×

System and method for determining user input and interference on an input device

  • US 9,367,181 B2
  • Filed: 03/08/2011
  • Issued: 06/14/2016
  • Est. Priority Date: 03/08/2011
  • Status: Active Grant
First Claim
Patent Images

1. A processing system for a capacitive input device, the capacitive input device comprising a transmitter sensor electrode and a receiver sensor electrode capacitively coupled to the transmitter sensor electrode, wherein the processing system comprises:

  • transmitter circuitry configured to drive a transmitter signal onto the transmitter sensor electrode, the transmitter signal comprising a transmitter waveform with repeating cycles, wherein each cycle of the transmitter waveform includes a first transition;

    receiver circuitry configured to receive, from the receiver sensor electrode, a resulting signal, the resulting signal including effects corresponding to the transmitter signal and indicative of a user input in the sensing region; and

    accumulator circuitry configured to, for each cycle of the transmitter waveform;

    separately accumulate a first portion of the resulting signal using a first channel with a first capacitor and produce a first accumulation used for determining the user input, andaccumulate a second portion of the resulting signal using a second channel and produce a second accumulation used for determining interference,wherein the second portion is accumulated during a reset period that is non-coterminous with the first portion, andwherein the first accumulation is discharged from the first capacitor during the reset period.

View all claims
  • 3 Assignments
Timeline View
Assignment View
    ×
    ×