# US 10,503,328 B2 · Device and method for generating an electrical power supply in an electronic system with a variable reference potential > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,503,328 B2 - Document ID: US10503328B2 - Status: Granted - Kind: B2 - Application number: 15/489,522 - Filed: 2017-04-17 - Published: 2017-08-03 - Granted: 2019-12-10 - Earliest claimed: 2011-06-16 - Assignees: Quickstep Technologies LLC - Applicants: Quickstep Technologies LLC - Inventors: Christophe Blondin; Christian Neel; Didier Roziere - Web page: https://patentgrep.com/patent/US10503328B2 ## CPC - G06F 3/0416: {Control or interface arrangements specially adapted for digitisers} - G06F 3/044: by capacitive means - H02J 1/08: Three-wire DC power distribution systems; Systems having more than three wires - H02M 7/02: Conversion of AC power input into DC power output without possibility of reversal - H02M 7/06: using discharge tubes without control electrode or semiconductor devices without control electrode - H03K 17/9622: {using a plurality of detectors, e.g. keyboard} - H03K 2217/9607: Capacitive touch switches - H03K 2217/960745: Capacitive differential; e.g. comparison with reference capacitance - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) ## Abstract A method and device for generating a power supply voltage, referenced to a first reference potential, in an electronic system including an energizing source connected to the first and second reference potentials so as to impart an AC voltage differential between the reference potentials, wherein the device includes: (i) a source for supplying AC voltage, which is referenced to the second reference potential, connected to the first reference potential, and encompasses the energizing source; and (ii) rectifying and filtering elements connected, at the input thereof, to the first reference potential and to the source for supplying AC voltage, respectively, so as to generate, at an output, a power supply voltage (Vf) referenced to the first reference potential by rectifying a voltage at the terminals of the source for supplying AC voltage. ## Claims ### Claim 1 An apparatus for touch and proximity detection, comprising: an integrated circuit including: a first electronic system, electrically referenced to a guard potential, configured for capacitively detecting one or more objects at one or more capacitive electrodes; and a second electronic system, distinct from the first electronic system and electrically referenced to a ground potential, and connected to the first electronic system by decoupling circuitry, wherein the ground potential is different from the guard potential; and excitation circuitry connected to the guard and ground potentials so as to impose an AC voltage difference between these potentials, wherein: the decoupling circuitry is configured for communicatively coupling the first electronic system and the second electronic system while maintaining isolation between the guard potential and the ground potential, and the excitation circuitry comprises: an AC voltage supply source referenced to the ground potential and configured for generating an AC voltage; and voltage supply circuitry referenced to the guard potential and configured for receiving the AC voltage from the AC voltage supply source and generating a supply voltage for the first electronic system referenced to the guard potential. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the voltage supply circuitry includes a voltage rectification and filtering circuit coupled between the AC voltage supply source and the second electronic system for generating the supply voltage. ### Claim 3 (depends on 1) The apparatus of claim 1, the AC voltage supply source comprising a first excitation source for generating the AC voltage difference between the guard potential and the ground potential. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the decoupling circuity includes decoupling capacitors coupled between the first electronic system and the second electronic system. ### Claim 5 (depends on 3) The apparatus of claim 3, the AC voltage supply source further comprising a second excitation source for generating the supply voltage. ### Claim 6 (depends on 1) The apparatus of claim 1, the first electronic measurement system comprising one or more electrodes referenced to the guard potential. ### Claim 7 (depends on 6) The apparatus of claim 6, the first electronic measurement system comprising one or more guard electrodes placed in proximity to the one or more electrodes and referenced to the guard potential. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the apparatus is incorporated into a portable computing device. ### Claim 9 (depends on 1) The apparatus of claim 1, further comprising one or more electrodes referenced to the guard potential and configured to shield the first electronic system. ### Claim 10 A method for touch and proximity detection, comprising: referencing a first electronic system to a guard potential; referencing a second electronic system to a ground potential, different than the guard potential, and communicatively coupling the second electronic system to the first electronic system while maintaining isolation between the guard potential and the ground potential; capacitively detecting one or more objects at one or more capacitive electrodes using the first electronic system; and maintaining an AC voltage difference between the guard potential and the ground potential, including: generating an AC voltage referenced to the ground potential; and using the AC voltage to generate a supply voltage for the first electronic system referenced to the guard potential. ### Claim 11 (depends on 10) The method of claim 10, further comprising voltage rectifying and filtering the AC voltage to generate the supply voltage. ### Claim 12 (depends on 10) The method of claim 10, further comprising generating the AC voltage difference between the guard potential and the ground potential using a first excitation source. ### Claim 13 (depends on 10) The method of claim 10, further comprising decoupling electrical connections between the first electronic system and the second electronic system. ### Claim 14 (depends on 12) The method of claim 12, further comprising generating the power supply voltage using a second excitation source. ### Claim 15 (depends on 10) The method of claim 10, further comprising performing touch and proximity detection using one or more electrodes referenced to the guard potential. ### Claim 16 (depends on 15) The method of claim 15, further comprising placing one or more guard electrodes in proximity to the one or more electrodes and referencing the one or more guard electrodes to the guard potential.