# US 12,182,366 B2 · Distributed analog display noise suppression circuit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,182,366 B2 - Document ID: US12182366B2 - Status: Granted - Kind: B2 - Application number: 18/402,872 - Filed: 2024-01-03 - Published: 2024-05-09 - Granted: 2024-12-31 - Earliest claimed: 2020-04-14 - Assignees: Synaptics Incorporated - Applicants: Synaptics Incorporated - Inventors: Chunbo Liu; Mihai Bulea - Web page: https://patentgrep.com/patent/US12182366B2 ## CPC - G06F 3/04182: {Filtering of noise external to the device and not generated by digitiser components} - G06F 3/044: by capacitive means - G06F 3/0416: {Control or interface arrangements specially adapted for digitisers} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract A processing system including an amplifier configured to generate, from multiple spatial-common-mode-processed signals, a spatial common mode estimate and multiple feedback signals. The processing system includes multiple charge integrators configured to obtain resulting signals from the capacitive sensor electrodes, each of the resulting signals including a spatial common mode component and a residual noise component. The charge integrators generate multiple spatial-common-mode-processed signals by mitigating the spatial common mode component and the residual noise component in the resulting signals using the feedback signals. The processing system includes a programmable gain amplifier configured to determine the spatial common mode estimate. ## Claims ### Claim 1 A system, comprising: an amplifier configured to receive a plurality of processed signals; a feedback circuit coupled to an output of the amplifier and configured to generate a plurality of feedback signals, wherein each of the plurality of feedback signals includes a spatial common mode estimate and a residual noise suppression estimate, and wherein the feedback circuit comprises: a switch array and a string of resistors, wherein resistors of the string of resistors are coupled in series, and wherein the switch array is configured for selection of respective feedback signals of the plurality of feedback signals from respective nodes in the string of resistors; and a controller coupled to the feedback circuit and configured to process the spatial common mode estimate. ### Claim 2 (depends on 1) The system of claim 1, further comprising: a plurality of charge integrators configured to: receive a plurality of resulting signals from a plurality of capacitive sensor electrodes, wherein each of the plurality of resulting signals comprises a spatial common mode component and a residual noise component; and generate the plurality of processed signals based at least in part on the plurality of resulting signals. ### Claim 3 (depends on 2) The system of claim 2, wherein the residual noise suppression estimate is associated with a corresponding residual noise component associated with one of the plurality of capacitive sensor electrodes. ### Claim 4 (depends on 2) The system of claim 2, wherein the plurality of charge integrators are further configured to receive the plurality of feedback signals; and wherein generating the plurality of processed signals comprises mitigating the spatial common mode component and the residual noise components in the plurality of resulting signals using the plurality of feedback signals. ### Claim 5 (depends on 1) The system of claim 1, wherein each of the plurality of feedback signals is weighted by a respective weight value. ### Claim 6 (depends on 5) The system of claim 5, wherein each of the plurality of feedback signals corresponds to a respective feedback channel, and a respective weighted feedback signal for a respective feedback channel is based at least in part on the spatial common mode estimate and a channel-specific residual noise suppression estimate. ### Claim 7 (depends on 5) The system of claim 5, wherein a respective weighted feedback signal for a respective ith feedback channel comprises a respective weighted feedback voltage Vrefi, wherein: Vrefi=Vmod+ki(ΣVni/Σki) where ki is a weight of the respective ith feedback channel, Vmod is the spatial common mode estimate, and ki(ΣVni/Σki) is a residual noise suppression estimate of the respective ith feedback channel. ### Claim 8 (depends on 1) The system of claim 1, wherein each respective residual noise suppression estimate is scaled by a respective scaling factor. ### Claim 9 (depends on 1) The system of claim 1, wherein the controller is configured to process the spatial common mode estimate from a center tap from the string of resistors. ### Claim 10 (depends on 1) The system of claim 1, wherein the amplifier comprises a plurality of current conveyors. ### Claim 11 (depends on 1) The system of claim 1, wherein the controller comprises a programmable gain amplifier and an analog-to-digital converter, wherein the analog-to-digital converter is configured to sample an output of the programmable gain amplifier. ### Claim 12 A method, comprising: receiving, by an amplifier, a plurality of processed signals; generating, by a feedback circuit coupled to an output of the amplifier, a plurality of feedback signals, wherein each of the plurality of feedback signals includes a spatial common mode estimate and a residual noise suppression estimate, and wherein generating the plurality of feedback signals comprises: utilizing a switch array for selection of respective feedback signals of the plurality of feedback signals from respective nodes in a string of resistors, wherein resistors of the string of resistors are coupled in series; and processing, by a controller coupled to the feedback circuit, the spatial common mode estimate. ### Claim 13 (depends on 12) The method of claim 12, further comprising: receiving, by a plurality of charge integrators, a plurality of resulting signals from a plurality of capacitive sensor electrodes, wherein each of the plurality of resulting signals comprises a spatial common mode component and a residual noise component; and generating, by the plurality of charge integrators, the plurality of processed signals based at least in part on the plurality of resulting signals. ### Claim 14 (depends on 13) The method of claim 13, wherein the method further comprises receiving, by the plurality of charge integrators, the plurality of feedback signals; and wherein generating the plurality of processed signals comprises mitigating the spatial common mode component and the residual noise components in the plurality of resulting signals using the plurality of feedback signals. ### Claim 15 (depends on 12) The method of claim 12, wherein each of the plurality of feedback signals is weighted by a respective weight value. ### Claim 16 (depends on 15) The method of claim 15, wherein each of the plurality of feedback signals corresponds to a respective feedback channel, and a respective weighted feedback signal for a respective feedback channel is based at least in part on the spatial common mode estimate and a channel-specific residual noise suppression estimate. ### Claim 17 (depends on 15) The method of claim 15, wherein a respective weighted feedback signal for a respective ith feedback channel comprises a respective weighted feedback voltage Vrefi, wherein: Vrefi=Vmod+ki(ΣVni/Σki) where ki is a weight of the respective ith feedback channel, Vmod is the spatial common mode estimate, and ki(ΣVni/Σki) is a residual noise suppression estimate of the respective ith feedback channel. ### Claim 18 A system, comprising: an amplifier configured to receive a plurality of processed signals; a string of resistors coupled to an output of the amplifier, wherein resistors of the string of resistors are coupled in series; a switch array coupled to the string of resistors; and a controller coupled to the string of resistors; wherein the switch array is configured to provide a plurality of feedback signals from nodes in the string of resistors, wherein each of the plurality of feedback signals includes a spatial common mode estimate and a residual noise suppression estimate; and wherein the controller is configured to process the spatial common mode estimate. ### Claim 19 (depends on 18) The system of claim 18, further comprising: a plurality of charge integrators configured to: receive a plurality of resulting signals from a plurality of capacitive sensor electrodes, wherein each of the plurality of resulting signals comprises a spatial common mode component and a residual noise component; and generate the plurality of processed signals based at least in part on the plurality of resulting signals. ### Claim 20 (depends on 19) The system of claim 19, wherein the plurality of charge integrators are further configured to receive the plurality of feedback signals; and wherein generating the plurality of processed signals comprises mitigating the spatial common mode component and the residual noise components in the plurality of resulting signals using the plurality of feedback signals.