Abstract: In one embodiment, a method includes generating a first drive signal for transmission to one or more drive lines of a capacitive touch sensor. The first drive signal comprising a function pattern with a first predetermined frequency. The method also includes receiving a sense signal from one or more sense lines of the touch sensor. The sense signal results at least in part from charge transfer driven by the first drive signal. The method also includes, by a bandpass filter with a first center frequency substantially synchronized to the first predetermined frequency, filtering out components of the sense signal outside a range of the first center frequency; and communicating from the bandpass filter to a processor a passband signal that comprises components of the sense signal within the range of the first center frequency.

Abstract: In one embodiment, a stylus has one or more electrodes and one or more non-transitory computer-readable storage media embodying logic for communicating wirelessly with a device through a touch sensor of the device. The media further embodies logic configured to receive from a tactile element tactile-input signals based on tactile input to the stylus by an entity and process those signals to determine an action. The media further embodies logic configured to provide tactile-output signals to a tactile element of the stylus to communicate tactile output to the entity.

Abstract: In one embodiment, a stylus includes one or more electrodes and one or more computer-readable non-transitory storage media embodying logic for transmitting signals wirelessly to a device through a touch sensor of the device. The computer-readable non-transitory storage media of the stylus further embodies logic for allocating between the stylus and the device electric energy available at the stylus or the device based on one or more first criteria.

Abstract: In one embodiment, a stylus receives a signal, the stylus being able to wirelessly transmit signals to and receive signals from a device, and the stylus having a plurality of electrodes disposed in a tip of the stylus. The stylus compares a first value of the signal to a first threshold and determines whether to start a timing period based at least in part on this comparison. If the timing period is started, the stylus compares a second value of the signal to a second threshold and determines whether to stop the timing period based at least in part on this second comparison. If the timing period is stopped, the stylus determines whether the duration of the timing period is within a pre-determined range of timing period values. If so, the stylus processes the signal.

Abstract: In one embodiment, an apparatus comprises a data-transmitting component and a data-receiving component. The data-transmitting component is operable to: select a set of first reference values and a set of second reference values respectively indicating a lower bound and an upper bound of a range of values; respectively represent the set of first reference values and the set of second reference values as a set of first pulses and a set of second pulses; represent a set of analog values as a set of third pulses, each third pulse having a third amplitude between the first amplitude of a corresponding first pulse and the second amplitude of a corresponding second pulse that is determined based on a percentage of the corresponding analog value within the range of values; and transmit the set of first pulses, the set of third pulses, and the set of second pulses to the data-receiving component.

Abstract: In one embodiment, a stylus includes one or more electrodes and one or more computer-readable non-transitory storage media embodying logic for transmitting signals wirelessly from the stylus to a device through a touch sensor of the device. The stylus has one or more sensors for kinetic, thermal, solar or electric energy harvesting from an environment of the stylus or from the stylus itself.

Abstract: In one embodiment, an apparatus comprises a sense unit and a drive unit. The sense unit is operable to sense a first signal from drive lines of a touch sensor. The touch sensor comprises the drive lines and sense lines arranged relative to the drive lines such that intersections of the drive lines and the sense lines form one or more capacitive nodes. The drive unit is operable to transmit a second signal based on the first signal to the sense lines such that transmission of the second signal changes the perceived capacitance of the one or more capacitive nodes.

Abstract: In one embodiment, a stylus includes electrodes operable to transmit signals wirelessly to a device through a touch sensor of the device. The stylus also includes one or more computer-readable non-transitory storage media within the stylus and embodying logic that is operable when executed to access first data representing a gesture made with the stylus by a user, such as a sequence of manipulations of the stylus. The logic is further operable to access second data representing a pre-defined authentication sequence and compare the first data with the second data. This comparison may authenticate the user to the stylus or the device, authenticate the stylus to the device or the user, or authenticate the device to the stylus or the user.

Abstract: In one embodiment, a method includes accessing, by a stylus, data associated with a particular user of the stylus, the data associated with the particular user being stored in a memory of the stylus; and by the stylus, wirelessly transmitting the data to a device in response to the stylus contacting a touch sensor of the device.

Abstract: In one embodiment, a method includes in an inductive-sensing mode, by a controller, applying an alternating-current (AC) signal on a first electrode of a capacitive touch sensor. The capacitive touch sensor is configured to operate in the inductive-sensing mode and a capacitive-sensing mode. The method also includes sensing a signal indicative of a magnetic field on the first electrode. The signal is due at least in part to a magnetic field generated by the object and the magnetic field is generated at least in part in response to the AC signal applied on the first electrode. The method also includes determining a position of the object generating the magnetic field based on the signal indicative of the magnetic field.

Abstract: In one embodiment, a method includes accessing, by a stylus, data indicating a customization of a device for the particular user. The stylus is associated with a particular user and is configured to transmit signals wirelessly to the device through a touch sensor of the device. The data indicating the customization is stored in a memory of the stylus. The method also includes wirelessly transmitting the data by the stylus to the device through the touch sensor of the device to affect the customization of the device for the particular user.

Abstract: In one embodiment, a stylus has one or more sensors that detect the movement of the stylus, such as an accelerometer, a gyroscope, or a magnetometer. The stylus wirelessly transmits signals to a device based on the movement of the stylus.

Abstract: In one embodiment, a method includes receiving at a stylus a receive signal from a device. The stylus includes one or more computer-readable media embodying logic, and the device includes a touch sensor. The receive signal is received at the stylus through the touch sensor of the device and one or more electrodes of the stylus. The method includes filtering the receive signal for processing by the logic and processing, by the logic, the receive signal as filtered.

Abstract: In one embodiment, a device includes a form factor of a stylus. The form factor includes a surface area. The device also includes one or more substrates disposed along one or more portions of the surface area; and one or more touch sensors disposed on one or more of the substrates. At least one of the touch sensors includes a distinct touch-sensitive area that includes a touch-sensitive button, a touch-sensitive wheel, or a touch-sensitive slider. The device also includes a computer-readable non-transitory storage medium coupled to one or more of the touch sensors and embodying logic configured to associate the distinct touch-sensitive area with a pre-determined function of the device.

Abstract: In one embodiment, an apparatus includes a stylus nib of a stylus. The stylus nib comprising a tapered end. The apparatus also includes a rolling-ball tip. At least a portion of the rolling-ball tip is housed within the tapered end of the stylus nib, and the rolling-ball tip includes an electrode configured to transmit a signal wirelessly to a device through a touch-sensor of the device.

Abstract: In one embodiment, a stylus operable to communicate wirelessly with a device through a touch sensor of the device contains one or more computer-readable non-transitory storage media embodying logic that is operable when executed to access first data representing a recently occurred authentication event involving the stylus or the device. The logic is further operable to access second data representing a pre-defined authentication event. The logic is further operable to compare the first data with the second data to authenticate a user to the stylus or the device, a stylus to the user or the device, or a device to the user or the stylus.

Abstract: In one embodiment, computer-readable non-transitory storage media receive one or more signals based on motion of an object, a device, or both. The received signals are compared to a motion profile which defines unintended motion of the object, the device, or both, and this comparison determines whether any of the signals represent unintended motion of the stylus or device. The received signals are then processed to correct for the unintended motion defined by the motion profile.

Abstract: In one embodiment, a method includes receiving sensor data from one or more sensors in or on a stylus, the stylus including one or more electrodes and one or more computer-readable non-transitory storage media embodying logic for wirelessly transmitting signals to a device through a touch sensor of the device. The method includes generating a carrier signal and modulating the carrier signal to communicate the sensor data and wirelessly transmitting from the stylus to the device the carrier signal as modulated through the touch sensor of the device.

Abstract: In one embodiment, a stylus includes one or more electrodes and one or more computer-readable non-transitory storage media embodying first logic for transmitting signals wirelessly to a device through a touch-sensor of the device. The stylus has a first power mode in which components of the stylus for receiving signals from or transmitting signals to the device are powered off; a second power mode in which components of the stylus for receiving signals from the device are powered on at least periodically and components of the stylus for transmitting signals to the device are powered off; and a third power mode in which components of the stylus for transmitting signals to the device are powered on at least periodically. The media further embodies second logic for transitioning the stylus from one of the first, second, and third power modes to another one of the first, second, and third power modes.

Abstract: In one embodiment, an apparatus comprises a touch sensor comprising a touch-sensitive area, and a touch-sensor controller coupled to the touch sensor. The touch-sensor controller is operable when executed to: select one or more regions associated with a stylus within the touch-sensitive area, and scan one or more electrodes within each region.