# US 12,769,405 B1 · System and method for capacitive split contactless keyboard stack with capacitive encoding to identify among a plurality of removable tactile input layers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,769,405 B1 - Document ID: US12769405B1 - Status: Granted - Kind: B1 - Application number: 19/275,466 - Filed: 2025-07-21 - Granted: 2026-10-20 - Earliest claimed: 2025-07-21 - Assignees: Dell Products L.P. - Applicants: Dell Products LP - Inventors: Rachid M. Alameh; Jason Scott Morrison; Brandon Joel Brocklesby - Web page: https://patentgrep.com/patent/US12769405B1 ## CPC - G06F 3/0238: {Programmable keyboards (key guide holders G06F3/0224)} - G06F 3/0202: {Constructional details or processes of manufacture of the input device} - G06F 2203/04107: Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds - G06F 2203/04108: Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract An information handling system having a split keyboard structure with a keyboard sensing hardware structure formed under a sealed input surface with a hardware processor, a data storage device, and a power management unit formed into a keyboard chassis. The keyboard sensing hardware structure includes capacitive pad sensors operably coupled to a capacitive sensor microprocessor to detect capacitive changes from user interaction with one of a plurality of removable tactile input layers installed above the sealed input surface. The capacitive sensor microprocessor executes machine readable code instructions of a dynamic key mapping engine to detect, via the capacitive pad sensors, capacitive encoding for determining a first removable tactile input layer that is installed from among the plurality of removable tactile input layers via detection of cumulative capacitance or a first set of conductive material portions formed with a plurality of keyboard keys having a unique layout, number, or arrangement. ## Claims ### Claim 1 A split keyboard structure of an information handling system having a keyboard sensing hardware structure formed under a sealed input surface of a keyboard chassis comprising: a hardware processor, a data storage device, and a power management unit (PMU) formed into a keyboard chassis to provide power to the hardware processor and data storage device; the keyboard sensing hardware structure including a plurality of capacitive pad sensors in a capacitive pads layer formed under the sealed input surface as a top surface of the keyboard chassis, wherein the capacitive pads layer formed under a sealed input surface is operably coupled to a capacitive sensor microprocessor to detect capacitive changes from user interaction with one of a plurality of removable tactile input layers installed above the sealed input surface; and the capacitive sensor microprocessor to execute machine readable code instructions of a dynamic key mapping engine to detect, via the capacitive pad sensors, capacitive encoding for a first removable tactile input layer from among the plurality of removable tactile input layers that is operatively coupled on top of the sealed input surface via detection of a first set of conductive material portions formed with a plurality of keyboard keys of the first removable tactile input layer, wherein the capacitive encoding from the first set of conductive material portions formed with a plurality of keyboard keys of the first removable tactile input layer has a unique layout, number, or arrangement of sets of conductive material portions relative to other removable tactile input layers in the plurality of removable tactile input layers installable onto the sealed input layer. ### Claim 2 (depends on 1) The split keyboard structure of the information handling system of claim 1, wherein: the sets of conductive material are formed under plural keyboard key caps of each of the plurality of removable tactile input layers; the capacitive sensor microprocessor, via the capacitive pad sensors, measures a cumulative capacitance at each of the capacitive pad sensors; and the capacitive sensor microprocessor executes machine readable code instructions of a dynamic key mapping engine to access a tactile input layer capacitance look-up table to, with the detected cumulative capacitance, identify that the first removable tactile input layer from among the plurality of removable tactile input layers is operatively coupled to the sealed input surface. ### Claim 3 (depends on 1) The split keyboard structure of the information handling system of claim 1, wherein: the sets of conductive material are formed under plural keyboard key caps or around the periphery of each of the plurality of removable tactile input layers; the capacitive sensor microprocessor, via the capacitive pad sensors, measures a capacitance at each of the capacitive pad sensors to determine which keyboard keys includes the conductive material to identify locations of the first set conductive material portions for the capacitance encoding of the installed first removable tactile input layer; and the capacitive sensor microprocessor executes machine readable code instructions of a dynamic key mapping engine to access a tactile input layer capacitance look-up table to, with the detected locations of keyboard keys that include the conductive material portions, identify that the first removable tactile input layer from among the plurality of removable tactile input layers is operatively coupled to the sealed input surface. ### Claim 4 (depends on 1) The split keyboard structure of the information handling system of claim 1, wherein each of the plurality of removable tactile input layers is removably coupled to the sealed input surface via a latch structure or magnet to provide for removal of the first removable tactile input layer from the sealed input surface of the keyboard sensing hardware structure. ### Claim 5 (depends on 1) The split keyboard structure of the information handling system of claim 1, wherein the first removable tactile input layer of the plurality of removable tactile input layers includes a first set of keyboard keys with a first plurality of keys and popples forming a first type of keyboard layout that is removably coupled to the sealed input surface via an interference fit and a second removable tactile input layer of the plurality of removable tactile input layers includes a second set of keyboard keys with a second plurality of keys and popples forming a second type of keyboard layout different from the first type of keyboard layout that is removably coupled to the sealed input surface via the interference fit when the first removable tactile input layer is removed. ### Claim 6 (depends on 1) The split keyboard structure of the information handling system of claim 1 further comprising: the capacitive sensor microprocessor executing the machine readable code instructions of the dynamic key mapping engine configured to dynamically assign keyboard functions to specific pad sensor locations based on defined keyboard layouts for the first removable tactile input layer having a first type of keyboard layout based on identification of the first removable tactile input layer with the detected capacitive encoding from the first set of conducive material portions. ### Claim 7 (depends on 1) The split keyboard structure of the information handling system of claim 1 further comprising: the capacitive sensor microprocessor executing machine readable code instructions of a capacitive sensor driver operatively coupled to the capacitive pads layer to receive input from the plurality of capacitive pad sensors as detected changes in capacitance levels without physical contact by the user or by a key under the sealed input surface of the keyboard chassis, wherein the capacitive pad sensors are carbon-based conductive deposits. ### Claim 8 (depends on 1) The split keyboard structure of the information handling system of claim 1, wherein the plurality of removable tactile input layers each include a set of mechanical keyboard keys and each of the plurality of removable tactile input layers are removably coupled to the sealed input surface via an interference fit to provide for removal of each of the plurality of removable tactile input layers from the sealed input surface of the keyboard sensing hardware structure. ### Claim 9 (depends on 1) The split keyboard structure of the information handling system of claim 1, wherein the active shielding layer is operatively coupled to a voltage source to actively drive a plurality of shielding pads to prevent electric fields at the capacitive sensor pads from being parasitically capacitively grounded by the grounding layer and increase capacitive sensing sensitivity of the capacitive sensor pads. ### Claim 10 An information handling system executing machine readable code instructions to detect user keyboard input and touch input at a split keyboard structure of the information handling system comprising: a hardware processor, a data storage device, and a power management unit (PMU) to provide power to the hardware processor and data storage device formed into a base chassis of the information handling system; a keyboard sensing hardware structure formed under a sealed input surface of the base chassis of the information handling system including a plurality of capacitive pad sensors in a capacitive pads layer formed under the sealed input surface, a grounding layer, and an active shielding layer between the capacitive pad sensors and the grounding layer; the capacitive pads layer formed under a sealed input surface operably coupled to a capacitive sensor microprocessor to detect capacitive changes from user interaction with one of a plurality of removable tactile input layers installed above the sealed input surface; and the capacitive sensor microprocessor to execute machine readable code instructions of a dynamic key mapping engine to detect, via one or more of the capacitive pad sensors, which of the plurality of removable tactile input layers is operatively coupled to the sealed input surface via detection of at least one set of conductive material portions formed into the removable tactile layers, wherein the conductive material portions are formed under plural keyboard keys of each of the plurality of removable tactile input layers and wherein the capacitive sensor microprocessor, via the capacitive pad sensors, measures a capacitance at each of the capacitive pad sensors to determine a capacitance encoding to determine which of the plurality of removable tactile input layers is installed onto the sealed input surface of the base chassis. ### Claim 11 (depends on 10) The information handling system of claim 10, wherein the capacitive sensor microprocessor executes machine readable code instructions of a dynamic key mapping engine to access a tactile input layer capacitance look-up table to, with the detected cumulative capacitance across all capacitive pad sensors, identify the capacitive encoding for which of the plurality of removable tactile input layers is operatively coupled to the sealed input surface. ### Claim 12 (depends on 10) The information handling system of claim 10, wherein the capacitive sensor microprocessor executes machine readable code instructions of a dynamic key mapping engine to access a tactile input layer capacitance look-up table to, with the detected capacitance at particular capacitive pad sensors having identified locations in the capacitive pads layer, identify the capacitive encoding for which of the plurality of removable tactile input layers is operatively coupled to the sealed input surface. ### Claim 13 (depends on 10) The information handling system of claim 10, wherein each of the plurality of removable tactile input layers is removably coupled to the sealed input surface via a latch structure to provide for removal of the first removable tactile input layer from the sealed input surface of the keyboard sensing hardware structure. ### Claim 14 (depends on 10) The information handling system of claim 10, wherein a first removable tactile input layer of the plurality of removable tactile input layers including a first set of keyboard keys with a first plurality of keys and popples forming a first type of keyboard layout is removably coupled to the sealed input surface via an interference fit and a second removable tactile input layer of the plurality of removable tactile input layers including a second set of keyboard keys with a second plurality of keys and popples removably forming a second type of keyboard layout different from the first type of keyboard layout is operatively coupled to the sealed input surface via the interference fit upon removal of the first removable tactile input layer. ### Claim 15 (depends on 10) The information handling system of claim 10 further comprising: the capacitive sensor microprocessor executing the machine readable code instructions of the dynamic key mapping engine configured to dynamically assign keyboard functions to specific pad sensor locations based on defined keyboard layouts for the removable tactile input layer identified as installed onto the sealed input surface of the base chassis from the detected capacitive encoding. ### Claim 16 An information handling system including a split keyboard structure to detect user keyboard input, touch input, and touchless gesture input at the information handling system comprising: a hardware processor, a data storage device, and a power management unit (PMU) to provide power to the hardware processor and data storage device formed into a base chassis of the information handling system; a keyboard sensing hardware structure formed under a sealed input surface that is a top surface of the base chassis housing for the information handling system including a plurality of capacitive pad sensors in a capacitive pads layer formed under the sealed input surface, a grounding layer, and an active shielding layer between the capacitive pad sensors and the grounding layer, wherein the capacitive pads layer formed under a sealed input surface is operably coupled to a capacitive sensor microprocessor to detect capacitive changes from user interaction with one of a plurality of removable tactile input layers above the sealed input surface; and the capacitive sensor microprocessor to execute machine readable code instructions of a dynamic key mapping engine to detect, via the capacitive pad sensors, that a first removable tactile input layer among the plurality of removable tactile input layers is operatively coupled to the sealed input surface via cumulative capacitance of a first keyboard key layout of the first removable tactile input layer with the capacitive sensor microprocessor, via the capacitive pad sensors, measuring the cumulative capacitance to determine a capacitive encoding level for the first keyboard layout of a first set of keyboard keys that is unique relative to the remaining keyboard layouts of other removable tactile input layers of the plurality of tactile input layers installable onto the sealed input surface, wherein the capacitive sensor microprocessor accesses a tactile input layer capacitance look-up table to, with the cumulative capacitance of the first keyboard layout, identify that the first removable tactile input layer among the plurality of removable tactile input layers is operatively coupled to the sealed input surface. ### Claim 17 (depends on 16) The information handling system of claim 16, wherein each of the plurality of removable tactile input layers includes a unique set conductive material portions, wherein the conductive material portions are formed under one or more keyboard keys of each of the plurality of removable tactile input layers. ### Claim 18 (depends on 16) The information handling system of claim 16 further comprising: the first removable tactile input layer of the plurality of removable tactile input layers includes the first set of keyboard keys with a first plurality of keycaps and popples forming the first keyboard layout that is removably coupled to the sealed input surface via an interference fit; and a second removable tactile input layer of the plurality of removable tactile input layers includes a second set of keyboard keys with a second plurality of keycaps and popples forming a second keyboard layout different from the first keyboard layout and having a second cumulative capacitance that is a different capacitive encoding level than the first removable tactile input layer; wherein the second removable tactile input layer is removably coupled to the sealed input surface via the interference fit when the first removable tactile input layer is removed. ### Claim 19 (depends on 16) The information handling system of claim 16 further comprising: the capacitive sensor microprocessor executing the machine readable code instructions of the dynamic key mapping engine configured to dynamically assign keyboard functions to specific pad sensor locations based on defined keyboard layouts corresponding to the first keyboard layout for the first removable tactile input layer based on the detected capacitive encoding level for the first keyboard layout of the first removable tactile input layer. ### Claim 20 (depends on 16) The information handling system of claim 16, wherein the plurality of removable tactile input layers each include mechanical keyboard keys and each of the plurality of removable tactile input layers are removably coupled to the sealed input surface via a magnetic coupling to provide for installation and removal of each of the plurality of removable tactile input layers from the sealed input surface of the keyboard chassis with the keyboard sensing hardware structure formed thereunder.