Prosecution Insights
Last updated: April 19, 2026
Application No. 18/574,437

POWER CONVERSION DEVICE HAVING MULTI-LEVEL STRUCTURE

Non-Final OA §103§112
Filed
Dec 27, 2023
Examiner
TRAN, NGUYEN
Art Unit
2838
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
LG Innotek Co., Ltd.
OA Round
1 (Non-Final)
83%
Grant Probability
Favorable
1-2
OA Rounds
2y 6m
To Grant
91%
With Interview

Examiner Intelligence

Grants 83% — above average
83%
Career Allow Rate
895 granted / 1073 resolved
+15.4% vs TC avg
Moderate +8% lift
Without
With
+7.6%
Interview Lift
resolved cases with interview
Typical timeline
2y 6m
Avg Prosecution
36 currently pending
Career history
1109
Total Applications
across all art units

Statute-Specific Performance

§101
0.3%
-39.7% vs TC avg
§103
51.6%
+11.6% vs TC avg
§102
33.9%
-6.1% vs TC avg
§112
10.7%
-29.3% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1073 resolved cases

Office Action

§103 §112
DETAILED ACTION 1. This action is in response to the election filed on 11/12/25 The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . Election/Restrictions 2. Applicant’s election without traverse of Species 3 (figures 8, 10-12, and 14) in the reply filed on 11/12/25 is acknowledged. Drawings 3. The drawings are objected to under 37 CFR 1.83(a). The drawings must show every feature of the invention specified in the claims. Therefore, “connected in parallel through a switching element” (in claim 6) must be shown or the feature(s) canceled from the claim(s). No new matter should be entered. Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance. Specification 4. The specification is objected to as failing to provide proper antecedent basis for the claimed subject matter. See 37 CFR 1.75(d)(1) and MPEP § 608.01(o). Correction of the following is required: Claims 1, 10, and 12 the limitation recites “and output same”. There is insufficient antecedent basis for this limitation in the claim. Claim Rejections - 35 USC § 112 5. The following is a quotation of 35 U.S.C. 112(b): (b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention. The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph: The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention. 6. Claim 1 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. Claims 1, 10, and 12 the limitation recites “and output same”. Also, it is unclear to what being output and what being output same? Claim Rejections - 35 USC § 103 7. The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. 8. Claims 1-8, 12-17, and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Zushi et al. (US 20220001750) in view of Canales et al. (US 20170126010). Regarding claim 1: Zushi et al. disclose (i.e. figure 5) a power conversion device comprising: a plurality of converters (i.e. 21 and 22) respectively connected to a plurality of cell strings (i.e. Solar cell module); and an auxiliary power supply unit (i.e. 12) configured to supply driving power to each of the plurality of converters (i.e. 21 and 22), and wherein the plurality of converters (i.e. 21 and 22) constitutes a multi-level structure (i.e. series configuration of converters 21, 22), but does not specifically disclose the auxiliary power supply unit comprises: a first voltage conversion part configured to convert a first voltage of at least one output terminal from among output terminals of the plurality of cell strings into a second voltage, and output same; and a second voltage conversion part configured to convert the second voltage, outputted from the first voltage conversion part, into a third voltage and supply driving power to each of the plurality of converters Canales et al. disclose the auxiliary power supply unit (i.e. figure 1) comprises: a first voltage conversion part (i.e. 24, 26) configured to convert a first voltage (i.e. from 12) of at least one output terminal from among output terminals of the plurality of cell strings (i.e. 12, ¶ 21-22) into a second voltage (i.e. from 26), and output same (i.e. same from 12, 26); and a second voltage conversion part (i.e. 28) configured to convert the second voltage (i.e. from 26), outputted from the first voltage conversion part (i.e. 24, 26), into a third voltage (i.e. from 28) and supply driving power to each of the plurality of converters (i.e. 22) (i.e. in addition, the converter 22 are connected in series. Therefore, the converter 18 may supply driving power to each converter via one another). Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention with the supply as disclose by Canales et al. in order to supply driving power to each of the plurality of converters, because it enhances the efficiency of such a power station and to optimize control of the converters of such a power station. Regarding claims 2 and 13: Zushi et al. disclose the limitation of the claim(s) as discussed above, but does not specifically disclose the first voltage conversion part outputs a different level of the second voltage depending on a range of the first voltage. Canales et al. disclose supply unit (i.e. figure 1) comprises the first voltage (i.e. 24, 26) conversion part outputs a different level of the second voltage (i.e. from 26) depending on a range of the first voltage (i.e. from 12). Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention with the supply as disclose by Canales et al., because it enhances the efficiency of such a power station and to optimize control of the converters of such a power station. Regarding claims 3 and 14: Zushi et al. disclose the limitation of the claim(s) as discussed above, but does not specifically disclose the first voltage conversion part comprises at least one of a step- down regulator, a step-up regulator, and a step-up and step-down regulator. Canales et al. disclose supply unit (i.e. figure 1) comprises the first voltage (i.e. 24, 26) conversion part comprises at least one of a step-down regulator, a step-up regulator, and a step-up and step-down regulator (i.e. function of the converter) (¶ 73). Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention with the supply as disclose by Canales et al., because it enhances the efficiency of such a power station and to optimize control of the converters of such a power station. Regarding claims 4 and 15: Zushi et al. disclose the limitation of the claim(s) as discussed above, but does not specifically disclose the first voltage conversion part comprises at least one of a buck converter, a linear regulator, a boost converter, a charge pump, and a buck-boost converter. Canales et al. disclose supply unit (i.e. figure 1) comprises the non-isolated DC-to-DC converter may be a buck, boost or buck/boost converter (i.e. ¶ 73). Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention with the supply as disclose by Canales et al. to have the first voltage conversion part comprises at least one of a step- down regulator, a step-up regulator, and a step-up and step-down regulator, because it enhances the efficiency of such a power station and to optimize control of the converters of such a power station. Regarding claims 5 and 16: Zushi et al. disclsoes (i.e. figure 5) the first voltage conversion part (i.e. conversion part of 22) supplies power to a device (i.e. device include battery 2) operating at the second voltage (i.e. from 12). Regarding claims 6 and 17: Zushi et al. disclose the limitation of the claim(s) as discussed above, but does not specifically disclose the first voltage conversion part, each output terminal of the plurality of cell strings is connected in parallel through a switching element. Canales et al. disclose supply unit (i.e. figure 1) comprises the first voltage conversion part, each output terminal of the plurality of cell strings (i.e. 12, ¶ 21-22) is connected in parallel through a switching element (i.e. 30). Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention with the supply as disclose by Canales et al., because it enhances the efficiency of such a power station and to optimize control of the converters of such a power station. Regarding claims 8 and 19: Zushi et al. disclose (i.e. figure 5) the power converter (i.e. 12) operates by receiving an enable signal (i.e. from 43), but does not specifically disclose the second voltage conversion part operates by receiving an enable signal. Canales et al. disclose supply unit (i.e. figure 1) comprises the second voltage conversion part (i.e. 28) operates by receiving an enable signal (i.e. signal from the control to drive the conversion part 28). Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention with the supply as disclose by Canales et al. to have the second voltage conversion part operates by receiving an enable signal, because it enhances the efficiency of such a power station and to optimize control of the converters of such a power station. Regarding claim 12: Zushi et al. discloses (i.e. figure 5) a solar module comprising: a plurality of cell strings (i.e. Solar cell module) each comprising one or more solar cells; a plurality of converters (i.e. 21 and 22) respectively connected to the plurality of cell strings (i.e. Solar cell module); and an auxiliary power supply unit (i.e. 12) configured to supply driving power to each of the plurality of converters (i.e. 21 and 22) using voltages outputted from the each of the plurality of cell strings (i.e. Solar cell module), wherein the plurality of converters constitutes a multi-level structure (i.e. series configuration of converters 21, 22). but does not specifically disclose the auxiliary power supply unit comprises: a first voltage conversion part configured to convert a first voltage of at least one output terminal from among output terminals of the plurality of cell strings into a second voltage, and output same; and a second voltage conversion part configured to convert the second voltage, outputted from the first voltage conversion part, into a third voltage and supply driving power to each of the plurality of converters. Canales et al. disclose the auxiliary power supply unit (i.e. figure 1) comprises: a first voltage conversion part (i.e. 24, 26) configured to convert a first voltage (i.e. from 12) of at least one output terminal from among output terminals of the plurality of cell strings (i.e. 12, ¶ 21-22) into a second voltage (i.e. from 26), and output same (i.e. same from 12, 26); and a second voltage conversion part (i.e. 28) configured to convert the second voltage (i.e. from 26), outputted from the first voltage conversion part (i.e. 24, 26), into a third voltage (i.e. from 28) and supply driving power to each of the plurality of converters (i.e. 22) (i.e. in addition, the converter 22 are connected in series. Therefore, the converter 18 may supply driving power to each converter via one another). Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention with the supply as disclose by Canales et al. in order to supply driving power to each of the plurality of converters, because it enhances the efficiency of such a power station and to optimize control of the converters of such a power station. 9. Claims 10-11 are rejected under 35 U.S.C. 103 as being unpatentable over Zushi et al. (US 20220001750) in view of Siri (US 20140319918) and Canales et al. (US 20170126010). Regarding claim 10: Zushi et al. disclose (i.e. figure 5) a power conversion device comprising: a plurality of converters (i.e. 21 and 22) respectively connected to a plurality of cell strings (i.e. Solar cell module); an auxiliary power supply unit (i.e. 12) configured to supply driving power to each of the plurality of converters (i.e. 21 and 22); and wherein the plurality of converters (i.e. 21 and 22) constitutes a multi-level structure (i.e. series configuration of converters 21, 22), but does not specifically disclose a control unit configured to monitor at least one of an input signal, an output signal of the plurality of converters, and a current flowing in the inductor comprised in each of the converters, wherein the auxiliary power supply unit comprises: a first voltage conversion part configured to convert a first voltage of at least one output terminal from among output terminals of the plurality of cell strings into a second voltage, and output same; and a second voltage conversion part configured to convert the second voltage, outputted from the first voltage conversion part, into a third voltage and supply driving power to each of the plurality of converters and wherein the first voltage conversion part supplies driving power to the control unit. Canales et al. disclose the auxiliary power supply unit (i.e. figure 1) comprises: a first voltage conversion part (i.e. 24, 26) configured to convert a first voltage (i.e. from 12) of at least one output terminal from among output terminals of the plurality of cell strings (i.e. 12, ¶ 21-22) into a second voltage (i.e. from 26), and output same (i.e. same from 12, 26); and a second voltage conversion part (i.e. 28) configured to convert the second voltage (i.e. from 26), outputted from the first voltage conversion part (i.e. 24, 26), into a third voltage (i.e. from 28) and supply driving power to each of the plurality of converters (i.e. 22) (i.e. in addition, the converter 22 are connected in series. Therefore, the converter 18 may supply driving power to each converter via one another); and the inductor (i.e. figure 3: 34) comprised in each of the converter. Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention with the supply as disclose by Canales et al. in order to supply driving power to each of the plurality of converters, because it enhances the efficiency of such a power station and to optimize control of the converters of such a power station. Siri discloses a power supply (i.e. figure 6) comprising a control unit (i.e. 602) configured to monitor at least one of an input signal (i.e. Vin), an output signal (i.e. signal of Vbus) of the plurality of converters (i.e. C04A-C), and a current flowing (i.e. Ibus) in the inductor (i.e. inductor of 604A-C) comprised in each of the converters (i.e. 604a-C), and wherein the converter (i.e. 604A) supplies driving power (i.e. Vbus) to the control unit (i.e. 602), Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention with power supply as disclose by Siri in order to have the first voltage conversion part supplies driving power to the control unit, because it improves power system control architecture. Regarding claim 11: Zushi et al. disclose (i.e. figure 5) the power converter (i.e. 12) operates by receiving an enable signal (i.e. from 43), but does not specifically disclose the control unit outputs an enable signal to the second voltage conversion part, and wherein the second voltage conversion part operates by receiving the enable signal. Canales et al. disclose supply unit (i.e. figure 1) comprises the second voltage conversion part (i.e. 28). Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention with the supply as disclose by Canales et al. to have the control unit outputs an enable signal to the second voltage conversion part, and wherein the second voltage conversion part operates by receiving the enable signal, because it enhances the efficiency of such a power station and to optimize control of the converters of such a power station. 10. Claims 7 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Zushi et al. (US 20220001750) in view of Canales et al. (US 20170126010) and further in view of Maitra et al. (US 20110273917). Regarding claims 7 and 18: Zushi et al. disclose the limitation of the claim(s) as discussed above, but does not specifically disclose the second voltage conversion part supplies power to a device operating at the third voltage. Maitra et al. disclose a power supply comprising the second voltage conversion part (i.e. 34) supplies power to a device (i.e. load connect to 34) operating at the third voltage (i.e. from 34). Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention with the power supply as disclose by Maitra et al., because there is a need for a photovoltaic interface that would simultaneously upgrade grid capabilities and significantly increase the value of photovoltaic modules while reducing the actual cost of labor and equipment. 11. Claims 9 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Zushi et al. (US 20220001750) in view of Canales et al. (US 20170126010) and further in view of Takai et al. (US 20150194256). Regarding claims 9 and 20: Zushi and Canales et al. et al. disclose the limitation of the claim(s) as discussed above, but does not specifically disclose the second voltage conversion part comprises an insulation type converter. Takai et al. disclose a power conversion (i.e. figure 1) comprising voltage conversion part comprises an insulation type converter (i.e. ¶ 34). Therefore, it would have been obvious to one with ordinary skill in the art before the earliest effective filing date to modify the circuit of Zushi et al.’s invention to have the second voltage conversion part comprises an insulation type converter, with the power conversion as disclose by Takai et al., because desired power can be exchanged between the ports on basis of the same principle and to suppress the Joule loss in the magnetic coupling inductor. Conclusion 12. Any inquiry concerning this communication or earlier communications from the examiner should be directed to NGUYEN TRAN whose telephone number is (571)270-1269. The examiner can normally be reached Flex: M-F 8-7. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Monica Lewis can be reached at 571-272-1838. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /Nguyen Tran/ Primary Examiner, Art Unit 2838
Read full office action

Prosecution Timeline

Dec 27, 2023
Application Filed
Jan 08, 2026
Non-Final Rejection — §103, §112 (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
83%
Grant Probability
91%
With Interview (+7.6%)
2y 6m
Median Time to Grant
Low
PTA Risk
Based on 1073 resolved cases by this examiner. Grant probability derived from career allow rate.

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