Abstract: Systems, methods, and computer-readable media for enabling a power efficient stylus for an electronic device are provided. Various components may be provided for providing electrostatic discharge protection of such a stylus.

Abstract: Touch-based input devices, such as a stylus, can receive tactile input from a user. The tactile input functions can be performed by a touch sensor, such as a capacitive sensing device. A touch sensor can be integrated into a stylus in a low profile form. Tactile input can be received at the user's natural grip location. Furthermore, the stylus can effectively distinguish between tactile inputs from a user and disregard sustained tactile inputs that are provided while the user simply holds the stylus at the user's natural grip location.

Abstract: A stylus input device can allow a user to interface with an external electronic device. The stylus can provide an additional or alternative input to the external electronic device in response to a user applying a compressive force to the device housing. The stylus can include multiple sensors to provide a signal in response to the compressive force applied to the stylus.

Abstract: An electrostatic discharge (ESD) robust design for an input device such as a stylus is disclosed. The input device can include one or more components, such as one or more Schottky diodes, that can be damaged by ESD events. To reduce the likelihood of damage to sensitive components, the parasitic capacitance between sensitive conductive paths and reference ground paths of the input device that could otherwise provide electrostatic discharge paths can be reduced (arranging current limiting resistance at specific locations among sensitive components, creating physical separation between sensitive conductive paths and reference ground paths), shielding can be added to shield the sensitive electronics from ESD pulses, and high dielectric breakdown material can be added to prevent ESD pulse entry or exit of not otherwise protected circuit parts.

Abstract: In some examples, a stylus can include a conductive shield. In some examples, the conductive shield can include a plurality of traces along an edge of a printed circuit board (PCB) including the stylus circuitry. In some examples, the conductive shield can include a shield can coupled to the PCB and disposed around the components of the stylus circuitry. In some examples, the conductive shield can include a hollow portion into which the stylus circuitry can be disposed and a solid portion that can act as a reference electrode. In some examples, the conductive shield can include a hollow sleeve disposed around the stylus circuitry. In some examples, the conductive sleeve can be attached to the PCB. In some examples, the conductive sleeve can be disposed between layers of a housing of the stylus. In some examples, the conductive sleeve can be integrated with the stylus housing.

Abstract: Touch-based input devices, such as a stylus, can receive tactile input from a user. The tactile input functions can be performed by a touch sensor, such as a capacitive sensing device. A touch sensor can be integrated into a stylus in a low profile form. Tactile input can be received at the user's natural grip location. Furthermore, the stylus can effectively distinguish between tactile inputs from a user and disregard sustained tactile inputs that are provided while the user simply holds the stylus at the user's natural grip location.

Abstract: Input device power consumption can be reduced with a magnetic drive system. In some examples, the input device can include a transformer configured to generate a desired high output voltage from logic-level input pulses. In some examples, the distributed capacitance and associated resonance of the transformer can act as a low-pass filter, and can create a relatively clean output waveform from input logic signal waveforms. In some examples, the transformer can be an autotransformer. In some examples, to stabilize an amplitude of the output by sampling the output of the transformer and adjusting the input to the transformer based on the sampled output.

Abstract: A level of wear of a stylus tip can be estimated and in accordance with a determination that the level of wear of the stylus tip exceeds a threshold, the stylus input functionality of an electronic device can be disabled. The threshold can be set such that the stylus can be disabled before the stylus sensing performance degrades to a degree perceptible to a human and/or before exposing internal portions of the stylus that can scratch a touch screen. Additionally or alternatively, a notification can be provided to indicate to a user that the stylus tip should be replaced. In some examples, the estimated level of wear can also be used to provide warning notifications. Stylus tip wear can be estimated, for example, based on a detected total signal strength or based on an estimated total distance traversed by the stylus tip across a surface.

Abstract: A ring electrode to determine the orientation of the stylus relative to the surface. The stylus can include a ring electrode configuration which can improve capacitive coupling between the ring electrode and the touch panel. The ring electrode configuration can include a ring electrode and ground ring, and ground plate. By varying the lengths of ring electrode, ground ring, ground plate, and the distance between these elements, the electric field emanating from the ring electrode can be tuned to optimize the capacitive coupling between the ring electrode and surface. In some examples, the ring electrode can include multiple sub-rings. In some examples, the ring electrode can comprise a crown shape including projections, each having a width that tapers to a minimum width along the length of the ring electrode.

Abstract: An electrode for an input device can be designed to reduce wobble over a range of input device orientations. The electrode can include a spherical portion and a tapered portion. In some examples, the electrode can linearly taper away from the spherical portion. In other examples, the electrode can non-linearly taper away forming an elliptical flare. Additionally or alternatively, the electrode can include a spring-loaded member that can couple the electrode to other circuitry of the input device. Additionally or alternatively, the electrode can include a neck portion coupled to the tapered portion, and part of the neck portion can be shielded. The input device can include a first non-conductive material disposed on part of the spherical portion of the electrode and a second non-conductive material disposed between part of the electrode and the first non-conductive material.