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
Acknowledgment is made of applicant's claim for foreign priority based on an application filed in China on 5/22/2023. It is noted, however, that applicant has not filed a certified copy of the CN 202310581657.0 application as required by 37 CFR 1.55.
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 CIRCUIT FOR OPERATION OF AN ISOLATED SWITCHING-MODE CONVERTER IN A SLEEP MODE.
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.
Claim(s) 1-2, 8 and 13 are rejected under 35 U.S.C. 102a1 as being anticipated by Chen (US 2018/0323722).
With respect to claim 1, Chen discloses a control circuit (Fig. 1 200,300) for controlling an isolated switching-mode converter (Fig. 1 100), the isolated switching-mode converter comprising a primary-side circuit (Fig. 1 PRI), a secondary-side circuit (Fig. 1 SEC) and a transformer (Fig. 1 108) coupled between the primary-side circuit and the secondary-side circuit, the control circuit comprising: a primary-side controller (Fig. 1 300) electrically connected to the primary-side circuit, the primary-side controller configured to generate, when receiving (Fig. 1 302) a first request signal (Fig. 2 STS) indicative of a request to enter a sleep mode (Fig. 2 300 Standby mode), a first control signal (Fig. 1 GCS) for turning on or off a first switch (Fig. 1 104) in the primary-side circuit in a predefined manner (Fig. 2 pulse from T3 to T4) and thereby causing the primary-side controller to enter the sleep mode (Fig. 2 300 Standby Mode at T4), wherein the first control signal is predefined (Fig. 1 304 generates predefined GCS pulse); and a secondary-side controller (Fig. 1 200) electrically connected to the secondary-side circuit, the secondary-side controller configured to acquire (Fig. 1 SYN) an output signal (Fig. 1 voltage of 108) of a secondary-side winding (Fig. 1 108) in the transformer and to enter the sleep mode (Fig. 2 Standby mode at T3) when the output signal is a predefined first output signal (Fig. 2 frequency SYN < threshold), the first output signal responding to the first control signal (Fig. 2 SYN turns on in response to GCS off and SYN turns off in response to GCS turn on).
With respect to claim 2, Chen discloses the control circuit of claim 1, wherein the primary-side controller comprises a first receiver circuit (Fig. 1 306), a first logic processing circuit (Fig. 1 304 GCS duration generation circuit) and a first driver circuit (Fig. 1 304 driver of GCS), the first receiver circuit configured to receive (Fig. 1 302) the first request signal (Fig. 2 STS) and provide the first request signal to the first logic processing circuit, the first logic processing circuit configured to generate a drive signal (Fig. 2 drive of pulse from T3 to T4) based on the first request signal and provide the drive signal to the first driver circuit, the first driver circuit configured to generate the first control signal (Fig 1 GCS output from 305) based on the drive signal.
With respect to claim 8, Chen discloses the control circuit of claim 1, wherein the secondary-side controller comprises a detection circuit (Fig. 1 202) and a second logic processing circuit (Fig. 1 204), the detection circuit configured to acquire (Fig. 1 212) the output signal (Fig. 1 SYN) of the secondary-side winding and provide the output signal to the second logic processing circuit, the second logic processing circuit configured to instruct the secondary-side controller to enter the sleep mode (paragraph 13) when the output signal is the predefined first output signal.
With respect to claim 13, Chen discloses a control method for an isolated switching-mode converter, the isolated switching-mode converter comprising a primary-side circuit (Fig. 1 PRI), a secondary-side circuit (Fig. 1 SEC) and a transformer (Fig. 1 108) coupled between the primary-side circuit and the secondary-side circuit, the control method comprising: providing a first request signal (Fig. 1 STS) indicative of a request to enter a sleep mode to a primary-side controller (Fig. 1 300), which then generates, based on the first request signal, a predefined first control signal (Fig. 2 GCS from T3 to T4) for turning on or off a first switch (Fig.1 104) in the primary-side circuit in a predefined manner and thereby causing the primary-side controller to enter the sleep mode (Fig. 2 300 Standby mode at T4); turning on or off the first switch based on the first control signal (Fig. 1 GCS) to cause a voltage change (Fig. 1 voltage SYN) in a secondary-side winding (Fig. 1 108) in the transformer, thereby producing a predefined first output signal (Fig. 1 frequency SYN); and entry of the secondary-side controller into the sleep mode (Fig. 2 200 Standby mode at T3) when the secondary-side controller detects the first output signal (Fig. 2 frequency SYN < threshold).
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) 3-4 and14 are rejected under 35 U.S.C. 103 as being unpatentable over Chen (US 2018/0323722) in view of Chuang (US 2008/0298095).
With respect to claim 3, Chen discloses the control circuit of claim 1 as set forth above and remains silent as to regulating the operating supply voltage of the primary controller. It was well known before the effective filing date of the invention to regulate the operating supply voltage of a primary controller.
Chuang discloses wherein the primary-side controller (Fig. 3 308) is also configured to detect a power supply voltage (Fig. 3 VCC) and enter, when the power supply voltage drops below a first threshold voltage (Fig. 3 VCC_L), a partial wake-up mode in which the first switch is turned on (Fig. 4 PWM from t1 to t2) at least once to increase the power supply voltage to a level (Fig. 4 VCC_H) not lower than the first threshold voltage, and wherein the primary-side controller is partially woken up to increase the power supply voltage (Fig. 4 Vcc) and again enters the sleep mode (Fig. 4 after t2) when the power supply voltage reaches a second threshold voltage (Fig. 4 VCC_H). 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 primary-side controller is also configured to detect a power supply voltage and enter, when the power supply voltage drops below a first threshold voltage, a partial wake-up mode in which the first switch is turned on at least once to increase the power supply voltage to a level not lower than the first threshold voltage, and wherein the primary-side controller is partially woken up to increase the power supply voltage and again enters the sleep mode when the power supply voltage reaches a second threshold voltage, in order to reduce the power consumption during standby, yet ensure the primary controller has a sufficient operating voltage to prevent undervoltage lockout.
With respect to claim 4, Chen in view of Chuang make obvious the control circuit of claim 3 as set forth above, wherein the isolated switching-mode converter further comprises an auxiliary winding (Chuang Fig. 3 Laux) and a power supply capacitor (Chuang Fig. 3 C2), the auxiliary winding coupled to the transformer (Fig. 3 306), one end of the auxiliary winding and one end of the power supply capacitor both connected to a ground terminal (Fig. 3 ground symbol) for the primary-side circuit, the other end of the power supply capacitor coupled to the other end of the auxiliary winding through a diode (Fig. 3 301), and wherein the primary-side controller comprises an undervoltage lockout circuit (Fig. 3 UVLO), a first logic processing circuit (Fig. 3 318) and a first driver circuit (Fig. 3 308 driver of SW), the undervoltage lockout circuit electrically connected (Fig. 3 VCC) to the other end of the power supply capacitor and configured to acquire a voltage across the power supply capacitor as the power supply voltage, the first logic processing circuit configured to generate, when the power supply voltage drops below the first threshold voltage (Fig. 4 VCC_L), a drive signal (Fig. 4 PWM) based on an associated comparison and provide the drive signal to the first driver circuit, the first driver circuit configured to generate, based on the drive signal, an ON signal (Fig. 3 gate signal SW) for turning on the first switch (Fig. 3 SW) to allow the power supply capacitor to be charged to increase the power supply voltage (Fig. 4 Vcc rises after t2) to a level (Fig. 4 VCC_H) not lower than the first threshold voltage.
With respect to claim 14, Chen in view of Chuang make obvious the method as set forth above. See claim 3 for additional details.
Claim(s) 5-7 and 15-16 are rejected under 35 U.S.C. 103 as being unpatentable over Chen (US 2018/0323722) in view of Rehm (US 5,949,660).
With respect to claim 5, Chen discloses the control circuit of claim 1 as set forth above, and remains silent as to the secondary-side controller being coupled to a protocol chip, which was well known before the effective filing date of the claimed invention.
Rehm discloses a protocol device (Fig. 1 14) coupled to the secondary-side controller (Fig 1 20), the protocol device configured to provide the secondary-side controller with a first instruction signal (Fig. 1 P) which instructs entering the sleep mode; and an isolator (Fig. 1 Tr2) coupled between the primary-side controller and the secondary-side controller. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to implement a protocol chip coupled to the secondary-side controller, the protocol chip configured to provide the secondary-side controller with a first instruction signal which instructs entering the sleep mode; and an isolator coupled between the primary-side controller and the secondary-side controller, wherein the secondary-side controller receives the first instruction signal, utilizes the isolator to produce the first request signal and provides the first request signal to the primary-side controller, in order to interface with the user in a cost effective manner.
With respect to claim 6, Chen in view of Rehm make obvious the control circuit of claim 5, wherein the secondary-side controller (Fig. 1 200) is also configured to maintain a second switch (Fig. 1 102) in the secondary-side circuit in an off state (Fig. 2 200 Standby mode) based on the first instruction signal, thereby operating the secondary-side circuit in an asynchronous rectification mode.
With respect to claim 7, Chen in view of Rehm make obvious the control circuit of claim 6, wherein the secondary-side controller comprises a second receiver circuit (Fig. 1 202), a second logic processing circuit (Fig. 2 206,204) and a second driver circuit (Fig. 2 driver of gate 102 not shown), the second receiver circuit configured to receive the first instruction signal (in combination as in Rehm Fig. 1 P) and provide the first instruction signal to the second logic processing circuit, the second logic processing circuit configured to generate a drive signal based on the first instruction signal and provide the drive signal to the second driver circuit, the second driver circuit configured to generate, based on the drive signal, an OFF signal for maintaining the second switch in the off state (Fig. 1 synchronous rectifier 102 off during standby).
With respect to claims 15-16, Chen in view of Rehm make obvious the method as set forth above. See claims 5-6, respectively, for additional details.
Claim(s) 9-10 and 17-18 are rejected under 35 U.S.C. 103 as being unpatentable over Chen (US 2018/0323722) in view of Rehm (US 5,949,660) and further in view of Chuang (US 2008/0298095).
With respect to claim 9, Chen discloses the control circuit of claim 1 as set forth above, and remains silent as to the secondary-side controller being coupled to a protocol chip, which was well known before the effective filing date of the claimed invention.
Rehm discloses a protocol device (Fig. 1 14) coupled to the secondary-side controller (Fig. 1 20), the protocol device configured to provide the secondary-side controller with a second instruction signal (Fig. 1 P) which instructs exiting the sleep mode. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to implement a protocol chip coupled to the secondary-side controller, the protocol chip configured to provide the secondary-side controller with a second instruction signal which instructs exiting the sleep mode, in order to interface with the user in a cost effective manner.
With respect to claim 10, Chen in view of Rehm make obvious the control circuit of claim 9, wherein the secondary-side controller (Fig. 1 200) is configured to acquire the output signal (Fig. 1 voltage 108) of the secondary-side winding (Fig. 1 108) in the transformer and to exit (Fig. 9B 920) the sleep mode when the output signal is a predefined second output signal (Fig. 9B 914) and when the secondary-side winding has received the second instruction signal (in combination, as in Fig. 9B 918, exits when receives command to exit); the control circuit further comprises an isolator (Fig. 1 106) coupled between the primary-side controller and the secondary-side controller; the secondary-side controller is configured to receive (in combination, Chen Fig. 1 200 receives instructions as 20 of Rehm) the second instruction signal, utilize the isolator to produce a second request signal and provide the second request signal (Fig. 5 LS) to the primary-side controller; and the primary-side controller is also configured to exit (in combination, as in Fig. 5 300 Standby mode to Normal mode) the sleep mode when receiving the second request signal. Chen remains silent as to implementing a partial wake-up mode.
Chuang discloses wherein the primary-side controller (Fig. 3 308) is also configured to receive a power supply voltage (Fig. 3 VCC) and enter, when the power supply voltage drops below a first threshold voltage (Fig. 4 VCC_L), a partial wake-up mode in which the first switch (Fig. 3 ) is turned on (Fig. 4 PWM) to increase the power supply voltage to a level (Fig. 4 VCC_H) not lower than the first threshold voltage. 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 primary-side controller is also configured to receive a power supply voltage and enter, when the power supply voltage drops below a first threshold voltage, a partial wake-up mode in which the first switch is turned on to increase the power supply voltage to a level not lower than the first threshold voltage, and wherein the primary-side controller is woken up when receiving the second request signal while being partially awakened, thus the primary-side controller completely exits the sleep mode, in order to ensure the primary controller has a sufficient operating voltage to prevent undervoltage lockout, and to transition to normal operating mode when receiving the command to prepare for the higher loading required by the load.
With respect to claims 17-18, Chen in view of Chuang and Rehm make obvious the method as set forth above. See claims 9-10 for additional details.
Claim(s) 12 is rejected under 35 U.S.C. 103 as being unpatentable over Chen (US 2018/0323722) in view of Cui (US 2019/0319480).
With respect to claim 12, Chen discloses the control circuit of claim 1, and wherein the isolated switching-mode converter further comprises an auxiliary winding (Fig. 1 auxiliary winding powering 300) and a power supply capacitor (Fig. 1 primary side bulk capacitor), the auxiliary winding coupled to the transformer, one end of the auxiliary winding and one end of the power supply capacitor both connected to a ground terminal (Fig. 1 primary side ground symbol) for the primary-side circuit, the other end of the power supply capacitor coupled to the other end of the auxiliary winding through a diode (Fig. 1 diode rectifying auxiliary winding to 300 operating power supply), the power supply capacitor providing the power supply voltage to the primary-side controller. Chen does not require a partial wake-up mode with operation at a predetermined switching frequency.
Cui discloses wherein the primary-side controller (Fig. 2 130) is also configured to enter a partial wake-up mode at a predetermined switching frequency (paragraph 16, minimum switching frequency), in which the first switch is turned on at least once (turned on each period of the minimum switching frequency) to increase a power supply voltage (Fig. 1 VCC) of the primary-side controller. 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 primary-side controller is also configured to enter a partial wake-up mode at a predetermined switching frequency, in which the first switch is turned on at least once to increase a power supply voltage of the primary-side controller, in order to maintain sufficient power to maintain the operating supply voltage of the primary-side controller.
Allowable Subject Matter
Claims 11 and 19-20 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 11, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, a protocol chip coupled to the secondary-side controller, the protocol chip configured to provide the secondary-side controller with a second instruction signal which instructs exiting the sleep mode, wherein the secondary-side controller is also configured to receive the second instruction signal that instructs exiting the sleep mode and to turn on a second switch in the secondary-side circuit based on the second instruction signal, and wherein the primary-side controller exits the sleep mode when sensing a change in a signal from the secondary-side winding in the transformer.
With respect to claim 19, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily,
providing a second instruction signal which instructs exiting the sleep mode by a protocol chip to the secondary-side controller; turning on a second switch in the secondary-side circuit by the secondary-side controller based on the second instruction signal, thereby causing a change in a signal from the secondary-side winding in the transformer; and exit of the primary-side controller from the sleep mode when the primary-side controller senses the change in the signal from the secondary-side winding in the transformer.
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
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.
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, Thienvu 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.
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.
/HARRY R BEHM/Primary Examiner, Art Unit 2838