# US 12,191,131 B2 · Ultra low noise floated high voltage supply for mass spectrometer ion detector > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,191,131 B2 - Document ID: US12191131B2 - Status: Granted - Kind: B2 - Application number: 17/762,247 - Filed: 2020-09-24 - Published: 2022-12-01 - Granted: 2025-01-07 - Earliest claimed: 2019-09-24 - Assignees: DH Technologies Development Pte. Ltd. - Applicants: DH Technologies Development PTE. LTD. - Inventors: Manuel Faur; Ernesto Gradin - Web page: https://patentgrep.com/patent/US12191131B2 ## CPC - H01J 49/022: {Circuit arrangements, e.g. for generating deviation currents or voltages (regulating electric or magnetic variables in general, e.g. current, magnetic field G05F); Components associated with high voltage supply (high voltage supply per se H02M)} - H01J 49/025: {Detectors specially adapted to particle spectrometers (data acquisition H01J49/0036; detectors per se G01T, e.g. G01T1/28, G01T1/29)} - H02M 1/14: Arrangements for reducing ripples from DC input or output - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) - 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) ## Abstract A high-voltage power supply system for a mass spectrometer comprises a ground-referenced power supply with a first transformer having a primary winding and a secondary winding, the primary winding is electrically coupled to a first source of AC power, and a floated bias voltage power supply with a second transformer having a primary winding and a secondary winding, the primary winding of the second transformer is electrically coupled to a second source of AC power. A return electrical path of the floated bias voltage power supply is electrically coupled to the ground-referenced power supply to bias an output voltage of the ground-referenced power supply. A floating shield is around the floating bias voltage power supply, and at least one resistive element is in the return electrical path of the floated bias voltage power supply to reduce noise coupled from the floated bias voltage power supply to the ground-referenced power supply. ## Claims ### Claim 1 A high-voltage power supply system for use in a mass spectrometer, comprising: a ground-referenced power supply having a first transformer comprising a primary winding and a secondary winding, said primary winding being electrically coupled to a first source of AC power, a floated bias voltage power supply having a second transformer comprising a primary winding and a secondary winding, said primary winding of said second transformer being electrically coupled to a second source of AC power, wherein a return electrical path of said floated bias voltage power supply is electrically coupled to said ground-referenced power supply so as to bias an output voltage of said ground-referenced power supply, a floating shield disposed around said floated bias voltage power supply, and at least one resistive element disposed in said return electrical path of said floated bias voltage power supply to reduce noise coupled from said floated bias voltage power supply to said ground-referenced power supply. ### Claim 2 (depends on 1) The high-voltage power supply system of claim 1, wherein said floating shield provides a low AC impedance path from said return electrical path of said floated bias voltage power supply to the ground. ### Claim 3 (depends on 2) The high-voltage power supply system of claim 2, wherein said at least one resistive element is coupled in series with a capacitance associated with said floating shield so as to enhance impedance of said return electrical path. ### Claim 4 (depends on 3) The high-voltage power supply system of claim 3, wherein said at least one resistive element has a resistance in a range of about 10 kΩ to about 1 MΩ. ### Claim 5 (depends on 4) The high-voltage power supply system of claim 4, wherein said at least one resistive element has a resistance in a range of about 100 kΩ to about 1 MΩ. ### Claim 6 (depends on 3) The high-voltage power supply system of claim 3, wherein said capacitance associated with said floating shield is in a range of about 6 pF to about 100 nF. ### Claim 7 (depends on 6) The high-voltage power supply system of claim 6, wherein said capacitance associated with said floating shield is in a range of about 100 pF to about 50 nF. ### Claim 8 (depends on 1) The high-voltage power supply system of claim 1, further comprising a Faraday shield disposed in said second transformer so as to reduce parasitic coupling between the secondary winding and the primary winding of said second transformer. ### Claim 9 (depends on 8) The high-voltage power supply system of claim 8, wherein said Faraday shield reduces said coupling by at least about 2 pF. ### Claim 10 (depends on 8) The high-voltage power supply system of claim 8, wherein said Faraday shield reduces said coupling by a factor in a range of about 2 to about 100. ### Claim 11 (depends on 1) The high-voltage power supply system of claim 1, wherein said return electrical path is capacitively coupled to the ground via at least one capacitor. ### Claim 12 (depends on 1) The high-voltage power supply system of claim 1, wherein said ground-referenced power supply provides an output voltage in a range of about 0 to about 20 kV. ### Claim 13 (depends on 10) The high-voltage power supply system of claim 10, wherein said floated bias voltage power supply provides a bias voltage in a range of about 0 to about 10 kV. ### Claim 14 (depends on 1) The high-voltage power supply system of claim 1, wherein said floated bias voltage power supply is coupled to an ion detector of said mass spectrometer to apply a bias voltage thereto. ### Claim 15 A mass spectrometer, comprising: a mass analyzer, an ion detector disposed downstream of said mass analyzer, and a high-voltage power supply system configured to apply a high voltage to said ion detector, wherein said high-voltage power supply system comprises: a ground-referenced power supply having a first transformer comprising a primary winding and a secondary winding, said primary winding being electrically coupled to a first source of AC power, a floated bias voltage power supply having a second transformer comprising a primary winding and a secondary winding, said primary winding of said second transformer being electrically coupled to a second source of AC power, wherein a return electrical path of said floated bias voltage power supply is electrically coupled to said ground-referenced power supply so as to bias an output voltage of said ground-referenced power supply, a floating shield disposed around said floating bias power supply, and at least one resistive element disposed in said return electrical path of said floated bias voltage power supply to reduce noise coupled from said floated bias voltage power supply to said ground-referenced power supply. ### Claim 16 (depends on 15) The mass spectrometer of claim 15, wherein said floating shield provides a low AC impedance path from said return electrical path of said floated bias voltage power supply to the ground. ### Claim 17 (depends on 15) The mass spectrometer of claim 15, wherein said at least one resistive element is coupled in series with a capacitance associated with said floating shield so as to enhance impedance of said return electrical path. ### Claim 18 (depends on 17) The mass spectrometer of claim 17, wherein said at least one resistive element has a resistance in a range of about 10 kΩ to about 1 MΩ. ### Claim 19 (depends on 18) The mass spectrometer of claim 18, wherein said capacitance associated with said floating shield is in a range of about 6 pF to about 100 nF. ### Claim 20 (depends on 15) The mass spectrometer of claim 15, wherein said return electrical path is capacitively coupled to the ground via at least one capacitor.