# US 12,602,122 B2 · Information handling system touch detection device grounding and self-test > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,602,122 B2 - Document ID: US12602122B2 - Status: Granted - Kind: B2 - Application number: 18/224,655 - Filed: 2023-07-21 - Published: 2025-01-23 - Granted: 2026-04-14 - Earliest claimed: 2023-07-21 - Assignees: Dell Products L.P. - Applicants: Dell Products L.P. - Inventors: Wu Chin-Chung; Che-Jung Chang; Yueh-Ching Lu; Yong-Teng Lin - Web page: https://patentgrep.com/patent/US12602122B2 ## CPC - G06F 3/038: Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry - G06F 3/03547: {Touch pads, in which fingers can move on a surface} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract An information handling system includes a touchpad that accepts touch inputs to move a cursor on a display and that deflects at a front side to accept button inputs. A bracket is disposed between a touch detection surface and circuit board of the touchpad to bias the touch detection surface up and deflect in response to a push down as a button input. Conical spring ground devices coupled to the circuit board on opposing sides of the bracket interface with an ohmmeter included on the circuit board that detects a resistance from a first ground device through the system ground to a second ground device. Resistance across ground is applied by the touchpad processor to adjust touch detection sensitivity and avoid ghost inputs. ## Claims ### Claim 1 An information handling system comprising: a housing; a processor coupled in the housing and operable to execute instructions to process information; a memory coupled in the housing and interfaced with the processor, the memory operable to store the instructions and information; a touch detection surface coupled to the housing and interfaced with the processor, the touch detection surface interfaced with a circuit board having a processing resource, the circuit board grounded to the housing at opposing sides; an ohmmeter circuit coupled to the circuit board and interfaced with the processing resource, the ohmmeter circuit configured to measure resistance between the grounds at the opposing sides through the housing. ### Claim 2 (depends on 1) The information handling system of claim 1 wherein the touch detection surface further comprises: a bracket coupled to the housing at the opposing sides and disposed between the touch detection surface and the circuit board; wherein the touch detection surface accepts button presses by deflection of the bracket from a press at the touch detection surface. ### Claim 3 (depends on 2) The information handling system of claim 2 further comprising: a first spring biased from the circuit board at a first side and aligned against a first position of the housing, the first spring interfaced with ground of the circuit board; and a second spring biased from the circuit board at a second side and aligned against a second position of the housing, the second spring interfaced with ground of the circuit board. ### Claim 4 (depends on 3) The information handling system of claim 3 wherein the first and second springs comprise conical springs of conductive material. ### Claim 5 (depends on 4) The information handling system of claim 4 wherein the touch detection surface comprises a capacitive touch detection surface. ### Claim 6 (depends on 1) The information handling system of claim 1 wherein the processing resource applies the resistance to adjust sensitivity of the touch detection surface. ### Claim 7 (depends on 6) The information handling system of claim 6 wherein the ohmmeter circuit integrates within the processing resource. ### Claim 8 (depends on 7) The information handling system of claim 7 further comprising: a first spring biased from the circuit board at a first side and aligned against a first side of a bracket disposed between the touch detection surface and the circuit board, the bracket coupled to the housing, the first spring interfaced with ground of the circuit board; and a second spring biased from the circuit board at a second side of the bracket and aligned against a second side of the bracket, the second spring interfaced with ground of the circuit board. ### Claim 9 A method for managing touch inputs at a touchpad integrated in a portable information handling system, the method comprising: grounding the touchpad at a first side with a first ground device interfaced with a housing of the information handling system; grounding the touchpad at a second side with a second ground device interfaced with the housing of the information handling system; measuring at the touchpad a resistance from the first ground device through the housing to the second ground device; detecting touches at a touch detection surface of the touchpad with a processing resource interfaced with the touch detection surface; applying the measured resistance with the processing resource to adjust a sensitivity of the touchpad touch detection surface. ### Claim 10 (depends on 9) The method of claim 9 wherein the measuring a resistance is performed with an ohmmeter integrated in the processing resource. ### Claim 11 (depends on 9) The method of claim 9 further comprising: coupling a bracket to the housing between the touch detection surface and a circuit board having the processing resource; and grounding the touchpad at the first and second sides to contact a housing of the information handling system to first and second grounding devices coupled to the circuit board. ### Claim 12 (depends on 11) The method of claim 11 wherein the ground devices comprise conical springs coupled to the circuit board. ### Claim 13 (depends on 12) The method of claim 12 further comprising: pressing down on a front side of the touch detection surface to deflect the bracket; and in response to deflection of the bracket, applying a button press input. ### Claim 14 (depends on 13) The method of claim 13 wherein the touch detection surface comprises a capacitive touch detection surface.