Abstract:
Systems and methods for multi-state switch networks and multi-state LED networks are provided. Systems and methods for maintaining the brightness of LEDs in multi-state LED networks are also provided. The multi-state networks contain control circuitry that can output a single control signal that is able to drive a pair of diodes in three different states. In a network of 2*N diodes, N wires are sufficient to drive the diodes in 3N different states. The control circuitry may also include a pulse-width modulator that controls the perceived brightness of the LEDs in a multi-state LED network in response to a voltage level of the power source.
Abstract:
Personal listening device (PLD) includes earphone housing having therein (a) inertial sensor to detect motion of PLD and to generate motion signal, (b) pressure sensor to detect compression of portion of PLD and to generate pressure sensor signal, and (c) speaker to receive anti-noise signal and desired audio signal from electronic device, and active noise control (ANC) system to generate anti-noise signal as being one of first or second anti-noise signal. ANC system includes processor, vibration detector to detect vibration of the PLD based on at least one of motion signal or pressure sensor signal, and ANC anti-noise generator to generate first anti-noise signal when vibrations are not detected by vibration detector, and to generate second anti-noise signal when vibrations are detected by vibration detector. Second anti-noise signal is based on detected vibrations. Processor reconfigures ANC system for ANC anti-noise generator to generate second anti-noise signal. Other embodiments are described.
Abstract:
Electronic devices and accessories such as headsets for electronic devices are provided. A microphone may be included in an accessory to capture sound for an associated electronic device. Buttons and other user interfaces may be included in the accessories. An accessory may have an audio plug that connects to a mating audio jack in an electronic device, thereby establishing a wired communications link between the accessory and the electronic device. The electronic device may include power supply circuitry for applying bias voltages to the accessory. The bias voltages may bias a microphone and may adjust settings in the accessory such as settings related to operating modes. User input information may be conveyed between the accessory and the electronic device using ultrasonic tone transmission. The electronic device may also gather input from the accessory using a voltage detector coupled to lines in the communications path.