Abstract: Devices and techniques are generally described for a doorbell camera circuit architecture. In some examples, at least one processor of a doorbell device may generate a first control signal. The at least one processor may send the first control signal to a power-switching control circuit of the doorbell device. The power-switching control circuit may receive a first input electrical signal. The power-switching control circuit may store at least a portion of energy associated with the first input electrical signal in a plurality of capacitors of the power-switching control circuit. The power-switching control circuit may supply power from the plurality of capacitors to a camera of the doorbell device during a first state of the control signal. In various examples, the power-switching control circuit may supply power from the battery to the camera of the doorbell device during a second state of the control signal.

Abstract: Techniques are generally described for motion detection by supplying voltage pulses to a radio frequency (RF) circuit. In some examples, an RF motion detection circuit may output a first RF signal based at least in part on a first voltage pulse. In some further examples, the RF motion detection circuit may receive a second RF signal, the second RF signal being the first RF signal reflected from an environment external to the RF motion detection circuit. In some further examples, the first RF signal and the second RF signal may be mixed to generate a difference component signal. A first output voltage representing the difference component signal may be generated. In some examples, the first output voltage may be used to detect motion in the environment.

Abstract: Techniques are generally described for controlling a camera to capture video based on one or more auxiliary motion sensors. First data indicative of motion may be received from a first motion sensor at a camera. In some examples, the first motion sensor may have a first field-of-view. Second data indicative of motion may be received from a second motion sensor at the camera device. In some examples, the second motion sensor may have a second field-of-view different than the first field-of-view. A determination may be made that the first data temporally corresponds to the second data. In some examples, an image sensor of the camera may capture first image data in response to the first data indicative of motion and the second data indicative of motion.