DETAILED ACTION
1. This action is in response to the application filed on 8/5/26.
Notice of Pre-AIA or AIA Status
2. 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
3. Applicant’s election without traverse of Invention I and Species 4 (figures 1-2 and 8-13), claims 1-13 in the reply filed on 8/5/26 is acknowledged.
Drawings
4. 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,
“at least one ceramic electrical insulator” (in claim 5);
“at least one fiber optic link to transfer logic signals” (in claim 19);
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.
Claim Rejections - 35 USC § 102
5. 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)(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.
6. Claims 1, 7, and 11 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Chen (A Bidirectional Isolated Dual-Phase-Shift Variable-Frequency Series Resonant Dual-Active-Bridge GaN AC–DC Converter. Cited in the IDS filed on 9/9/24).
Regarding claim 1: Chen discloses (i.e. figures 1-5) a multi-level switching power converter system (i.e. system of figure 1) comprising: a multi-level switching converter arranged as a tri-active bridge (TAB) switching converter (i.e. converter of figure 1), the TAB switching converter comprising:
a transformer (i.e. Transformer) comprising a first winding (i.e. primary winding) and a second winding (i.e. secondary winding);
a first switching stage (i.e. unfolding bridge stage) comprising a first set of switches (i.e. Si1-4) arranged as a first H-bridge and controlled by a first set of switching signals (i.e. signal to Si1-4) to convert between an AC voltage (i.e. Vac) and a first DC voltage (i.e. DC output of first stage);
a second switching stage (i.e. stage of switches S1a-2b) comprising a second set of switches (i.e. S1a-S2b) arranged as a second H-bridge and controlled by a second set of switching signals (i.e. signals for S1a-S2b), the second switching stage (i.e. stage of switches S1a-2b) comprising a first switching node (i.e. node for S2a-S2b) between a first pair of the second set of switches (i.e. S2a, S2b) and a second switching node (i.e. node for S1a, S1b) between a second pair of the second set of switches (i.e. S1a, S1b), the first and second switching nodes (i.e. node for S2a-S2b) (i.e. node for S1a, S1b) being directly coupled to the first winding (i.e. primary winding) to one of provide or receive a first voltage (i.e. voltage of primary winding) associated with the first winding (i.e. primary winding) in response to one of the first DC voltage (i.e. DC output of first stage) and a second DC voltage (i.e. VDC output); and
a third switching stage (i.e. stage includes switches S3-6) comprising a third set of switches (i.e. S3-6) arranged as a third H-bridge and controlled by a third set of switching signals (i.e. signals to S3-6), the third switching stage (i.e. stage includes switches S3-6) comprising a third switching node (i.e. node for S3, S4) between a first pair of the third set of switches (i.e. S3, S4) and a fourth switching node (i.e. node for S5, S6) between a second pair of the third set of switches (i.e. S5, S6), the third and fourth switching nodes (i.e. node for S3, S4) (i.e. node for S5, S6) being directly coupled to the second winding (i.e. secondary winding) to one of provide or receive a second voltage (i.e. VDC output) associated with the second winding (i.e. secondary winding) in response to the other of the first and second DC voltages (i.e. DC output of first stage) (i.e. VDC output); and
a switch controller (i.e. controller for switches of figure 1) configured to generate the first (i.e. signal to Si1-4), second (i.e. signals for S1a-S2b), and third (i.e. signals to S3-6) sets of switching signals, to provide at least one of the first (i.e. signal to Si1-4), second (i.e. signals for S1a-S2b), and third (i.e. signals to S3-6) sets of switching signals at a variable frequency (i.e. fs) that varies as a function of a power metric (i.e. power metric from Vac) associated with a frequency of the AC voltage (i.e. frequency of AC voltage), to provide a variable phase shift (i.e. figure 3: see phase shift between signals Vgs1-6) between the second (i.e. signals for S1a-S2b) and third sets of switching signals (i.e. signals to S3-6), and to provide a variable phase shift (i.e. figure 3: phase shift of signals Vgs3-6 and phase 3, 4, 5, 6) between the respective switching signals (i.e. signals to S3-6) that control one switch in each of the first and second pairs (i.e. S3, S4) of at least one of the second and third sets (i.e. S3-6) of switches relative to another one switch (i.e. S5 or S6) in each of the first and second pairs (i.e. S5, S6) of the respective at least one of the second and third sets (i.e. S3-6) of switches (i.e. see pages 3316-3322).
Regarding claim 6: (i.e. figures 1-5) wherein the switch controller is configured to vary at least one of the variable frequency (i.e. fs) and the variable phase shift (i.e. phase of 3-6 in figure 3) of the second and third sets of switching signals (i.e. signals for S1a-S2b) (i.e. signals to S3-6) in response to a feedback signal (i.e. see figure 6, signa of change phase angle and control variable) associated with the transformer (i.e. transformer) (i.e. see pages 3316-3322).
Regarding claim 7: (i.e. figures 1-5) further comprising a saturable inductor (i.e. line, or Lin) coupled in series with the first switching stage (i.e. unfolding bridge stage).
Regarding claim 11: (i.e. figures 1-5) wherein at least one of the first, second, and third sets of switches are arranged as metal oxide semiconductor field effect transistor (MOSFET) devices (i.e. see switches of figure 1).
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. Claim 2 is rejected under 35 U.S.C. 102(a)(2) as being anticipated by Chen (A Bidirectional Isolated Dual-Phase-Shift Variable-Frequency Series Resonant Dual-Active-Bridge GaN AC–DC Converter. Cited in the IDS filed on 9/9/24) in views of Herohold (US 20110140824).
Regarding claim 2: Chen discloses the limitation of the claim(s) as discussed above, but does not specifically disclose the transformer is arranged as a planar transformer comprising the first winding, the second winding, and a magnetic core, wherein the first winding is formed as metallic traces on at least one first printed circuit board (PCB) and the second winding is formed as metallic traces on at least one second PCB, the magnetic core being formed around at least a portion of the first and second PCBs.
Herohold disclose the transformer (i.e. figures 1-2) is arranged as a planar transformer (i.e. 1) comprising the first winding (i.e. 4), the second winding (i.e. 5), and a magnetic core (i.e. 1, 1’), wherein the first winding (i.e. 4) is formed as metallic traces (i.e. traces of 4) on at least one first printed circuit board (PCB) (i.e. 2) and the second winding (i.e. 5) is formed as metallic traces (i.e. traces of 5) on at least one second PCB (i.e. 3), the magnetic core (i.e. 1, 1’) being formed around at least a portion of the first (i.e. 2) and second PCBs (i.e. 3). 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 Chen’s invention with the transformer as disclose by Herohold, because the planar transformer can be produced at a low cost and is compact, but is still suitable for connection to intrinsically safe operating circuits is implemented by at least one gap being asymmetrically split on the first printed circuit board and the second printed circuit board.
9. Claim 4 is rejected under 35 U.S.C. 102(a)(2) as being anticipated by Chen (A Bidirectional Isolated Dual-Phase-Shift Variable-Frequency Series Resonant Dual-Active-Bridge GaN AC–DC Converter. Cited in the IDS filed on 9/9/24) in views of Herohold (US 20110140824) and further in views of Ackermann et al. (US 20080297300).
Regarding claim 4: Chen discloses the limitation of the claim(s) as discussed above, but does not specifically disclose the planar transformer comprises at least one liquid cooling tube provided proximal to at least one of the first and second windings.
Ackermann et al. disclose the planar transformer comprises at least one liquid cooling tube (i.e. cooling medium) provided proximal to at least one of the first and second windings (i.e. ¶ 24).
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 Chen’s invention with the transformer as disclose by Ackermann et al. to improve cooling of the winding.
10. Claim 5 is rejected under 35 U.S.C. 102(a)(2) as being anticipated by Chen (A Bidirectional Isolated Dual-Phase-Shift Variable-Frequency Series Resonant Dual-Active-Bridge GaN AC–DC Converter. Cited in the IDS filed on 9/9/24) in views of Herohold (US 20110140824) and further in views of Downing et al. (US 6278353).
Regarding claim 5: Chen discloses the limitation of the claim(s) as discussed above, but does not specifically disclose at least one ceramic electrical insulator configured to electrically isolate the first winding and the second set of switches from the second winding and the third set of switches.
Downing et al. disclose (i.e. figure 10) a transformer device (i.e. 130) comprising at least one ceramic electrical insulator (i.e. 132) configured to electrically isolate the first winding (i.e. 134) from the second winding (i.e. 144).
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 Chen’s invention with the transformer as disclose by Downing et al. in order to have at least one ceramic electrical insulator configured to electrically isolate the first winding and the second set of switches from the second winding and the third set of switches, because it accommodates the flow of liquid coolant that carries heat away from the PM transformer 130 during operation.
11. Claim 8 is rejected under 35 U.S.C. 102(a)(2) as being anticipated by Chen (A Bidirectional Isolated Dual-Phase-Shift Variable-Frequency Series Resonant Dual-Active-Bridge GaN AC–DC Converter. Cited in the IDS filed on 9/9/24) in views of Herohold (US 20110140824) in views of Bala et al. (US 20200336068).
Regarding claim 8: Chen discloses the limitation of the claim(s) as discussed above, but does not specifically disclose each of the first and second DC voltages is at least 750 VDC, wherein the AC voltage is between approximately 500 VAC and 2 kVAC.
Bala et al. disclose a power supply comprising the DC voltages is at least 750 VDC, wherein the AC voltage is between 380-480 VAC (i.e. ¶ 02 and 42).
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 Chen’s invention with the power supply as disclose by Bala et al. to have the first and second DC voltages is at least 750 VDC, because it increases the power supply efficiency.
In addition, it would have been obvious to one having ordinary skill in the art at the time the invention was made to modified Chen and Bala et al.’s invention to have each of the first and second DC voltages is at least 750 VDC, wherein the AC voltage is between approximately 500 VAC and 2 kVAC to increase the power conversion efficiency, since it has been held that where the general conditions of a claim are discloses in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
12. Claim 9 is rejected under 35 U.S.C. 102(a)(2) as being anticipated by Chen (A Bidirectional Isolated Dual-Phase-Shift Variable-Frequency Series Resonant Dual-Active-Bridge GaN AC–DC Converter. Cited in the IDS filed on 9/9/24) in views of Herohold (US 20110140824) and further in views of ji et al. (US 20190157980).
Regarding claim 9: Chen discloses the limitation of the claim(s) as discussed above, but does not specifically disclose comprising at least one fiber optic link to transfer logic signals between the switch controller and at least one of the first, second, and third switching stages.
ji et al. disclose a power converter (i.e. figure 4) comprising at least one fiber optic link to transfer logic signals between the switch controller (i.e. 9) and at least one of the first (i.e. 18), second, and third switching stages (i.e. ¶ 36).
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 Chen’s invention with the power converter as disclose by ji et al., because it allows operation at high frequency with high efficiency.
13. Claim 11 is rejected under 35 U.S.C. 102(a)(2) as being anticipated by Chen (A Bidirectional Isolated Dual-Phase-Shift Variable-Frequency Series Resonant Dual-Active-Bridge GaN AC–DC Converter. Cited in the IDS filed on 9/9/24) in views of Herohold (US 20110140824) and further in views of Divan et al. (US 20240297598).
Regarding claim 11: Chen disclose the limitation of the claim(s) as discussed above, but does not specifically disclose at least one of the first, second, and third sets of switches are arranged as silicon carbide (SiC) transistor devices.
Divan et al. disclose a power supply comprising at least one of the first, second, and third sets of switches are arranged as silicon carbide (SiC) transistor devices (i.e. ¶ 113).
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 Chen’s invention with the power supply as disclose by Divan et al., because the advent of Silicon Carbide MOSFETs (SiC-MOSFET) has reduced the impact of tail-current associated turn-off loss for the IGBTs and leads to improved efficiency.
14. Claim 12 is rejected under 35 U.S.C. 102(a)(2) as being anticipated by Chen (A Bidirectional Isolated Dual-Phase-Shift Variable-Frequency Series Resonant Dual-Active-Bridge GaN AC–DC Converter. Cited in the IDS filed on 9/9/24) in views of Herohold (US 20110140824) and furth in view of Geng et al. (US 20240355702).
Regarding claim 12: Chen disclose (i.e. figures 1-5) at least one of the first, second, and third sets of switches are arranged as transistor devices the limitation of the claim(s) as discussed above, but does not specifically disclose a heat spreader comprising a base and a plurality of legs that are adapted to be coupled to a mounting surface on which the transistor device is provided; an interposer that is adapted to be coupled to the mounting surface; and a transistor bare die comprising a gate terminal, a source terminal, and a drain terminal.
Geng et al. disclose an integrated circuit packages (i.e. figures 3-4 and 8-11) a heat spreader (i.e. 402) comprising a base (i.e. base of 402) and a plurality of legs (i.e. 408 on each side) that are adapted to be coupled to a mounting surface (i.e. 204) on which the transistor device (i.e. show in figure 9) is provided; an interposer (i.e. 304) that is adapted to be coupled to the mounting surface (i.e. 204); and a transistor bare die (i.e. 302 and figure 9) comprising a gate terminal, a source terminal, and a drain terminal (i.e. terminals of transistor show in figure 9) (i.e. ¶ 26-40 and 59).
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 Chen’s invention with the packages as disclose by Geng et al., because there is a desire to keep the package size small while still increasing the IO capabilities.
15. Claim 13 is rejected under 35 U.S.C. 102(a)(2) as being anticipated by Chen (A Bidirectional Isolated Dual-Phase-Shift Variable-Frequency Series Resonant Dual-Active-Bridge GaN AC–DC Converter. Cited in the IDS filed on 9/9/24).
Regarding claim 13: (i.e. figures 1-5) a voltage converter circuit comprising a plurality of the TAB switching converter (i.e. see figure 1(b), phase A, B, and C) of claim 1, the voltage converter circuit being configured to convert between the AC voltage (i.e. Vac) and the first DC voltage (i.e. DC output of first stage), except for at an amplitude ratio greater than one. It would have been obvious to one having ordinary skill in the art at the time of the invention was made to modify the Chen’s invention in order to have an amplitude ratio greater than one to increase the power supply efficiency. Since, it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980).
Allowable Subject Matter
16. Claim 3 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Conclusion
17. 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.
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/Nguyen Tran/Primary Examiner, Art Unit 2838
