DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after allowance or after an Office action under Ex Parte Quayle, 25 USPQ 74, 453 O.G. 213 (Comm'r Pat. 1935). Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, prosecution in this application has been reopened pursuant to 37 CFR 1.114. Applicant's submission filed on 24 Jun 2026 has been entered.
Information Disclosure Statement
The information disclosure statements submitted on 24 Jun 2026 and 28 May 2026 are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements are being considered by the examiner.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claims 1, 9-10, & 18 are rejected under 35 U.S.C. 103 as being unpatentable over Huang (US 12095369 B2) in view of Agrawal ("Variable-Frequency Critical Soft-Switching of Wide-Bandgap Devices for Efficient High-Frequency Nonisolated DC-DC Converters").
Regarding Claim 1, Huang discloses a non-isolated power converter system (see Fig 1), the system comprising: a power converter (130, Fig 1) including power switching elements (M1-2, Fig 1); a controller configured to drive the power switching elements to convert received power and to output converted power (140 drives M1-2 to convert input to output power, Fig 1), the controller configured to drive the power switching elements (140 drives M1-2, Fig 1), and a filter including an inductor (inductor 120 and "Capacitors, such as input capacitors, supply capacitors, and other components not necessary to the understanding of the invention are not shown in FIG. 1 for clarity of illustration.", Fig 1, Col 2[27-30]), the filter coupled to a first side of the power converter to filter a power signal on the first side of the power converter (120 is on the right side of the converter, Fig 1), wherein the inductor includes a core portion and a winding portion ("The output inductor 120 comprises a conductor 301 and a magnetic core 302 that surrounds the conductor 301.", Fig 3, Col 4 [37-9]), wherein the winding portion includes a winding embedded in a printed circuit board ("The output inductors 120-1 and 120-2, which are represented by dotted lines in FIG. 2, are embedded within the substrate 200.", "substrate 200, which in one embodiment is a printed circuit board (PCB).", Fig 3, Col 3 [24-5, 58-60]), and and wherein the printed circuit board further includes, located thereon, one or more of: the controller, or one or more of the power switching elements (413B contains a PCB with embedded controller and switches, Fig 4, Col 13 [4-18]).
Huang does not disclose using variable frequency soft switching, a capacitor, the power signal received by the filter having a current ripple of at least 200% peak-to-peak ripple with respect to local average current.
Agrawal ("Variable-Frequency Critical Soft-Switching of Wide-Bandgap Devices for Efficient High-Frequency Nonisolated DC-DC Converters") Agrawal teaches a conventional output filter capacitor and control scheme for use in a power converter (Fig 1) including the controller configured to drive the power switching elements using variable frequency soft switching ("variable frequency critical soft switching control method", abstract); and a filter (L & the capacitor connected in parallel with Vout, Fig 1) including an inductor (L, Fig 1) and a capacitor (the capacitor connected in parallel with Vout, Fig 1), the filter coupled to a first side of the power converter to filter a power signal on the first side of the power converter (right side of the converter, Fig 1), the power signal received by the filter having a current ripple of at least 200% peak-to-peak ripple with respect to local average current (the ripple current is 220-300% of the average current through the inductor L in Fig 1, pg 6090, paragraph 5).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the output filter capacitor and control scheme in Huang, as taught by Agrawal, as it provides the advantage of enabling zero voltage switching with reduced switching losses (abstract of Agrawal).
Regarding Claim 9, the combination of Huang and Agrawal teaches all of the limitations of claim 1, and further teaches wherein the first side of the power converter (right side of converter of Agrawal, Fig 1) is one selected from the group of an DC output side (right side DC output is Vout, Fig 1 of Agrawal) for DC/DC converting, an AC output side for DC/AC inverting, and an AC input side for AC/DC rectifying (DC/DC converter, abstract of Agrawal).
Regarding Claim 10, it is rejected for the same reasons as stated above for claim 1.
Regarding Claim 18, it is rejected for the same reasons as stated above for claim 9.
Claims 2 & 11 are rejected under 35 U.S.C. 103 as being unpatentable over Huang (US 12095369 B2) in view of Agrawal ("Variable-Frequency Critical Soft-Switching of Wide-Bandgap Devices for Efficient High-Frequency Nonisolated DC-DC Converters"), and further in view of Schaefer ("Optimal Design of Highly Efficient and Highly Compact PCB Winding Inductors").
Regarding Claim 2, the combination of Huang and Agrawal discloses all of the limitations of claim 1.
The combination of Huang and Agrawal does not disclose wherein each loop of the winding is a wire conductor with a solid cross-section.
Schaefer teaches a conventional inductor wherein each loop of the winding is a wire conductor with a solid cross-section ("solid conductor windings", p3 paragraph 2).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the inductor in Huang, as taught by Schaefer, as it provides the advantage of reducing resistive power loss.
Regarding Claim 11, it is rejected for the same reasons as stated above for claim 2.
Claims 3-7, 12-16, 44-48, 53-57, & 60 are rejected under 35 U.S.C. 103 as being unpatentable over Huang (US 12095369 B2) in view of Agrawal ("Variable-Frequency Critical Soft-Switching of Wide-Bandgap Devices for Efficient High-Frequency Nonisolated DC-DC Converters"), and further in view of Zhou ("Inductor Design for Nonisolated Critical Soft Switching Converters Using Solid and Litz PCB and Wire Windings Leveraging Neural Network Model").
Regarding Claim 3, the combination of Huang and Agrawal teaches all of the limitations of claim 1.
The combination of Huang and Agrawal does not teach wherein the winding embedded in the printed circuit board forms a litz PCB in which the winding includes multiple layers of parallel strands routed in the printed circuit board.
Zhou teaches a conventional multi-layer litz PCB winding structure for use in a power converter (Fig 1) including wherein the winding embedded in the printed circuit board forms a litz PCB in which the winding includes multiple layers of parallel strands routed in the printed circuit board ("This article develops a 3-D litz PCB routing method to combine the advantages of both litz wire and PCB winding. The method is designed by applying the litz structure of round twisted wire to PCB routing for multiple layers.", pg 3362, paragraph 2).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the multi-layer litz PCB winding structure in Huang, as taught by Zhou, as it provides the advantage of reducing high-frequency copper losses (abstract of Zhou).
Regarding Claim 4, the combination of Huang, Agrawal, and Zhou teaches all of the limitations of claim 3, and further teaches wherein the litz PCB includes at least two layers of parallel strands, and each strand of the parallel strands is a conductive trace ("The litz type of conductor could be adopted for reducing the ac losses by winding multiple strands of conductors in parallel" and Fig 8-9 show a four-layer litz PCB, Fig 8-9, p3358 line 14-16 of Zhou).
Regarding Claim 5, the combination of Huang, Agrawal, and Zhou teaches all of the limitations of claim 3, and further teaches wherein the winding portion includes one or more additional litz PCBs, each additional litz PCB including an additional winding including multiple layers of parallel strands routed in the additional litz PCB ("These castellated holes help to mount one PCB winding board on top of another" and Fig 8-9 show a four-layer 40-strand litz PCB, Fig 8-9, pg 3364, last sentence of Zhou).
Regarding Claim 6, the combination of Huang and Agrawal teaches all of the limitations of claim 1.
The combination of Huang and Agrawal does not teach wherein the core portion includes a first core portion on an opposite side of the winding portion as a second core portion, wherein the first core portion and the second core portion include planar surfaces facing a conductor loop formed by the winding and parallel to the printed circuit board.
Zhou teaches a conventional multi-layer litz PCB winding structure for use in a power converter (Fig 1) including wherein the core portion includes a first core portion on an opposite side of the winding portion as a second core portion, wherein the first core portion and the second core portion include planar surfaces facing a conductor loop formed by the winding and parallel to the printed circuit board (Fig 10c shows top and bottom planar core portions opposite each other and both facing the winding portion, Fig 10c of Zhou).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the multi-layer litz PCB winding structure in Huang, as taught by Zhou, as it provides the advantage of reducing high-frequency copper losses (abstract of Zhou).
Regarding Claim 7, the combination of Huang and Agrawal teaches all of the limitations of claim 1.
The combination of Huang and Agrawal does not teach non-isolated power converter system of claim 1, wherein the core portion includes a first core portion opposite an open air portion, the first core portion having a base portion and three legs extending therefrom, wherein a middle leg of the three legs extends through the opening defined by a conductor loop.
Zhou teaches a conventional multi-layer litz PCB winding structure for use in a power converter (Fig 1) including a non-isolated power converter system of claim 1, wherein the core portion includes a first core portion opposite an open air portion, the first core portion having a base portion and three legs extending therefrom, wherein a middle leg of the three legs extends through the opening defined by a conductor loop (Fig 10d shows a 3-legged core portion that is open at the top with a conductor loop around the middle leg, Fig 10d of Zhou).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the multi-layer litz PCB winding structure in Huang, as taught by Zhou, as it provides the advantage of reducing high-frequency copper losses (abstract of Zhou).
Regarding Claim 12, it is rejected for the same reasons as stated above for claim 3.
Regarding Claim 13, it is rejected for the same reasons as stated above for claim 4.
Regarding Claim 14, it is rejected for the same reasons as stated above for claim 5.
Regarding Claim 15, it is rejected for the same reasons as stated above for claim 6.
Regarding Claim 16, it is rejected for the same reasons as stated above for claim 7.
Regarding Claim 44, Huang discloses a non-isolated power converter system (see Fig 1), the system comprising: a power converter (130, Fig 1) including power switching elements (M1-2, Fig 1); a controller configured to drive the power switching elements to convert received power and to output converted power (140 drives M1-2 to convert input to output power, Fig 1); a filter including an inductor (inductor 120 and "Capacitors, such as input capacitors, supply capacitors, and other components not necessary to the understanding of the invention are not shown in FIG. 1 for clarity of illustration.", Fig 1, Col 2[27-30]), the filter coupled to a first side of the power converter to filter a power signal on the first side of the power converter (120 is on the right side of the converter, Fig 1), wherein the inductor includes a core portion and a winding portion ("The output inductor 120 comprises a conductor 301 and a magnetic core 302 that surrounds the conductor 301.", Fig 3, Col 4 [37-9]); and a printed circuit board ("substrate 200, which in one embodiment is a printed circuit board (PCB).", Fig 3, Col 3 [24-5, 58-60]), the printed circuit board having embedded thereon a winding of the winding portion ("The output inductors 120-1 and 120-2, which are represented by dotted lines in FIG. 2, are embedded within the substrate 200.", "substrate 200, which in one embodiment is a printed circuit board (PCB).", Fig 3, Col 3 [24-5, 58-60]); and the printed circuit board having located thereon one or more of: the controller, or one or more of the power switching elements ("The top view of the substrate 200 shows the “component side” of the substrate 200…The switch blocks 110, capacitors, and other components are mounted on the component side.", Fig 2, Col 3 [25-9]).
Huang does not disclose an output filter with a capacitor, wherein the winding embedded in the printed circuit board forms a litz PCB in which the winding includes multiple layers of parallel strands routed in the printed circuit board.
Agrawal teaches a conventional output filter capacitor for use in a power converter (Fig 1) including a filter including an inductor and a capacitor (L & the capacitor connected in parallel with Vout, Fig 1).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the filter in Huang, as taught by Agrawal, as it provides the advantage of completing a conventional LC filter for smoothing the voltage/current at the output.
Agrawal does not disclose wherein the winding embedded in the printed circuit board forms a litz PCB in which the winding includes multiple layers of parallel strands routed in the printed circuit board.
Zhou teaches a conventional multi-layer litz PCB winding structure (Fig 5) including wherein the winding embedded in the printed circuit board forms a litz PCB in which the winding includes multiple layers of parallel strands routed in the printed circuit board ("This article develops a 3-D litz PCB routing method to combine the advantages of both litz wire and PCB winding. The method is designed by applying the litz structure of round twisted wire to PCB routing for multiple layers.", pg 3362, paragraph 2).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the multi-layer litz PCB winding structure in Huang, as taught by Zhou, as it provides the advantage of reducing high-frequency copper losses (abstract of Zhou).
Regarding Claim 45, it is rejected for the same reasons as stated above for Claim 4.
Regarding Claim 46, it is rejected for the same reasons as stated above for Claim 5.
Regarding Claim 47, it is rejected for the same reasons as stated above for Claim 6.
Regarding Claim 48, it is rejected for the same reasons as stated above for Claim 7.
Regarding Claim 53, Huang discloses a method of power conversion, the method comprising: receiving, by a power converter including power switching elements input power (130 receives input power and includes switches M1-2, Fig 1); driving, by a controller, the power switching elements to convert received input power to output converted power (140 drives M1-2 to convert input to output power, Fig 1), one or more of (i) the controller, or (ii) one or more of the power switching elements being located on a printed circuit board (413B contains a PCB with embedded controller and switches, Fig 4, Col 13 [4-18]); and filtering, by an LC filter including an inductor (inductor 120 and "Capacitors, such as input capacitors, supply capacitors, and other components not necessary to the understanding of the invention are not shown in FIG. 1 for clarity of illustration.", Fig 1, Col 2[27-30]), wherein the inductor includes a core portion and a winding portion ("The output inductor 120 comprises a conductor 301 and a magnetic core 302 that surrounds the conductor 301.", Fig 3, Col 4 [37-9]), wherein the winding portion includes a winding embedded in the printed circuit board ("The output inductors 120-1 and 120-2, which are represented by dotted lines in FIG. 2, are embedded within the substrate 200.", "substrate 200, which in one embodiment is a printed circuit board (PCB).", Fig 3, Col 3 [24-5, 58-60]).
Huang does not disclose a capacitor that is coupled to a first side of the power converter, a power signal on the first side of the power converter, wherein the winding embedded in the printed circuit board forms a litz PCB in which the winding includes multiple layers of parallel strands routed in the printed circuit board.
Agrawal teaches a conventional output filter capacitor for use in a power converter (Fig 1) including filtering, by an LC filter including an inductor and a capacitor that is coupled to a first side of the power converter, a power signal on the first side of the power converter (L & the capacitor connected in parallel with Vout filter power on the right side of the converter, Fig 1).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the filter in Huang, as taught by Agrawal, as it provides the advantage of completing a conventional LC filter for smoothing the voltage/current at the output.
Agrawal does not teach wherein the winding embedded in the printed circuit board forms a litz PCB in which the winding includes multiple layers of parallel strands routed in the printed circuit board.
Zhou teaches wherein the winding embedded in the printed circuit board forms a litz PCB in which the winding includes multiple layers of parallel strands routed in the printed circuit board ("This article develops a 3-D litz PCB routing method to combine the advantages of both litz wire and PCB winding. The method is designed by applying the litz structure of round twisted wire to PCB routing for multiple layers.", pg 3362, paragraph 2).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the multi-layer litz PCB winding structure in Huang, as taught by Zhou, as it provides the advantage of reducing high-frequency copper losses (abstract of Zhou).
Regarding Claim 54, it is rejected for the same reasons as stated above for Claim 4.
Regarding Claim 55, it is rejected for the same reasons as stated above for Claim 5.
Regarding Claim 56, it is rejected for the same reasons as stated above for Claim 6.
Regarding Claim 57, it is rejected for the same reasons as stated above for Claim 7.
Regarding Claim 60, Huang discloses a non-isolated power converter system (see Fig 1), the system comprising: a power converter (130, Fig 1) including power switching elements (M1-2, Fig 1); a controller configured to drive the power switching elements to convert received power and to output converted power (140 drives M1-2 to convert input to output power, Fig 1), the controller configured to drive the power switching elements (140 drives M1-2, Fig 1), and a filter including an inductor (inductor 120 and "Capacitors, such as input capacitors, supply capacitors, and other components not necessary to the understanding of the invention are not shown in FIG. 1 for clarity of illustration.", Fig 1, Col 2[27-30]), the filter coupled to a first side of the power converter to filter a power signal on the first side of the power converter (120 is on the right side of the converter, Fig 1), wherein the inductor includes a core portion and a winding portion ("The output inductor 120 comprises a conductor 301 and a magnetic core 302 that surrounds the conductor 301.", Fig 3, Col 4 [37-9]), wherein the winding portion includes a winding embedded in a printed circuit board ("The output inductors 120-1 and 120-2, which are represented by dotted lines in FIG. 2, are embedded within the substrate 200.", "substrate 200, which in one embodiment is a printed circuit board (PCB).", Fig 3, Col 3 [24-5, 58-60]).
Huang does not disclose using variable frequency soft switching, a filter with a capacitor on the first side of the power converter, the power signal received by the filter having a current ripple of at least 200% peak-to-peak ripple with respect to local average current, and wherein the core portion includes a first core portion opposite an open air portion, the first core portion having a base portion and three legs extending therefrom, wherein a middle leg of the three legs extends through the opening defined by a conductor loop.
Agrawal teaches a conventional output filter capacitor and control scheme for use in a power converter (Fig 1) including the controller configured to drive the power switching elements using variable frequency soft switching ("variable frequency critical soft switching control method", abstract); and a filter (L & the capacitor connected in parallel with Vout, Fig 1) including an inductor (L, Fig 1) and a capacitor (the capacitor connected in parallel with Vout, Fig 1), the filter coupled to a first side of the power converter to filter a power signal on the first side of the power converter (right side of the converter, Fig 1), the power signal received by the filter having a current ripple of at least 200% peak-to-peak ripple with respect to local average current (the ripple current is 220-300% of the average current through the inductor L in Fig 1, pg 6090, paragraph 5).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the control scheme in Huang, as taught by Agrawal, as it provides the advantage of enabling zero voltage switching with reduced switching losses (abstract of Agrawal).
Agrawal does not teach wherein the core portion includes a first core portion opposite an open air portion, the first core portion having a base portion and three legs extending therefrom, wherein a middle leg of the three legs extends through the opening defined by a conductor loop.
Zhou teaches a conventional EA core (Fig 5) including wherein the core portion includes a first core portion opposite an open air portion, the first core portion having a base portion and three legs extending therefrom, wherein a middle leg of the three legs extends through the opening defined by a conductor loop (Fig 10d shows a 3-legged core portion that is open at the top with a conductor loop around the middle leg, Fig 10d of Zhou).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the EA core in Huang, as taught by Zhou, as it provides the advantage of reducing magnetic core material and manufacturing cost (p3371 lines 13-14 of Zhou).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JENNIFER C CAULK whose telephone number is (571)270-0623. The examiner can normally be reached M-F 8:30-5:30, every other Fri off.
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/J.C.C./Examiner, Art Unit 2838
/GARY L LAXTON/Primary Examiner, Art Unit 2838 8/04/2026
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