indicates that the location is not occupied, the process  1200  can proceed to block  1220 . 
     If the message or other information is not indicative of occupancy in the location, the process  1200  involves determining whether the message or other information is indicative of a remote switch press from a remote control device, as depicted in block  1218 . For example, the processing device  302  can reference data in a message received by the communication device  304  from a remote control device to determine if a remote switch press has been received from a remote control device. If a remote switch press has not been received from a remote control device, the process  1200  can return to block  1208 . If a remote switch press has been received from a remote control device, the process  1200  can proceed to block  1220 . 
     At block  1220 , the process  1200  involves powering off the high-power receiver if a manual actuation is detected at block  1210 , if occupancy is determined at block  1216 , and/or if a remote switch press is determined at block  1218 . Block  1220  can be implemented in a manner similar to that described above with respect to block  1018  in  FIG. 13 . At block  1222 , the process  1200  involves removing power from the load device  116 . Block  1222  can be implemented in a manner similar to that described above with respect to block  1020  in  FIG. 13 . 
     At block  1224 , the process  1200  involves waiting for a low-power trigger to be detected by a trigger detection device  710 . Block  1224  can be implemented in a manner similar to that described above with respect to block  1022  in  FIG. 13 . At block  1226 , the process  1200  involves determining whether a low-power trigger has been detected. Block  1226  can be implemented in a manner similar to that described above with respect to block  1024  in  FIG. 13 . If a low-power trigger has been detected, the process  1200  can return to block  1204 . If not, the process  1200  involves powering high-power receiver (e.g., a radio or other communication device  304 ) for a time period, as depicted at block  1228 . 
     At block  1230 , the process  1200  involves determining whether a message or other information has been received during the time period. Block  1230  can be implemented in a similar manner as that described above with respect to block  1214 . If a message or other information has been received during the time period, the process  1200  involves determining whether the message or other information indicates that the location is occupied, as depicted at block  1232 . Block  1232  can be implemented in a manner similar to that described above with respect to block  1216 . If a message or other information has not been received during the time period, the process  1200  involves powering off a radio or other communication device  304 , as depicted at block  1234 . The process can return to block  1224 . 
       FIG. 16  is a flow chart depicting an example of a process  1300  for operating a multi-mode control device  102  using a combination of manual inputs, information from sensors, and voltage detection at the load device  116 . The process  1300  is described with respect to the implementations described above with respect to  FIGS. 1-10 . However, other implementations are possible. In some aspects, one or more operations described herein with respect to  FIG. 16  can be used to implement one or more operations described above with respect to  FIGS. 11 and 12 . 
     At block  1302 , the process  1300  starts. At block  1304 , the process  1300  involves the load device  116  being powered. For example, the load device  116  can be powered using current provided by a power source  202 . At block  1306 , the process  1300  involves providing power to a high-power receiver (e.g., an occupancy sensor or other sensing circuitry  708 , a radio or other communication device  304 , etc.). Block  1306  can be implemented in a manner similar to that described above with respect to block  1006  in  FIG. 13 . 
     At block  1308 , the process  1300  involves waiting for a manual actuation (e.g., a button press, a touch to a touch sensor, etc.) at the control device  102 . Block  1308  can be implemented in a manner similar to that described above with respect to block  1008  in  FIG. 13 . For example, the processing device  302  can monitor an input received via an input pin or other port of the processing device  302  that is electrically coupled to a button or other manual input of the control device  102 . At block  1310 , the process  1300  involves determining whether a manual actuation has been performed at the control device  102 . Block  1310  can be implemented in a manner similar to that described above with respect to block  1010  in  FIG. 13 . 
     If a manual actuation is not performed, the process  1300  involves waiting for information to be received by the control device  102  via the high-power receiver, as depicted at block  1312 . Block  1312  can be implemented in a manner similar to that described above with respect to block  1012  in  FIG. 13 . For example, the processing device  302  can communicate with the communication device  304  via an internal data bus to receive a message or other information that the communication device  304  may receive from another device, such as (but not limited to) an occupancy sensor or other high-power sensing circuitry in a location serviced by a load device  116  controlled by the control device  102  or a remote control device within a communication range of the control device  102 . 
     At block  1314 , the process  1300  involves determining whether a message or other information has been received by the control device  102 . Block  1314  can be implemented in a manner similar to that described above with respect to block  1014  in  FIG. 13 . For example, if a message or other information has not been received by the control device  102 , the process  1300  can return to block  1308 . If the high-power receiver receives a message or other information, the processing device  302  can determine whether the message or other information indicates that the location is occupied, as depicted at block  1316 . Block  1316  can be implemented in a manner similar to that described above with respect to block  1016  in  FIG. 13 . If the message or other information indicates that the location is occupied, the process  1300  can return to block  1308 . If the message or other information indicates that the location is not occupied, the process  1300  can proceed to block  1320 . 
     If the message or other information is not indicative of occupancy in the location, the process  1300  involves determining whether the message or other information is indicative of a remote switch press from a remote control device, as depicted in block  1318 . For example, the processing device  302  can reference data in a message received by the communication device  304  from a remote control device to determine a remote switch press has been received from a remote control device. If not, the process  1300  can return to block  1308 . If so, the process  1300  can proceed to block  1320 . 
     At block  1320 , the process  1300  involves powering off the high-power receiver if a manual actuation is detected at block  1310 , if occupancy is determined at block  1316 , and/or if a remote switch press is determined at block  1318 . Block  1320  can be implemented in a manner similar to that described above with respect to block  1018  in  FIG. 13 . At block  1322 , the process  1300  involves removing power from the load device  116 . Block  1322  can be implemented in a manner similar to that described above with respect to block  1020  in  FIG. 13 . 
     At block  1324 , the process  1300  involves waiting for a low-power trigger to be detected by a trigger detection device  710 . Block  1324  can be implemented in a manner similar to that described above with respect to block  1022  in  FIG. 13 . At block  1326 , the process  1300  involves determining whether a low-power trigger has been detected. Block  1326  can be implemented in a manner similar to that described above with respect to block  1024  in  FIG. 13 . If a low-power trigger has been detected, the process  1300  can return to block  1304 . If not, the process  1300  involves determining whether a voltage or current is detectable at the load device  116 , as depicted at block  1328 . For example, the processing device  302  can use sensing circuitry to determine if a voltage or current is present at the load device  116 , as described above with respect to  FIGS. 6 and 7 . If a voltage is detectable at the load device  116 , the process  1300  can return to block  1304 . If a voltage is not detectable at the load device  116 , the process  1300  can return to block  1324 . 
     The foregoing is provided for purposes of illustrating, describing, and explaining aspects of the present invention and is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Further modifications and adaptation to these embodiments will be apparent to those skilled in the art and may be made without departing from the scope and spirit of the invention. Different aspects described above can be combined with one another.