Dynamic self-capacitive measurement acquisition
View Patent ↗Sensor circuitry is configured to perform, for a sensing frame, mutual capacitive sensing to obtain mutual capacitive measurements, and perform, for the sensing frame, first self-capacitive sensing to obtain first self-capacitive measurements, and perform second self-capacitive sensing to obtain a second self-capacitive measurements. Processing circuitry is connected to the sensor circuitry and is configured to detect an inconsistency between the mutual capacitive measurements and the first self-capacitive measurements, and halt, in response to detecting the inconsistency, a second sensing frame to trigger performing the second self-capacitive sensing. The second sensing frame is subsequent to the first sensing frame. The processing circuitry is further configured to determine intermittent interference using the first self-capacitive measurements and the second self-capacitive measurements.
1. A processing system for interference management in capacitive touch input detection that uses mutual capacitive sensing and self-capacitive sensing, comprising: sensor circuitry configured to:
perform, at a first sensing frame, a first mutual capacitive sensing to obtain a first mutual capacitive measurement, and
perform, at the first sensing frame, a first self-capacitive sensing to obtain a first self-capacitive measurement; and
processing circuitry coupled to the sensor circuitry and configured to:
detect whether a first inconsistency exists between the first mutual capacitive measurement and the first self-capacitive measurement;
halt, in response to detecting the first inconsistency, a second sensing frame subsequent to the first sensing frame, to trigger a second self-capacitive sensing to obtain a second self-capacitive measurement;
determine, using the first self-capacitive measurement and the second self-capacitive measurement, a type of interference from the first inconsistency;
perform interference mitigation on the self-capacitive measurements based on the determined type of interference; and
proceed, in response to not detecting the first inconsistency, to the second sensing frame to trigger the second mutual-capacitive sensing to obtain a second mutual capacitive measurement.
2. The processing system of claim 1 , wherein the processing circuitry is further configured to:
determine, in response to not detecting the inconsistency, positional information for any input object in a sensing region using the second sensing frame.
3. The processing system of claim 1 , wherein the sensor circuitry is further configured to:
perform third self-capacitive sensing to obtain a third self-capacitive measurement; and
wherein the processing circuitry is connected to the sensor circuitry and configured to:
trigger performing the third self-capacitive sensing in response to detecting interference,
compare the third self-capacitive measurement with the first mutual capacitive measurement, and
detect a second inconsistency between the third self-capacitive measurement and the first mutual capacitive measurement.
4. The processing system of claim 3 , wherein the processing circuitry is further configured to:
compare the third self-capacitive measurement with the second self-capacitive measurement,
detect a consistency between the third self-capacitive measurement and the second self-capacitive measurement, and
perform baseline error mitigation based on detecting the second inconsistency and detecting the consistency.
5. The processing system of claim 3 , wherein the processing circuitry is further configured to:
compare the third self-capacitive measurement with the second self-capacitive measurement, and
detect a third inconsistency between the third self-capacitive measurement and the second self-capacitive measurement.
6. The processing system of claim 5 , wherein the processing circuitry is further configured to:
perform intermittent interference mitigation based on detecting the third inconsistency.
7. The processing system of claim 6 , wherein performing the intermittent interference mitigation comprises changing a frequency of a subsequent self-capacitive sensing from a frequency used to perform the first self-capacitive sensing.
8. A method for interference management in capacitive touch input detection that uses mutual capacitive sensing and self-capacitive sensing, comprising:
performing, at a first sensing frame, a first mutual capacitive sensing to obtain a first mutual capacitive measurement;
performing, at the first sensing frame, a first self-capacitive sensing to obtain a first self-capacitive measurement;
detecting whether a first inconsistency exists between the first mutual capacitive measurement and the first self-capacitive measurement;
halting, in response to detecting the first inconsistency, a second sensing frame subsequent to the first sensing frame, to trigger a second self-capacitive sensing to obtain a second self-capacitive measurement;
determining, using the first self-capacitive measurement and the second self-capacitive measurement, a type of interference from the first inconsistency;
performing interference mitigation on the self-capacitive measurements based on the determined type of interference; and
proceeding, in response to not detecting the first inconsistency, to the second sensing frame to trigger the second mutual-capacitive sensing to obtain a second mutual capacitive measurement.
9. The method of claim 8 , further comprising:
determining, in response to not detecting the inconsistency, positional information for any input object in a sensing region using the first self-capacitive measurement and the first mutual capacitive measurement.
10. The method of claim 8 , further comprising:
triggering performing third self-capacitive sensing in response to detecting interference;
performing the third self-capacitive sensing to obtain a third self-capacitive measurement;
comparing the third self-capacitive measurement with the first mutual capacitive measurement; and
detecting a second inconsistency between the third self-capacitive measurement and the first mutual capacitive measurement.
11. The method of claim 10 , further comprising:
comparing the third self-capacitive measurement with the second self-capacitive measurement;
detecting a consistency between the third self-capacitive measurement and the second self-capacitive measurement; and
performing baseline error mitigation based on detecting the second inconsistency and detecting the consistency.
12. The method of claim 10 , further comprising:
comparing the third self-capacitive measurement with the second self-capacitive measurement; and
detecting a third inconsistency between the third self-capacitive measurement and the second self-capacitive measurement.
13. The method of claim 12 , further comprising:
performing intermittent interference mitigation based on detecting the third inconsistency.
14. The method of claim 13 , wherein performing the intermittent interference mitigation comprises changing a frequency of subsequent self-capacitive sensing from a frequency used to perform the first self-capacitive sensing.
15. An input device for interference management in capacitive touch input detection that uses mutual capacitive sensing and self-capacitive sensing, comprising:
a plurality of sensor electrodes configured to acquire a first mutual capacitive measurement and a first self-capacitive measurement of a sensing region; and
a processing system coupled to the plurality of sensor electrodes and configured to:
perform, for a first sensing frame, a first mutual capacitive sensing to obtain the first mutual capacitive measurement,
perform, for the first sensing frame, a first self-capacitive sensing to obtain the first self-capacitive measurement,
detect whether a first inconsistency exists between the first mutual capacitive measurement and the first self-capacitive measurement,
halt, in response to detecting the first inconsistency, a second sensing frame subsequent to the first sensing frame, to trigger a second self-capacitive sensing to obtain a second self-capacitive measurement;
determine, using the first self-capacitive measurement and the second self-capacitive measurement, a type of interference from the first inconsistency;
perform interference mitigation on the self-capacitive measurements based on the determined type of interference; and
proceed, in response to not detecting the first inconsistency, to the second sensing frame to trigger the second mutual-capacitive sensing to obtain a second mutual capacitive measurement.
16. The input device of claim 15 , wherein the processing system is further configured to:
trigger performing third self-capacitive sensing in response to detecting interference,
perform the third self-capacitive sensing to obtain a third self-capacitive measurement,
compare the third self-capacitive measurement with the first mutual capacitive measurement, and
detect a second inconsistency between the third self-capacitive measurement and the mutual capacitive measurement.
17. The input device of claim 16 , wherein the processing system is further configured to:
compare the third self-capacitive measurement with the second self-capacitive measurement, and
detect a third inconsistency between the third self-capacitive measurement and the second self-capacitive measurement.