SUPPLEMENTAL POWER SUPPLY FOR A BATTERY-POWERED DEVICE
A battery-powered device, such as a motorized window treatment, may provide power to an electrical load, such as a motor. The device may also include a control circuit and a communication circuit. In addition to the battery, the device may be configured to receive power from a supplemental power source, such as a solar cell or wireless RF power supply, through which to power the control and communication circuits. The device may include a voltage monitor and a switch to intelligently control whether the battery or the supplemental power source is powering the control and communication circuits.
1 . An electric load control apparatus, comprising:
an electric motor conductively coupled to a primary power source that outputs a first voltage range; and
a switching circuit reversibly transitionable between:
a first state in which the switching circuit conductively couples to the primary power source one or more electric loads operable at a second voltage range less than the first voltage range; and
a second state in which the switching circuit conductively couples the one or more electric loads to a supplemental power source that provides an output voltage that varies over time; and
a monitor circuit to:
measure the output voltage of the supplemental power source;
determine whether the output voltage of the supplemental power source is within a defined voltage range; and
responsive to the determination that the measured output voltage of the supplemental power source is within the defined voltage range, placed the switching circuit in the second state.
2 . The electric load control apparatus of claim 1 , wherein the one or more electric loads include a power converter circuit to provide a voltage output in the second voltage range.
3 . The electric load control apparatus of claim 2 wherein the one or more electric loads further include a communication circuit and a motor control circuit.
4 . The electric load control apparatus of claim 3 wherein the communication circuit includes a wireless communication circuit.
5 . The electric load control apparatus of claim 4 wherein the wireless communication circuit is reversibly transitionable between a SLEEP state and an ACTIVE state.
6 . The electric load control apparatus of claim 5 wherein the wireless communication circuit monitors for a presence of a wireless control signal when in the ACTIVE state.
7 . The electric load control apparatus of claim 6 wherein the wireless communication circuit causes the motor control circuit to transition to the ACTIVE state responsive to detection of the wireless control signal.
8 . The electric load control apparatus of claim 3 wherein the motor control circuit is reversibly transitionable between a SLEEP state and an ACTIVE state.
9 . The electric load control apparatus of claim 8 wherein the communication circuit causes the motor control circuit to transition to the ACTIVE state responsive to reception of a wireless control signal.
10 . The electric load control apparatus of claim 1 further comprising a window treatment operatively coupled to the electric motor.
11 . The electric load control apparatus of claim 1 wherein the supplemental power source comprises one or more photovoltaic cells.
12 . The electric load control apparatus of claim 1 wherein the supplemental power source comprises a radio frequency (RF) energy scavenging circuit.
13 . The electric load control apparatus of claim 1 wherein the supplemental power source further comprises one or more energy storage devices.
14 . A motorized window treatment comprising:
an electric motor conductively coupled to a primary power source that provides a first output voltage;
a supplemental power source that includes power generation circuitry and one or more energy storage devices that provide a second output voltage that varies over time; and
a switching circuit reversibly transitionable between:
a first position that conductively couples a motor control circuit to the first output voltage; and
a second position that conductively couples the motor control circuit to a supplemental power source to the second output voltage; and
a monitor circuit to:
measure the second output voltage;
determine whether the second output voltage falls within a defined voltage range; and
responsive to the determination that the measured second output voltage of is within the defined voltage range, place the switching circuit in the second position.
15 . The motorized window treatment of claim 14 wherein the primary power source comprises one or more energy storage devices.
16 . The motorized window treatment of claim 14 wherein the power generation circuitry includes one or more photovoltaic devices.
17 . The motorized window treatment of claim 14 wherein the power generation circuitry includes one or more radio frequency (RF) energy scavenging circuits.