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 .
Election/Restrictions
Applicant’s election without traverse of Species 1 (Figures 1-4) in the reply filed on 04/03/2026 is acknowledged.
Claims 4-6, 14-15, 17 and 20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected Species 2-5, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 04/03/2026.
Claims 1-3, 7, 8-13, 16, 18 and 19 are currently pending to be examined.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 06/27/2024 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Specification
The disclosure is objected to because of the following informalities:
Paragraph 0002, “with emergence” should be changed to “with the emergence”.
Paragraph 0007, line 7, “couping a gate control cirucit” should be changed to “coupling a gate control circuit”.
Paragraph 0022, “the flying capacitor 121” should be changed to “the flying capacitor 12”.
Paragraph 0023, line 7, “volatge” should be changed to “voltage”.
Paragraph 0023, line 9, “capactior” should be changed to “capacitor”.
Paragraph 0026, line 11, “embdoment” should be changed to “embodiment”.
Paragraph 0032, “Referring FIG. 4” should be changed to “Referring to FIG. 4”.
Paragraph 0036, line 5, “a source terminal the switch” should be changed to “a source terminal of the switch”.
Paragraph 0040, “Referring the FIG. 7” should be changed to “Referring to FIG. 7”.
Paragraph 0041, “for illustrated purpose” should be changed to “for illustrative purpose”.
Paragraph 0046, “comverter” should be changed to “converter”.
Paragraph 0047, “may further comprises” should be changed to “may further comprise”.
Appropriate correction is required.
Claim Objections
Claims 2 is objected to because of the following informalities:
Claim 2, line 1, “the first pre-charge circuit” should be changed to “the pre-charge circuit” as that is what was recited in claim 1 which claim 2 depends upon.
Appropriate correction is required.
Claim Rejections
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.
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 1 is rejected under 35 U.S.C. 103 as being unpatentable over Zhang (US 10027223 B1) in view of Balaz (US 2025/0357845 A1) and in further view of Li (US 2020/0067409 A1).
Regarding claim 1, Zhang teaches a switching converter (Figure 4), comprising: an input terminal (Figure 4 Component IN) configured to receive an input voltage (Figure 4 Component Vin); an output terminal configured to provide an output voltage (Figure 4 Component Vout is the output voltage and the terminal where Vout is outputted would be the output terminal); a switching circuit (Figure 4 Component 402) having a first switch device (Figure 4 Component 408-1), a second switch device (Figure 4 Component 408-2), and a third switch device (Figure 4 Component 408-3), wherein a first terminal of the first switch device is coupled to the input terminal (Figure 4 Component 408-1 has a drain terminal coupled to Component Vin through node IN1), and a first terminal of the second switch device is coupled to a second terminal of the first switch device (Figure 4 Component 408-2 has a drain terminal coupled to the source terminal of Component 408-1); a first flying capacitor having a first terminal and a second terminal (Figure 4 Component CF), wherein the first terminal of the first flying capacitor is coupled to the first terminal of the second switch device and the second terminal of the first switch device (Figure 4 Component CF has a top terminal coupled to the drain terminal of Component 408-2 and the source terminal of Component 408-1), and the second terminal of the flying capacitor is coupled to a first terminal of the third switch device (Figure 4 Component CF has a bottom terminal coupled to the source terminal of Component 408-3); an output filter (Figure 4 Component CM; Col. 8 Lines 17-18 “an output buffer capacitor CM”; A buffer output capacitor is known to provide the function of filtering high frequency noise) coupled between the switching circuit and the output terminal (Figure 4 Component CM is coupled between the output terminal and switching circuit because it is coupled between Vout and the source terminal of Component 408-4 which is a part of the switching circuit), wherein the output filter is coupled to a second terminal of the second switch device (Figure 4 Component CM has a top terminal coupled to the source terminal of Component 408-2); and a pre-charge circuit (Figure 4 Component 404) coupled to the input terminal (Figure 4 Component 404 is coupled to Component IN), and is configured to charge the first flying capacitor via a first pre-charge switch (Figure 4 Component 416) during start-up of the switching converter (Col. 8 Lines 24-35 “The auxiliary bypass circuit 404 is arranged parallel to the switching transistor 408-1 and includes an transistor 416 and an impedance element 418. In this manner, the auxiliary bypass circuit 404 provides an auxiliary circuit path through the impedance element 418 to charge the capacitors when the auxiliary soft-charge bypass circuit is activated and the switching transistor 408-1 is deactivated”; Col. 1 Lines 19-21 “The disclosure relates generally to switched capacitor devices and, more particularly, to start up charging of such capacitor devices in switching power converter circuits.”), wherein the first pre-charge switch has a first terminal coupled to the input terminal (Figure 4 Component 416 has a drain terminal coupled to Component IN through Component 418), a second terminal (Figure 4 Component 416 source terminal) and a control terminal (Figure 4 Component 416 gate terminal), and wherein the pre-charge circuit is configured to get a voltage at the second terminal during start-up of the switching converter (Figures 5A and 5B show the operational modes of the converter; Figure 5A shows a start-up operation which shows that Component 212, which is Component 416 from Figure 4, is configured to generate a voltage at the source terminal during start-up operations; Col. 3 Lines 39-41).
Zhang does not teach wherein the output filter comprises a magnetic device; and wherein the pre-charge circuit is configured to get a voltage at the second terminal of the first pre-charge switch to follow a voltage at the control terminal of the first pre-charge switch.
Hasan teaches a pre-charge circuit (Figure 3), comprising: a pre-charge switch (Figure 3 Component 109 is part of a pre-charge/biasing circuit for generating a voltage for the switching node) wherein the first pre-charge switch has a first terminal (Figure 3 Component 109 Drain Terminal), a second terminal (Figure 3 Component 109 Source Terminal), and a control terminal (Figure 3 Component 109 Gate Terminal), wherein the pre-charge circuit is configured to get a voltage at the second terminal of the first pre-charge switch to follow a voltage at the control terminal of the first pre-charge switch (Figure 3 shows a clamp circuit, Component 206a, provide a clamp voltage that is applied to the gate of Component 109; Capacitor 104 is coupled between the gate of Component 109 and node 110/111, which are coupled to the source terminal of Component 109; Through this capacitive coupling, variations in the clamp voltage applied to the gate of Component 109 are coupled to node 110/111 such that the voltage at node 110/111 follows/tracks the voltage applied to the gate of Component 109; Accordingly, the pre-charge circuit of Balaz is configured so that a voltage at the second terminal of Component 109 follows a voltage at the control terminal of Component 109 via the capacitor Component 104).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the teachings of Zhang to incorporate the gate coupling arrangement taught by Balaz having the charged node track the gate voltage of the pre-charge switch. The advantage of this design is that it enables gradual charging of the node and reducing inrush current and electrical stress on circuit components. Furthermore, the gate-coupling technique of Balaz provides a self-regulating control relationship simplifies the control of the pre-charge switch and reduces the need for more complex control circuitry.
Li teaches a switching converter (Figure 2A), comprising: an input terminal configured to receive an input voltage (Figure 2A Component Vin); an output terminal configured to provide an output voltage (Figure 2A Component Vo); a switching circuit having a first, second, third and fourth switch (Figure 2A Components Q1-Q4); a flying capacitor (Figure 2A Component Cfly); an output filter coupled between the switching circuit and the output terminal (Figure 2A Component 240), wherein the output filter comprises a magnetic device coupled to a second terminal of the second switch device (Figure 2A Component Ls).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the teachings of Zhang to incorporate an inductor in the output filter in combination with the capacitor as taught by Li. The advantage of this modification offers better noise rejection and more precise/stable filtering.
Allowable Subject Matter
Claims 2, 3, 7 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:
Regarding claim 2, none of the prior art, made of record, singularly or in combinations, teaches or fairly suggests wherein the first pre-charge circuit is configured to automatically stop charging the first flying capacitor based on the input voltage after the start-up is complete.
Regarding claim 3, none of the prior art, made of record, singularly or in combinations, teaches or fairly suggests wherein the pre-charge circuit comprises: a first resistor having a first terminal and a second terminal, wherein the first terminal of the first resistor is coupled to the input terminal, and the second terminal of the first resistor is coupled to the control terminal of the first pre-charge switch; and a second resistor having a first terminal and a second terminal, wherein the first terminal of the second resistor is coupled to the second terminal of the first resistor and the control terminal of the first pre-charge switch; wherein the first terminal of the first flying capacitor is further coupled to the second terminal of the first pre-charge switch and the second terminal of the first flying capacitor is further coupled to the second terminal of the second resistor.
Regarding claim 7, none of the prior art, made of record, singularly or in combinations, teaches or fairly suggests wherein the switching circuit further comprises: a fourth switch device, wherein a first terminal of the fourth switch device is coupled to the second terminal of the second switch device, and a second terminal of the fourth switch device is coupled to a second terminal of the third switch device and a reference ground.
Claims 8-13, 16 and 18-19 are allowed.
The following is an examiner’s statement of reasons for allowance:
Regarding claim 8, the closest prior references that could be located in the search conducted are the references used to reject independent claim 1. However, none of the prior art, made of record, singularly or in combinations, teaches or fairly suggests wherein the pre-charge circuit is configured to charge the flying capacitor via partially turning on a pre-charge switch during start-up of the switching converter.
Claims 9-13 and 16 depend upon claim 8 therefore are also allowed.
Claims 14-15 and 17 are part of a non-elected species, however, since claim 8 was a generic claim and has been found allowable claims 14-15 and 17 are in condition for allowance based on a rejoinder due to the allowance of a generic claim.
Regarding claim 18, the closest prior references that could be located in the search conducted are the references used to reject independent claim 1. However, none of the prior art, made of record, singularly or in combinations, teaches or fairly suggests coupling a gate control circuit to the input terminal, wherein the gate control circuit is configured to provide a gate control signal to control the pre-charge switch; and partially turning on the pre-charge switch via the gate control circuit to charge the flying capacitor during start-up of the switching converter.
Claim 19 depend upon claim 18 therefore is also allowed.
Claim 20 is part of a non-elected species, however, since claim 18 was a generic claim and has been found allowable claim 20 is in condition for allowance based on a rejoinder due to the allowance of a generic claim.
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Liu (US 2025/0158513 A1) teaches a pre-bias voltage control circuit includes a flying capacitor and a voltage controlled current source. The voltage sensor is used to generate a sensed capacitor voltage according to a capacitor voltage across the flying capacitor, and includes an inverting input terminal coupled to the flying capacitor, a non-inverting input terminal coupled to the flying capacitor, and an output terminal for outputting the sensed capacitor voltage. The voltage controlled current source is used to charge and discharge the flying capacitor, and includes a reference terminal for receiving a reference voltage, an input terminal coupled to the output terminal of the voltage sensor, a current output terminal coupled to the flying capacitor, and a current return terminal coupled to the flying capacitor. The voltage controlled current source generates a source current to charge the flying capacitor when the sensed capacitor voltage falls below the reference voltage.
Tarroboiro (US 2022/0302827 A1) teaches a power converter that includes a switching circuit coupled to a capacitor and further coupled to a regulated power supply node via an inductor. The switching circuit is configured to magnetize the inductor, using the capacitor, in response to activation of a first control signal, and further configured to charge the capacitor, using an input power supply, in response to activation of a second control signal. A control circuit is configured to activate the first control signal based on a comparison of a first threshold value and a current flowing in the inductor. The control circuit is further configured to activate the second control signal based on a comparison of a second threshold value and the current flowing in the inductor.
Hasan (US 9954353 B2) teaches a pre-charge circuit is disclosed for a vehicle including a battery and a load. The pre-charge circuit includes a time delay circuit configured to, in response to receiving power from the battery, generate a first voltage. The first voltage increases from a first value toward a second value. The pre-charge circuit includes a switch control circuit configured to, in response to the first voltage, provide a second voltage that follows the first voltage. The pre-charge circuit includes a switching circuit configured to selectively connect the battery to the load based on the second voltage and disconnect the load from the battery in response to the second voltage reaching a predetermined threshold value. The pre-charge circuit includes an output circuit configured to restrict an amount of power and inrush current that is provided from the battery to the load through the switching circuit.
Liu (US 2023/0047446 A1) teaches a flying capacitor converter which has a pre-charge process wherein the switches 411 and 421 are partially turned on to slow down the pre-charging speed of the flying capacitors 414 and 424. Once the voltages across capacitors 414 and 424 reach the pre-determined value, the switches 411 and 421 are turned off while the switches 413 and 423 are still on.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Shahzeb K. Ahmad whose telephone number is (571)272-0978. The examiner can normally be reached Monday - Friday 8 A.M. to 5 P.M..
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Thienvu V. Tran can be reached at 571-270-1276. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Shahzeb K Ahmad/Examiner, Art Unit 2838
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