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 .
Information Disclosure Statement
The information disclosure statement submitted on 30 Jul 2025 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Drawings
The drawings are objected to as failing to comply with 37 CFR 1.84(p)(5) because they include the following reference character(s) not mentioned in the description: 107A and 107B. Corrected drawing sheets in compliance with 37 CFR 1.121(d), or amendment to the specification to add the reference character(s) in the description in compliance with 37 CFR 1.121(b) 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. 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.
The drawings are objected to because:
Fig 1: this drawing is missing a boundary around the power conversion circuit 105. It is unclear which components are included in 105.
Fig 1: this drawing is missing a boundary around inductor 160, to include 161, 162, and 163. It is unclear which components are included in 160.
Specification
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:
The specification [0023] states, "when two components are said to be "coupled" or "operably coupled," this includes components that are associated in any way such that power or signal information may be transferred (directly or indirectly) from one to another, and thus these terms do not require a direct connection between the components with no intermediaries." The specification [0037] then states, "Any AC voltage present across the input inductor is electro-magnetically coupled to the auxiliary winding." Contradictorily to those statements, claim 1 and 10 recite the limitation “an auxiliary winding wound around the core element and not coupled to the input terminal”.
The disclosure is objected to because of the following informalities:
All instances referring to the inductor as “106” should be changed to inductor “160”, as shown in Fig 2A.
[0031]: “power conversion circuit 150” should be changed to “power conversion circuit 105”, as shown in Fig1.
The term “adjusted desired output voltage level” requires a reference character. Due to inconsistencies in the specification [0027-34], it is unclear whether the second signal is referring to “adjusted desired output voltage level” or not.
The term “desired output voltage level” requires a reference character. Due to inconsistencies in the specification [0027-34], it is unclear whether the second signal is referring to “desired output voltage level” or not.
Appropriate correction is required.
Claim Objections
Claims 5-8 and 14-17 are objected to because of the following informalities:
Claim 5, lines 2-3: recites the limitation, “the output voltage of the DC-to-DC converter”. There is insufficient antecedent basis for this limitation in the claim.
Claim 14 suffers from the same defect as Claim 5.
Claim 6, line 2: recites the limitation, “the flow of current”. There is insufficient antecedent basis for this limitation in the claim.
Claim 6, line 5: recites the limitation, “the operation of the power conversion circuit”. There is insufficient antecedent basis for this limitation in the claim.
Claim 6, line 6: recites the limitation, “the primary winding”. There is insufficient antecedent basis for this limitation in the claim.
Claim 6, line 9: recites the limitation, “the output voltage of the power conversion circuit”. There is insufficient antecedent basis for this limitation in the claim.
Claim 15 suffers from the same defects as Claim 6.
Claims 7-8 depend from Claim 6 and thus have at least the same defects.
Claims 16-17 depend from Claim 15 and thus have at least the same defects.
Claim 8, line 1: the limitation “any of” should be removed.
Claim 17 suffers from the same defect as Claim 8.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
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.
Claims 1-18 are 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 and 10: recite the limitation, “an auxiliary winding wound around the core element and not coupled to the input terminal”. However the specification [0037] states: "Any AC voltage present across the input inductor is electro-magnetically coupled to the auxiliary winding." And additionally, [0023] states: "when two components are said to be "coupled" or "operably coupled," this includes components that are associated in any way such that power or signal information may be transferred (directly or indirectly) from one to another, and thus these terms do not require a direct connection between the components with no intermediaries." Correspondence between the specification and claims is required, see MPEP § 2173.02. For purposes of examination, Examiner assumes this means the auxiliary winding is galvanically isolated from the input terminal, which is supported in [0037].
Claims 2-9 depend from Claim 1 and thus have at least the same defect(s).
Claims 11-18 depend from Claim 10 and thus have at least the same defect(s).
Claims 1 and 10: the limitations, “desired output voltage level” and “adjusted desired output voltage level” are indefinite. [0029] states: "The voltage control circuit 150 is further configured to adjust the desired output voltage level based on the first signal 163S. " [0027] instead states: "The converter 10 also includes an output terminal 107 coupled to a power conversion circuit 105 and configured to provide an adjusted desired output voltage level." Correspondence between the specification and claims is required, see MPEP § 2173.02. For purposes of examination, Examiner assumes the voltage control circuit gets “desired output voltage level” from the power conversion circuit as one of its inputs. The voltage control circuit adjusts the “desired output voltage level” to ultimately produce the “adjusted desired output voltage level”.
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 1-5, 7, 9-14, 16, and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Weichel ("Active Stabilization of a DC-DC Step-Down Converter with Input LC Filter Via Current-Mode Control and Input Voltage Feedback") in view of Xiao (US 20170324333 A1).
Regarding Claim 1, Weichel discloses a DC-to-DC converter (see Fig 2.1/2.2) comprising: an input terminal configured to receive a direct current (DC) input voltage (v.sub.i coupled to the input at L.sub.i, Fig 2.1/2.2, p11); an input filter coupled to the input terminal, the input filter comprising an inductor (LC filter includes L.sub.i, Fig 2.1/2.2, p11), a power conversion circuit coupled to the input filter and configured to convert the DC input voltage to a desired output voltage level (D, 1-D, Lo, Co, Ro, are in the power conversion circuit and it is connected to the input filter Li/Ci and converts V.sub.i into output voltage v.sub.Co, Eq 3.2, Fig 2.1, p11/22) and comprising a voltage control circuit, the voltage control circuit configured to: receive a first signal from the auxiliary winding of the inductor of the input filter, the first signal being indicative of an output voltage of the input filter (ṽ.sub.Ci "is the ripple component of the input capacitor voltage" at the output of the input filter, Eq 3.2, Fig 4.1/4.3, p22); and adjust the desired output voltage level based on the first signal (Eq 3.2 shows that v.sub.control uses the output voltage of the input filter, ṽ.sub.Ci, and desired output voltage, v.sub.Co; v.sub.control is fed into the current mode controller of Fig 4.1/4.3 to drive the switches to v.sub.Co, p22/36); and an output terminal coupled to the power conversion circuit and configured to provide the adjusted desired output voltage level (v.sub.Co is measured at the output of the buck converter, Fig 2.1, p11).
Weichel does not disclose a core element; at least one primary winding wound around the core element and coupled to the input terminal; and an auxiliary winding wound around the core element and not coupled to the input terminal.
Xiao teaches a conventional filter inductor for use in a power converter (see Fig 2) including a core element (204, Fig 2); at least one primary winding wound around the core element and coupled to the input terminal (LP, Fig 2); and an auxiliary winding wound around the core element and not coupled to the input terminal ("The secondary winding LS is magnetically coupled with the filter inductor LP to conduct a second current I2 induced by flow of the first current I1 through the filter inductor LP.", LP, Fig 2, [0017]).
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 inductor in Weichel, as taught by Xiao, as it provides the advantage of protecting low voltage controller electronics from high input voltage of the filter.
Regarding Claim 2, the combination of Weichel and Xiao discloses all of the limitations of Claim 1, and further discloses wherein the inductor is a differential mode inductor ("The filter inductor LP is connected between a filter input line 201 and a rectifier side filter output line 202, and conducts a first current I1 between the AC input … and the rectifier", Fig 2, [0017] of Xiao).
Regarding Claim 3, the combination of Weichel and Xiao discloses all of the limitations of Claim 1, and further discloses wherein the first signal is indicative of an AC component of the output voltage of the input filter (ṽ.sub.Ci "is the ripple component of the input capacitor voltage" at the output of the input filter, Eq 3.2, Fig 4.1/4.3, p22 of Weichel).
Regarding Claim 4, the combination of Weichel and Xiao discloses all of the limitations of Claim 1, and further discloses wherein the at least one primary winding comprises a single primary winding, or two primary windings coupled in series ("The filter inductor LP is connected between a filter input line 201 and a rectifier side filter output line 202" is a single primary winding, Fig 2, [0017] of Xiao).
Regarding Claim 5, the combination of Weichel and Xiao discloses all of the limitations of Claim 1, and further discloses wherein the voltage control circuit is further configured to receive signals from the output terminal indicative of the output voltage of the DC-to-DC converter (Eq 3.2 shows that v.sub.control uses the desired output voltage v.sub.Co, p22/36 of Weichel).
Regarding Claim 9, the combination of Weichel and Xiao discloses all of the limitations of Claim 1, and further discloses further comprising an output filter coupled to the output terminal, the output filter comprising a capacitor (capacitor Co is part of the output LC filter, along with Lo, Fig 2.1, p11 of Weichel).
Regarding claim 10, Weichel discloses a method of providing DC-to-DC power conversion (see Fig 2.1/2.2), the method comprising: receiving a direct current (DC) input voltage at an input terminal of a DC-to-DC converter (v.sub.i coupled to the input at L.sub.i, Fig 2.1/2.2, p11), the DC-to-DC converter comprising: the input terminal ( top terminal of v.sub.i, Fig 2.1/2.2, p11); an input filter coupled to the input terminal, the input filter comprising an inductor (v.sub.i coupled to the input contains L.sub.i, Fig 2.1/2.2, p11); a power conversion circuit coupled to the input filter and comprising a voltage control circuit (D, 1-D, Lo, Co, Ro, and the controller for the switches are connected to the input filter Li/Ci, Eq 3.2, Fig 2.1, p11/22); and an output terminal coupled to the power conversion circuit (v.sub.Co is measured at the node between Lo, Co, and Ro, Fig 2.1, p11); the power conversion circuit converting the DC input voltage to a desired output voltage level (D, 1-D, Lo, Co, Ro, and the controller for the switches are in the power conversion circuit that converts V.sub.i into output voltage v.sub.Co, Eq 3.2, Fig 2.1/4.1/4.3, p11/22/36/40); the voltage control circuit receiving a first signal from the auxiliary winding of the inductor of the input filter, the first signal being indicative of an output voltage of the input filter (ṽ.sub.Ci "is the ripple component of the input capacitor voltage" at the output of the input filter, Eq 3.2, Fig 4.1/4.3, p22); the voltage control circuit causing an adjustment to the desired output voltage level based on the first signal; and the output terminal providing the adjusted desired output voltage level (Eq 3.2 shows that v.sub.control uses the output voltage of the input filter, ṽ.sub.Ci, and desired output voltage, v.sub.Co; v.sub.control is fed into the current mode controller of Fig 4.1/4.3 to drive the switches to v.sub.Co, p22/36).
Weichel does not disclose a core element; at least one primary winding wound around the core element and coupled to the input terminal; and an auxiliary winding wound around the core element and not coupled to the input terminal.
Xiao teaches a conventional filter inductor for use in a power converter (see Fig 2) including a core element (204, Fig 2); at least one primary winding wound around the core element and coupled to the input terminal (LP, Fig 2); and an auxiliary winding wound around the core element and not coupled to the input terminal ("The secondary winding LS is magnetically coupled with the filter inductor LP to conduct a second current I2 induced by flow of the first current I1 through the filter inductor LP.", LP, Fig 2, [0017]).
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 inductor in Weichel, as taught by Xiao, as it provides the advantage of protecting low voltage controller electronics from high input voltage of the filter.
Regarding claim 11, it is rejected for the same reasons as stated above for Claim 2.
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 18, it is rejected for the same reasons as stated above for Claim 9.
Claims 6-8 and 15-17 are rejected under 35 U.S.C. 103 as being unpatentable over Weichel ("Active Stabilization of a DC-DC Step-Down Converter with Input LC Filter Via Current-Mode Control and Input Voltage Feedback") in view of Xiao (US 20170324333 A1), and further in view of Nishiyama (US 20100103703 A1).
Regarding Claim 6, the combination of Weichel and Xiao discloses all of the limitations of Claim 1, and further discloses wherein the power conversion circuit further comprises: a switching circuit and a switch controller configured to regulate the flow of current through the power conversion circuit (current mode controller drives the switches to regulate the current, Fig 4.1, p36 of Weichel); an energy storage element coupled to the switching circuit and configured to store and release energy during the operation of the power conversion circuit (Ci, Fig 2.1, p11 of Weichel); wherein a switching operation of the switching circuit is based on a second signal from the voltage control circuit (v.sub.control is fed into the current mode controller of Fig 4.1 to drive the switches, p22/36 of Weichel).
The combination of Weichel and Xiao does not disclose a transformer having a primary winding and a secondary winding, the primary winding coupled to the switching circuit; and a rectifier coupled to the secondary winding of the transformer and configured to rectify the output voltage of the power conversion circuit to provide the desired output voltage level.
Nishiyama teaches a conventional isolated DC-DC converter (see Fig 1) including a transformer having a primary winding and a secondary winding, the primary winding coupled to the switching circuit (T10's primary winding is coupled to 211, Fig 1); and a rectifier coupled to the secondary winding of the transformer and configured to rectify the output voltage of the power conversion circuit to provide the desired output voltage level (T10's secondary winding is coupled to 208 at the output, Fig 1); wherein a switching operation of the switching circuit is based on a second signal from the voltage control circuit (, 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 isolated DC-DC converter in Weichel, as taught by Nishiyama, as it provides the advantage of galvanic isolation between the primary side switching element and the regulated output while still allowing the switch to be controlled from the primary side ([0019] of Nishiyama).
Regarding Claim 7, the combination of Weichel, Xiao, and Nishiyama discloses all of the limitations of Claim 6, and further discloses wherein the energy storage element is a capacitor, and wherein the capacitor also forms part of the input filter (Ci is part of the input LC filter, Fig 2.1, p11 of Weichel).
Regarding Claim 8, the combination of Weichel, Xiao, and Nishiyama discloses all of the limitations of Claim 6, and further discloses wherein the power conversion circuit further comprises an optocoupler or an opto-emulator coupled to the voltage control circuit and the switch controller (photocoupler 702a/b, Fig 1 of Nishiyama).
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 17, it is rejected for the same reasons as stated above for Claim 8.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Mirafzal (US 20080080106 A1) discloses a power conversion system including an integrated DC link inductor and current sensor winding with a core that has at least two primary windings and a secondary winding.
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.
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, Crystal Hammond can be reached at (571) 270-1682. 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.
/J.C.C./Examiner, Art Unit 2838
/GARY L LAXTON/Primary Examiner, Art Unit 2838 9/28/2026
Prosecution Insights