DETAILED ACTION
This Office action is in response to the claim set filed on 30 July 2026.
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 .
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Election/Restrictions
Applicant’s election without traverse of Species XX in the reply filed on 30 July 2026 is acknowledged. Claims 7, 9-14 and 19 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to nonelected species, there being no allowable generic or linking claim.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1 and 15 is/are rejected under 35 U.S.C. 102(a)(1) and 102(a)(2) as being anticipated by Das et al. (US 2020/0212795; hereinafter “Das”).
In re claim 1, Das discloses a conversion circuit (Fig. 9A) for converting a voltage of a power supply (Vin) and powering a load (Io900) by the converted voltage (Vo900), the power supply and the load each comprising a first end and a second end (load shown having ends at Vo900 and ground; power supply Vin is understood to be referenced, that is connected, to the same ground node), and the second end of the power supply being connected to the second end of the load (at ground node), the conversion circuit comprising:
a full-wave rectifier circuit (L901, S909, L902, S908) connected in parallel to the load (between Vo900 and ground) having a first rectifying branch (L901, S909) and a second rectifying branch (L902, S908) connected in parallel (between Vo900 and ground), the first rectifying branch having a first rectifying switch (S909) and a first winding (L901) connected in series (between Vo900 and ground), the first rectifying switch and the first winding being connected to form a first midpoint (Vx901), the second rectifying branch having a second rectifying switch (S908) and a second winding (L902) connected in series (between Vo900 and ground), the second rectifying switch and the second winding being connected to form a second midpoint (Vx902), wherein the first winding and the second winding are coupled to each other (at Vo900);
a first switching circuit (S901-S906, L903) being directly connected between the first end of the power supply (Vin) and the first end of the load (Vo900), and comprising a first switch (S901) and a second switch (S902) connected in series to form a first connection node (node between S901, S902); and
a resonant branch (C901) being directly connected between the first connection node (node between S901, S902) and the first midpoint (Vx901), the resonant branch comprising a first resonant unit (C901).
In re claim 15, Das discloses (Fig. 9A) wherein, the first switching circuit (S901-S906, L903) further comprises a third switch (S903) and a fourth switch (S904) connected in series to the first switch (S901) and the second switch (S902), the second switch (S902) and the third switch (S903) being connected to form a second connection node (node between S902 and S903), and the third switch (S903) and the fourth switch (S904) being connected to form a third connection node (node between S903 and S904), the conversion circuit further comprises:
a first energy storage unit (C902) comprising an energy storage element (C902), and having one end connected to the second connection node (node between S902 and S903), and the other end connected to the second rectifying branch (L902, S908); and
a second resonant unit (C904) electrically coupled between the third connection node (node between S903 and S904) and the first midpoint (Vx901).
Claim(s) 1 is/are rejected under 35 U.S.C. 102(a)(1) and 102(a)(2) as being anticipated by Petersen (US Patent 10,756,623).
In re claim 1, Petersen discloses a conversion circuit (Fig. 11) for converting a voltage of a power supply (Vin) and powering a load (Cout or other load, not shown at output 1104) by the converted voltage (Vout), the power supply and the load each comprising a first end and a second end (as shown), and the second end of the power supply (ground at 201) being connected to the second end of the load (ground at 201), the conversion circuit comprising:
a full-wave rectifier circuit (L1, L2, S4, S8) connected in parallel to the load (between 1104 and ground 201) having a first rectifying branch (L1, S4) and a second rectifying branch (L2, S8) connected in parallel (between 1104 and ground 201), the first rectifying branch having a first rectifying switch (S4) and a first winding (L1) connected in series (as shown), the first rectifying switch and the first winding being connected to form a first midpoint (208), the second rectifying branch having a second rectifying switch (S8) and a second winding (L2) connected in series (as shown), the second rectifying switch and the second winding being connected to form a second midpoint (212), wherein the first winding and the second winding are coupled to each other (e.g., at node 1104);
a first switching circuit (S10, S1, S2) being directly connected between the first end of the power supply and the first end of the load (S10, S1, S2 connected directly between Vin at 202 and load at 1104), and comprising a first switch (S10 or S1) and a second switch (S2) connected in series to form a first connection node (206); and
a resonant branch (C1) being directly connected between the first connection node and the first midpoint (C1 connected directly between node 206 and node 208), the resonant branch comprising a first resonant unit (C1).
Claim(s) 1-6, 8, 15-18 and 20-22 is/are rejected under 35 U.S.C. 102(a)(2) as being clearly anticipated by Ye et al. (US 2022/00141101; hereinafter “Ye”).
With respect to claims 1-6, 8, 15-18 and 20-22, Ye teaches essentially the same circuits that are disclosed in the instant application in Figs. 19, 21C, 21D, 30, 33, 36A, 36B, and 36D. As such, the claimed inventions are considered to be clearly anticipated. Note that this rejection may be overcome if Applicant provides evidence on the record to show that one of the exceptions of 35 U.S.C. 102(b)(2), explained in the paragraph above, is applicable.
Claim Rejections - 35 USC § 103
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.
Claim(s) 2-6, 8 and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Das in view of Wiedenbauer et al. (US 2019/0229613; hereinafter “Wiedenbauer”).
In re claim 2, Das discloses the invention according to claim 1 as explained above, but does not further disclose wherein the resonant branch comprises a third winding connected with the first resonant unit in series, wherein the third winding, the first winding and the second winding are coupled to one another.
Whereas Wiedenbauer discloses a hybrid resonant switched capacitor converter (Fig. 1) in which resonant branches (130 or 132) include a winding (L1 or L2) in series with a resonant capacitor unit (C1 or C2). The addition of the inductive winding provides resonance that enables improved soft-switching of the switches ([0002]).
Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the conversion circuit of Das by incorporating a third winding connected with the first resonant unit in series as shown by Wiedenbauer for the purpose of enabling soft switching of the switches. The result of such modification would include that the first, second, and added third winding would all be coupled to one another, for instance through electrical connection at the mid-points of the rectifying branches and the first end of the load.
In re claim 3, Das discloses the invention according to claim 1 as explained above, but does not further disclose wherein the first resonant unit comprises an inductor and a capacitor connected in series or in parallel. Whereas Wiedenbauer discloses a hybrid resonant switched capacitor converter (Fig. 1) in which resonant branches (130 or 132) include a winding (L1 or L2) in series with a resonant capacitor unit (C1 or C2). The addition of the inductive winding provides resonance that enables improved soft-switching of the switches ([0002]).
Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the conversion circuit of Das by incorporating an inductor connected with the capacitor of the first resonant unit in series as shown by Wiedenbauer for the purpose of enabling soft switching of the switches.
In re claim 42, Das as modified discloses wherein, the first switching circuit (Fig. 9A: S901-S906, L903) further comprises (2m-2[=2]) switches (S903, S904) connected in series to the first switch (S901) and the second switch (S902), such that the first switching circuit comprises 2m[=4] switches (S901-S904) connected in series, wherein adjacent switches of the 2m[=4] switches are connected to form connection nodes (nodes between adjacent switches S901-S904), the conversion circuit further comprises:(m-1)[=1] resonant units (C903), the (m-1) resonant units and the first resonant units (C901) forming m[=2] resonant units (C901, C903), being electrically coupled between the connection node of the (2x-1)th[=1st] switch (S901) and the 2x-th[=2nd] switch (S902) of the 2m[=4] switches (S901-S904) and the first midpoint (e.g., C901 is connected between connection node of 1st and 2nd switches S901, S902 and the first midpoint Vx901); and
(m-1)[=1] energy storage units (C902) each comprising an energy storage element (C902), the k-th[=1st] energy storage unit (C902) of the (m-1)[=1] energy storage units (C902) having one end connected to a connection node of the 2k-th[=2nd] switch (S902) and the (2k+1)th[=3rd] switch (S903) of the 2m[=4] switches (S901-S904), and the other end connected to the second rectifying branch (C902 connected to second rectifying branch at mid-point Vx902), where m, x and k are integers, m≥2, 1≤x≤m and 1≤k≤(m-1).
In re claim 5, Das as modified discloses wherein the x-th[=1st] resonant unit (C901) of the m[=2] resonant units (C901, C903) being connected in series to the third winding (according to the proposed modification, the third winding is placed in series with the resonant unit(s) as explained above).
In re claim 6, Das as modified discloses wherein the energy storage element (C902) is a capacitor (C902).
In re claim 83, Das as modified discloses wherein the other end of each of the (m-1)[=1] energy storage units (C902) is connected to one of: the first end of the load; the second midpoint; and the second end of the load (other end of C902 is connected to second end of load (ground) through switch S908 when it is turned ON).
In re claim 20, Das discloses the invention according to claim 15 as explained above, but does not further disclose wherein the first resonant unit and the second resonant unit have the same resonant frequency. Whereas Wiedenbauer discloses that in order to enable soft-switching, the switching must be performed at the corresponding resonant frequency of the resonant units ([0026]).
Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the conversion circuit of Das by selecting the first and second resonant units to have the same resonant frequency, such that the switching could be performed at the same frequency to enable the soft-switching of all switches as taught by Wiedenbauer.
Claim(s) 21-22 is/are rejected under 35 U.S.C. 103 as being unpatentable over Das.
In re claim 21, Das discloses the invention according to claim 1 as explained above, but does not explicitly disclose in any single embodiment the further addition of a second switching circuit and a third resonant unit, wherein, the second switching circuit is connected in parallel to the first switching circuit, and comprises a fifth switch and a sixth switch connected in series to form a fourth connection node, the third resonant unit electrically coupled between the fourth connection node and the second midpoint.
However, Das teaches that the switched capacitor network making up the input section of the converter may be implemented with various structures to achieve intended operation, characteristics and performance (see [0106]-[0109]). Among the alternative structures also taught in Das is one (See Figs. 26A or 26C) which includes at least one additional switching circuit that is essentially identical to and in parallel with the first switching circuit, across the power supply (i.e., across Vin to ground, as shown in the cited figures), so as to provide full symmetric operation of the circuits and drive the resonant stage(s) with fully symmetric waveforms (see [0012], [0044], [0137]).
Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the converter of Das, Fig. 9A, by essentially duplicating the first switching circuit and first resonant unit as taught by Das, Fig. 26A and in the disclosure, such that there would be included: a second switching circuit and a third resonant unit, wherein, the second switching circuit is connected in parallel to the first switching circuit, and comprises a fifth switch and a sixth switch connected in series to form a fourth connection node, the third resonant unit electrically coupled between the fourth connection node and the second midpoint.
The person of ordinary skill would have been motivated to make the above modification mainly because the suggestion to do so is directly taught by Das, and also because the modified structure would drive the resonant networks symmetrically, which would be expected to increase operational efficiency at least by preventing saturation of the magnetic elements.
In re claim 22, Das (see Fig. 9A), as modified, discloses a third winding (see the alternative resonant units in Figs. 13B, which may be used in the conversion circuit as taught at [0108]: any of the structures have a winding which would form the third winding as part of, or connected to, the first resonant unit in Fig. 9A) electrically connected in series to the first resonant unit (C901) and coupled between the first connection node (between S901, S902) and the first midpoint (between S909 and L901); and
a seventh winding (as part of another resonant unit forming the third resonant unit, again selected from those of Fig. 13B as explained above) electrically connected in series to the third resonant unit (e.g., C902 of Fig. 9A, which may be seen to correspond to 102C01 or 101C01 of Fig. 26A, which was used as the basis for modifying Fig. 9A as explained above) and coupled between the fourth connection node (which would be in the second switching circuit, e.g., between 102S01 and 102S02 of Fig. 26A when used to modify Fig. 9A) and the second midpoint (which is between the second rectifying switch and second winding from Fig. 9A as explained from claim 1).
Conclusion
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/FRED E FINCH III/Primary Examiner, Art Unit 2838
1 The applied reference has a common applicant and one or more common joint inventors with the instant application. Based upon the earlier effectively filed date of the reference, it constitutes prior art under 35 U.S.C. 102(a)(2). This rejection under 35 U.S.C. 102(a)(2) might be overcome by: (1) a showing under 37 CFR 1.130(a) that the subject matter disclosed in the reference was obtained directly or indirectly from the inventor or a joint inventor of this application and is thus not prior art in accordance with 35 U.S.C. 102(b)(2)(A); (2) a showing under 37 CFR 1.130(b) of a prior public disclosure under 35 U.S.C. 102(b)(2)(B) if the same invention is not being claimed; or (3) a statement pursuant to 35 U.S.C. 102(b)(2)(C) establishing that, not later than the effective filing date of the claimed invention, the subject matter disclosed in the reference and the claimed invention were either owned by the same person or subject to an obligation of assignment to the same person or subject to a joint research agreement.
2 In applying the broadest reasonable interpretation to claims 4-6 and 8, it is assumed that m=2, x=1 and k=1.
3 Based on Applicant’s election of Species XX, claim 8 is being examined by interpreting the other end of the energy storage unit is connected to the second end of the load.
Prosecution Insights