Abstract: A wireless power system may have a wireless power transmitting device and a wireless power receiving device. The wireless power receiving device may have a coil that receives wireless power signals from the wireless power transmitting device and may have a rectifier that produces direct-current power from the received wireless power signals. A charging status indicator may be displayed by the wireless power receiving device during wireless power transmission. Control circuitry in the wireless power receiving device may monitor the output voltage to determine whether wireless power transmission has been lost. The charging status indicator may continue to be displayed for a debounce period following detection of loss of wireless power transmission. The debounce period may be adjusted based on whether power loss is due to user movement of the receiving device or termination of power transmission by the transmitting device.

Abstract: A wireless power system may have a wireless power transmitting device and wireless power receiving devices. The wireless power transmitting device has wireless power transmitting circuitry with coils to transmit wireless power to wireless power receiving devices. The wireless power receiving devices are placed on the wireless power transmitting device in an order. Batteries in the wireless power receiving devices are charged based at least partly on the order. Power allocation is based on utilization factor information such as information on a power draw associated with each of the power receiving devices. Measurement circuitry in the wireless power transmitting device is used to gather impedance images from the coils. Changes in the impedance images are used to temporarily halt power transmission. Power transmission is resumed depending on whether in-band communications are lost or are maintained.

Abstract: A wireless power system may have a wireless power transmitting device and a wireless power receiving device. The wireless power receiving device may have a coil that receives wireless power signals from the wireless power transmitting device and may have a rectifier that produces direct-current power from the received wireless power signals. A charging status indicator may be displayed by the wireless power receiving device during wireless power transmission. Control circuitry in the wireless power receiving device may monitor the output voltage to determine whether wireless power transmission has been lost. The charging status indicator may continue to be displayed for a debounce period following detection of loss of wireless power transmission. The debounce period may be adjusted based on whether power loss is due to user movement of the receiving device or termination of power transmission by the transmitting device.

Abstract: A wireless power system may have a wireless power transmitting device and wireless power receiving devices. The wireless power transmitting device has wireless power transmitting circuitry with coils to transmit wireless power to wireless power receiving devices. The wireless power receiving devices are placed on the wireless power transmitting device in an order. Batteries in the wireless power receiving devices are charged based at least partly on the order. Power allocation is based on utilization factor information such as information on a power draw associated with each of the power receiving devices. Measurement circuitry in the wireless power transmitting device is used to gather impedance images from the coils. Changes in the impedance images are used to temporarily halt power transmission. Power transmission is resumed depending on whether in-band communications are lost or are maintained.