# US 12,603,247 B2 · Transition control in a bias supply > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,603,247 B2 - Document ID: US12603247B2 - Status: Granted - Kind: B2 - Application number: 18/656,543 - Filed: 2024-05-06 - Published: 2024-12-26 - Granted: 2026-04-14 - Earliest claimed: 2022-09-01 - Assignees: Advanced Energy Industries, Inc. - Applicants: Advanced Energy Industries, Inc. - Inventors: Hien Minh Nguyen - Web page: https://patentgrep.com/patent/US12603247B2 ## CPC - H01J 37/32146: {Amplitude modulation, includes pulsing} - H03K 3/017: Adjustment of width or dutycycle of pulses (pulse width modulation H03K7/08 {; to maintain energy constant H03K3/015}) - H01J 2237/334: Etching - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) - 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 Bias supplies and bias control methods are disclosed. One method comprises applying an asymmetric periodic voltage waveform and providing a corresponding current waveform at an output node relative to a return node; receiving a signal to change from a current state of the asymmetric periodic voltage waveform to a next state of the asymmetric periodic voltage waveform; and adjusting, during a transition from the current state to the next state, at least one portion of the asymmetric periodic voltage waveform and simultaneously adjusting a fundamental frequency of the asymmetric periodic voltage waveform to settle at the next state. ## Claims ### Claim 1 A bias supply to apply a periodic voltage comprising: a switch network and at least one power supply, the switch network and the at least one power supply configured, in combination, to apply a periodic voltage waveform at a first node; and a controller configured to: receive a signal to change from a present state to a next state; and adjust, during a transition from the present state to the next state, a voltage of the at least one power supply and simultaneously control a switching frequency of the switch network to settle at the next state after a transition wherein the controller is configured to adjust the frequency according to a predefined transition time using a predefined transition type. ### Claim 2 (depends on 1) The bias supply of claim 1, wherein the controller comprises a lookup table to access waveform timing parameter values and a corresponding number of pulse width modulated cycles for each timing parameter value. ### Claim 3 (depends on 1) The bias supply of claim 1, wherein the controller comprises a feedback control loop to adjust the frequency of the periodic voltage waveform during the transition. ### Claim 4 (depends on 3) The bias supply of claim 3, wherein the feedback control loop utilizes a bang-bang control scheme. ### Claim 5 (depends on 3) The bias supply of claim 3, wherein the feedback control loop utilizes a proportional-integral-derivative control scheme. ### Claim 6 (depends on 1) The bias supply of claim 1, wherein the controller is configured to adjust the at least one power supply and the switching frequency of the switch network according to a transition type selected from the group consisting of a linear current ramp transition, an exponentially-decaying current transition, and a concave-parabolic current transition, intentional-overshoot transition type, and intentional-undershoot transition types. ### Claim 7 A method for applying a periodic voltage comprising: applying a periodic voltage waveform; receiving a signal to change from a present state of the periodic voltage waveform to a next state of the periodic voltage waveform; and adjusting, during a transition from the present state to the next state, at least one portion of the periodic voltage waveform and simultaneously adjusting a frequency of the periodic voltage waveform to settle at the next state after a transition, wherein the adjusting comprises adjusting the frequency according to a predefined transition time using a predefined transition type. ### Claim 8 (depends on 7) The method of claim 7 wherein the adjusting comprises accessing a lookup table to access waveform timing parameter values and a corresponding number of pulse width modulated cycles for each timing parameter value. ### Claim 9 (depends on 7) The method of claim 7, wherein the adjusting comprises utilizing a feedback control loop to adjust the frequency. ### Claim 10 (depends on 9) The method of claim 9, wherein the feedback control loop utilizes a bang-bang control scheme. ### Claim 11 (depends on 9) The method of claim 9, wherein the feedback control loop utilizes a proportional-integral-derivative control scheme. ### Claim 12 (depends on 7) The method of claim 7, wherein the adjusting comprising adjusting the frequency according to a transition type selected from the group consisting of a linear current ramp transition, an exponentially-decaying current transition, and a concave-parabolic current transition, intentional-overshoot transition type, and intentional-undershoot transition types. ### Claim 13 A non-transitory medium encoded with instructions that are executable by a processor and/or are readable by a field programmable gate array, the instructions comprising instructions to: cause a bias supply to apply a periodic voltage waveform; process a signal to change from a present state of the periodic voltage waveform to a next state of the periodic voltage waveform; and cause the bias supply to adjust, during a transition from the present state to the next state, at least one portion of the periodic voltage waveform and simultaneously adjust a frequency of the periodic voltage waveform to settle at the next state, wherein the frequency during the transition is different than the frequency during either the present state or the next state. ### Claim 14 (depends on 13) The non-transitory medium of claim 13, wherein the instructions comprise instructions to: access a lookup table to access waveform timing parameter values and a corresponding number of pulse width modulated cycles for each timing parameter value to adjust the frequency. ### Claim 15 (depends on 13) The non-transitory medium of claim 13, wherein the instructions comprise instructions to adjust the frequency of the periodic voltage waveform during the transition with a feedback control loop. ### Claim 16 (depends on 15) The non-transitory medium of claim 15, wherein the feedback control loop utilizes a bang-bang control scheme. ### Claim 17 (depends on 15) The non-transitory medium of claim 15, wherein the feedback control loop utilizes a proportional-integral-derivative control scheme.