US 10,768,746 B1 · Quasi-continuous-time sampling of discrete-time sampled signals

Abstract

Improved sensing can include modified sampling and/or processing to improve performance against noise due to environmental variations and interference. In some examples, improved interference rejection can be achieved by sampling a sensor multiple times during settled periods. In some examples, the excitation signal and sampling window can be dynamically adjusted to satisfy drift and/or interference specifications based on various operating conditions or the operating environment. In some examples, drift performance can be traded off to improve interference performance. In some examples, improved immunity to environmental variations can be achieved by equalizing sensor outputs in accordance with characterization of the sensing system. In some examples, improved performance can be achieved by sampling the sensor continuously and using an optimized window function to improve performance against noise.

Claims19

Dependent claims

An apparatus comprising:

a sensor configured to be coupled to an electrode of a touch sensor panel;
and
one or more processors coupled to the sensor and configured to:
select a first excitation signal and a first sampling window, wherein the first sampling window corresponds to a settled portion of an output of the sensor in which the output is within a threshold of a predetermined settled value, and wherein the first sampling window and the first excitation signal are selected based on at least one of a drift specification and an interference specification;
stimulate the sensor with the first excitation signal;
in response to stimulating the sensor with the first excitation signal, sample the sensor a plurality of times during the first sampling window, without sampling the sensor while the sensor is coupled to the electrode of the touch sensor panel before the first sampling window, to generate a first plurality of samples;
and
generate a first capacitance measurement for the sensor based on the first plurality of samples.

5 more elements

A non-transitory computer readable storage medium storing one or more programs, the one or more programs comprising instructions, which when executed by a device including one or more processors, causes the device to perform a method comprising:

selecting a first excitation signal and a first sampling window, wherein the first sampling window corresponds to a settled portion of an output of the sensor in which the output is within a threshold of a predetermined settled value, and wherein the first sampling window and the first excitation signal are selected based on at least one of a drift specification and an interference specification;
stimulating a sensor with the first excitation signal, the sensor configured to be coupled to an electrode of a touch sensor panel;
in response to stimulating the sensor with the first excitation signal, sampling the sensor a plurality of times during the first sampling window, without sampling the sensor while the sensor is coupled to the electrode of the touch sensor panel before the first sampling window, to generate a first plurality of samples;
and
generating a first capacitance measurement for the sensor based on the first plurality of samples.

2 more elements

Dependencies are inferred from the claim text.

Quasi-continuous-time sampling of discrete-time sampled signals

Life of this patent

Quasi-continuous-time sampling of discrete-time sampled signals

Life of this patent

Abstract

Claims19