Methods and systems for detecting a position-based attribute of an object using digital codes

摘要

Methods, systems and devices are described for detecting a position-based attribute of a finger, stylus or other object with a touchpad or other sensor having a touch-sensitive region that includes a plurality of electrodes. Modulation signals for one or more electrodes are produced as a function of any number of distinct digital codes. The modulation signals are applied to an associated at least one of the plurality of electrodes to obtain a resultant signal that is electrically affected by the position of the object. The resultant signal is demodulated using the plurality of distinct digital codes to discriminate electrical effects produced by the object. The position-based attribute of the object is then determined with respect to the plurality of electrodes from the electrical effects.

主权项

1. A controller configured to sense an input object in a sensing region of a sensing device, the controller comprising:
drive circuitry coupled to a first transmitter electrode and a second transmitter electrode and configured to simultaneously apply a first modulation signal to the first transmitter electrode and a second modulation signal to the second transmitter electrode, wherein the first modulation signal is based on a first one of a plurality of distinct digital codes and the second modulation signal is based on a second one of the plurality of distinct digital codes; and receive circuitry coupled to a plurality of receiver electrodes and configured to receive resultant signals with the plurality of receiver electrodes, the resultant signals comprising electrical effects associated with the first and second modulation signals; wherein the controller is configured to determine positional information for the input object based on the on the resultant signals.