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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 2/4/2025, 9/11/2025 and 10/2/2025 have been considered by the examiner.
Drawings
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, a comparison result of a voltage difference between a drain and a source of the main power transistor and a preset voltage value, as in claim 1, 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
The title of the invention is not descriptive. A new title is required that is clearly indicative of the invention to which the claims are directed.
A title such as the following is suggested: Control of a power converter with reduced switching loss.
Claim Objections
Claims 1-20 are objected to because of the following informalities:
in claim 1, line 9, “for preset duration” should be ‘for a preset duration’.
in claim 5, line 9, “for preset duration” should be ‘for a preset duration’.
in claim 11, line 9, “for preset duration” should be ‘for a preset duration’.
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.
Claim 14 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. Applicant has impermissibly combined embodiments of the asymmetric half-bridge with the active clamp flyback converters that were not intended to be used together. Independent claim 5 requires the topology of the asymmetric half-bridge flyback converter while dependent claim 14 contradicts the previously claimed limitations of the independent claim by requiring the active clamp flyback converter topology. The claim is indefinite when interpreted in light of the specification because the distinct topologies cannot be used together making it unclear which is claimed.
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) 1, 5 ,7-8, 11-13, 15 and 17-18 are rejected under 35 U.S.C. 103 as being unpatentable over Yang (US 2022/0271676) in view of Xu (US 2019/0013802).
With respect to claim 1, Yang discloses a control circuit (Fig. 11 200) of a power supply module, wherein the power supply module comprises an asymmetric half-bridge flyback converter circuit (Fig. 11 10,M2-M3) and a rectifier circuit (Fig. 11 M1), the asymmetric half-bridge flyback converter circuit comprises a main power transistor (Fig. 11 M2), an auxiliary power transistor (Fig. 11 M3), and a transformer (Fig. 11 10), the rectifier circuit is configured to receive power supplied by the transformer, and the main power transistor and the auxiliary power transistor are alternately turned on and off (Fig. 12 S2,S3); and the control circuit is configured to: after the auxiliary power transistor is turned off (Fig. 12 TC falling edge) and before the main power transistor is turned on (Fig. 12 TB rising edge), control the rectifier circuit to discharge (Fig. 12 IP during TA) to the transformer for preset duration (Fig. 12 TA); and after the rectifier circuit stops discharging (Fig. 12 TA ends) to the transformer, control the main power transistor to be turned on (Fig. 12 TB occurs Td1 later). Yang does not require the main power transistor to be turned on based on a comparison result of a voltage difference between a drain and a source of the main power transistor and a preset voltage value.
Xu discloses to control the main power transistor to be turned on (Fig. 3 t1) based on a comparison result (Fig. 6 600) of a voltage difference (Fig. 3 Vds) between a drain and a source of the main power transistor and a preset voltage value (Fig. 2 VTH). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to implement to control the main power transistor to be turned on based on a comparison result of a voltage difference between a drain and a source of the main power transistor and a preset voltage value, in order to guarantee the turn on with low loss at the zero voltage condition.
With respect to claim 5, Yang in view of Xu make obvious a power supply module (Fig. 11 900), comprising: an asymmetric half-bridge flyback converter circuit, configured to receive an input voltage (Fig. 11 VIN) as set forth above. See claim 1 for additional details
With respect to claim 7, Yang in view of Xu make obvious the power supply module according to claim 5, wherein the rectifier circuit (Fig. 11 M1,20) comprises a switching transistor (Fig. 11 M1) and a capacitor (Fig. 11 20).
With respect to claim 8, Yang in view of Xu make obvious the power supply module according to claim 7, wherein when the control circuit controls the switching transistor to be turned on (Fig. 12 start T1), the rectifier circuit discharges (Fig. 12 IP) to the transformer; and when the control circuit controls the switching transistor to be turned off (Fig. 12 TA ends), the rectifier circuit stops (Fig. 11 M1 open) discharging to the transformer.
With respect to claim 11, Yang in view of Xu make obvious the power supply module according to claim 5, wherein the transformer comprises a primary-side winding (Fig. 11 NP) and a secondary-side winding (Fig. 11 NS), and the secondary-side winding supplies power to a load (Fig. 11 load connected to VO) through the rectifier circuit (Fig. 11 M1,70,75,80).
With respect to claim 12, Yang in view of Xu make obvious the power supply module according to claim 11, wherein the rectifier circuit (Fig. 11 M1,70,75,80) comprises a switching transistor (Fig. 11 70) and a capacitor (Fig. 11 80), and wherein a drain of the switching transistor is connected to one terminal of the secondary-side winding (Fig. 11 terminal NS-70), a source of the switching transistor is connected to one terminal (Fig. 11 ground terminal) of the capacitor, and the other terminal of the secondary-side winding is connected to the other terminal (Fig. 11 output terminal VO) of the capacitor; and when the control circuit controls the switching transistor to be turned on, the rectifier circuit discharges to the transformer (Fig. 11 IS discharges) through the secondary-side winding.
With respect to claim 13, Yang in view of Xu make obvious the power supply module according to claim 5, wherein the drain of the main power transistor (Fig. 11 M2) is configured to receive the input voltage (Fig. 11 VIN), the source of the main power transistor is connected to a drain of the auxiliary power transistor (Fig. 11 M3), a source of the auxiliary power transistor is connected to a reference ground (Fig. 11 ground symbol), and a primary-side winding (Fig. 11 NP) of the transformer is connected in parallel between the drain and the source of the auxiliary power transistor through a resonant capacitor (Fig. 11 20).
With respect to claim 15, Yang in view of Xu make obvious an electronic device (Fig. 11 900), comprising: an asymmetric half-bridge flyback converter circuit, configured to receive an input voltage (Fig. 11 VIN) as set forth above. See claim 1 for additional details.
With respect to claim 17, Yang in view of Xu make obvious the electronic device according to claim 15, wherein the rectifier circuit (Fig. 11 M1,20) comprises a switching transistor (Fig. 11 M1) and a capacitor (Fig. 11 20).
With respect to claim 18, Yang in view of Xu make obvious electronic device according to claim 15, wherein the rectifier circuit comprises a switching transistor (Fig. 11 M1), and wherein when the control circuit controls the switching transistor to be turned on (Fig. 12 start TA), the rectifier circuit discharges (Fig. 12 IP) to the transformer; and when the control circuit controls the switching transistor to be turned off (Fig. 12 TA ends), the rectifier circuit stops (Fig. 11 M1 open) discharging to the transformer.
Claim(s) 9 and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Yang (US 2022/0271676) in view of Xu (US 2019/0013802) and further in view of Sun (CN 114285288).
With respect to claim 9, Yang in view of Xu make obvious the power supply module as set forth above, and remain silent as how to power the power supply module. It was well known before the effective filing date of the claimed invention to power a power supply module from an auxiliary winding.
Sun discloses wherein the power supply module comprises an auxiliary winding (Fig. 1 Na), the auxiliary winding is coupled to the transformer (Fig. 1 T1), and the auxiliary winding supplies power (Fig. 1 Vcc) to the control circuit through the rectifier circuit (Fig. 1 D2,D3,C3). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to implement wherein the power supply module comprises an auxiliary winding, the auxiliary winding is coupled to the transformer, and the auxiliary winding supplies power to the control circuit through the rectifier circuit, (the rectifier circuit including M1 of Yang and C3,D2,D3,C4 of Sun). The reason for doing so was to power the internal voltage of the power supply module.
With respect to claim 19, Yang in view of Xu and Sun make obvious the electronic device according as set forth above. See claim 9 for additional details.
Allowable Subject Matter
Claims 2-4, 6, 10, 16 and 20 are 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. The following is a statement of reasons for the indication of allowable subject matter:
With respect to claim 2, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, control the main power transistor to be turned on based on a comparison result of a voltage difference between a drain and a source of the main power transistor and a preset voltage value, and wherein the control circuit is configured to: control, based on a comparison result of the voltage difference between the drain and the source of the main power transistor and an input voltage, the rectifier circuit to start discharging to the transformer for the preset duration.
With respect to claim 3, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, control the main power transistor to be turned on based on a comparison result of a voltage difference between a drain and a source of the main power transistor and a preset voltage value, and wherein the power supply module further comprises an auxiliary winding, the auxiliary winding is coupled to the transformer, and the auxiliary winding is configured to supply power to the control circuit through the rectifier circuit and the control circuit is configured to: control the rectifier circuit to discharge to the transformer within the preset duration through the auxiliary winding.
With respect to claim 4, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, control the main power transistor to be turned on based on a comparison result of a voltage difference between a drain and a source of the main power transistor and a preset voltage value, and wherein the transformer comprises a primary-side winding and a secondary-side winding, and the secondary-side winding is configured to supply power to a load through the rectifier circuit; and the control circuit is configured to: control the rectifier circuit to discharge to the transformer within the preset duration through the secondary-side winding.
With respect to claim 6, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, wherein the control circuit is configured to: control, based on a comparison result of the voltage difference between the drain and the source of the main power transistor and the input voltage, the rectifier circuit to start discharging to the transformer for the preset duration.
With respect to claim 10, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, control the main power transistor to be turned on based on a comparison result of a voltage difference between a drain and a source of the main power transistor and a preset voltage value, and wherein the rectifier circuit comprises a switching transistor and a capacitor, and wherein a drain of the switching transistor is connected to one terminal of the auxiliary winding, a source of the switching transistor is connected to one terminal of the capacitor, and the other terminal of the auxiliary winding is connected to the other terminal of the capacitor; and when the control circuit controls the switching transistor to be turned on, the rectifier circuit discharges to the transformer through the auxiliary winding.
With respect to claim 16, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, wherein the control circuit is configured to: control, based on a comparison result of the voltage difference between the drain and the source of the main power transistor and the input voltage, the rectifier circuit to start discharging to the transformer for the preset duration.
With respect to claim 20, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, control the main power transistor to be turned on based on a comparison result of a voltage difference between a drain and a source of the main power transistor and a preset voltage value, and wherein the electronic device comprises an auxiliary winding, and wherein a drain of the switching transistor is connected to one terminal of the auxiliary winding, a source of the switching transistor is connected to one terminal of the capacitor, and the other terminal of the auxiliary winding is connected to the other terminal of the capacitor; and when the control circuit controls the switching transistor to be turned on, the rectifier circuit discharges to the transformer through the auxiliary winding.
The aforementioned limitations in combination with all remaining limitations of the respective claims are believed to render the aforementioned indicated claim and any dependent claims thereof patentable over the art of record.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Koo (US 10,790,753) discloses reduced switching losses with use of a rectifier circuit. Qian (CN 110611431A) discloses sensing the drain-source voltage of the main switch in a flyback converter. Song (US 2018/0294735) discloses reducing switching loss by using an auxiliary switch.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to HARRY RAYMOND BEHM whose telephone number is (571)272-8929. The examiner can normally be reached M-F: 8-5 EST.
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/HARRY R BEHM/Primary Examiner, Art Unit 2838
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