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.
Response to Arguments
Applicant's arguments filed 4/28/2026 with respect to amended claim 1 have been fully considered but they are not persuasive.
In response to Applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which Applicant relies (i.e., without waiting for or verifying any specific responsive action or confirmation signal, there is no disclosed step where it listens for a confirmation signal from the transformer) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993). Applicant states Chen makes a decision to sleep at time T3. Examiner contends the decision to sleep is made at time T1, and entering the sleep state is delayed until T3 to provide time to provide the communication to the primary side at T2. Examiner believes the claim as written does not require the argued verifying a confirmation signal, instead requiring a secondary-side controller electrically connected to the secondary-side circuit, the secondary-side controller configured to acquire an output signal of a secondary-side winding in the transformer and to enter the sleep mode when the output signal is a predefined first output signal. These limitations are satisfied by the secondary-side controller detecting the frequency of the SYN signal is less than the standby frequency threshold at time T1. Examiner interprets GCS at the first control signal, STS as the first request signal, SYN as the first output signal and the switching frequency of SYN less than the standby threshold as the predefined first output signal. When the switching frequency drops below the standby threshold at T1, the secondary-side controller is configured to enter the sleep mode by the primary side signaling the secondary through the transformer 108 as required by the claim. Examiner finds no limitations in the claim preventing interpreting the predefined first output signal as the frequency of SYN < threshold at T1 before entering sleep at time T3, nor that verifying a confirmation signal must be performed.
Applicant argues Chen does not disclose the first output signal is produced by the first control signal turning on or off the first switch in the primary-side circuit to cause a voltage change in the secondary-side winding of the transformer. Yet Chen discloses wherein the first output signal is produced by the first control signal (Fig. 2 SYN turns on in response to GCS off and SYN turns off in response to GCS turn on) turning on or off the first switch in the primary-side circuit to cause a voltage change (Fig. 1 switching the primary causes a voltage change in the secondary) in the secondary-side winding of the transformer. Examiner believes the amended claim still reads upon the Chen reference and the rejections have been maintained below. Applicant's arguments filed 4/28/2026 with respect to claim 13 have been fully considered but they are not persuasive.
In response to Applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which Applicant relies (i.e., without waiting for or verifying any specific responsive action or confirmation signal, there is no disclosed step where it listens for a confirmation signal from the transformer) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993). Examiner does not read the claim language to require the closed-loop handshaking argued by Applicant. Examiner reminds Applicant that the argued steps are not the actual claim language recited in claim 13 and Examiner must give the recited claim language the broadest reasonable interpretation consistent with the specification. Method claim 13 specifies no order in which the steps must be completed and Examiner must interpret the recited steps and order in the broadest reasonable sense. The secondary controller detector, as shown in Figure 1 202, monitors the signal SYN and enters the sleep mode when the secondary-side controller detects the frequency of SYN is too low. The first output signal is the SYN signal and thus performs the step of 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 at T1). The claim does not require or claim verifying or listening for confirmation signal. The first control signal (Fig. 2 GCS) performs the step for turning on or off a first switch (Fig. 1 104) in the primary-side circuit in a predefined manner, that is such that GCS issues the predefined last pulse at T3. Examiner believes all recited claim limitations of claim 13 are met by the Chen reference and the rejection has been maintained below.
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. 1 212) an output signal (Fig. 1 SYN) 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 is produced by the first control signal (Fig. 2 SYN turns on in response to GCS off and SYN turns off in response to GCS turn on) turning on or off the first switch in the primary-side circuit to cause a voltage change (Fig. 1 switching the primary causes a voltage change in the secondary) in the secondary-side winding of the transformer.
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. See the action dated 1/30/2026 for the statement of reasons for the indication of allowable subject matter:
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Khamesra (US 2020/0412231) discloses a primary receiving communications from secondary side and the primary responding to the secondary through the main transformer. Hara (US 2020/0169179) discloses acknowledging communications.
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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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.
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/HARRY R BEHM/Primary Examiner, Art Unit 2838
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