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 .
Claims 1-20 are pending.
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 6-7, 12-14, and 19-20 and are rejected under 35 U.S.C. 102(a)(1) as being anticipated by BONDADE et al. USPGPUB 2018/0219547 (hereinafter “BONDADE”).
Regarding claim 6, BONDADE teaches an apparatus, configured to: provide a control signal having a programmed transition time ([Abstract] “The apparatus further includes a switch driver coupled to the peak detector circuit and configured to adjust a control signal to the switch responsive to the detected peak amplitude”);
determine a value of voltage oscillations at a switch node of a power converter under control of the control signal ([Abstract] “The apparatus also includes a peak detector circuit coupled to the ring node of the voltage divider circuit and configured to detect a peak amplitude of the ring voltage. The apparatus further includes a switch driver coupled to the peak detector circuit and configured to adjust a control signal to the switch responsive to the detected peak amplitude”, Paragraph [0026] “FIG. 2 further includes a peak detector 130 coupled to the ring node 101. Ringing occurs as energy stored in parasitic inductances dissipates, causing the ring voltage at the drain of low-side switch 140 and thus at ring node 101 to produce a damping high oscillation signal. As described further below, the peak detector 130 outputs a DC voltage capturing peak AC amplitude during this damping high oscillation period. The peak detector 130 further couples to a switch driver 135 through a connection wire 131 and the switch driver 135 is configured to adjust a control signal asserted to the gate 141 of low- side switch 140”, and Paragraph [0016], wherein examiner interpreted peak detector detecting peak amplitude of ring voltage coupled to switch driver as determining a value of voltage oscillations at a switch node of a power converter under control of the control signal); and
modify the transition time of the control signal based on a period of the voltage oscillations (Paragraph [0016] “adjusting the control signal can adjust the switching speed of the switch, which, in turn, adjusts (e.g., reduce) the magnitude of the ringing. In some embodiments, as described further below, the magnitude of the ringing can also be adjusted by altering a start time of a ringing mitigation phase when the switch transitions between on/off states”, wherein examiner interpreted adjusting control signal by altering start time of ringing mitigation phase as modifying the transition time of the control signal based on a period of the voltage oscillations).
Regarding claim 7, BONDADE teaches wherein the transition time is one of a rise time or a fall time (Paragraph [0016] “adjusting the control signal can adjust the switching speed of the switch, which, in turn, adjusts (e.g., reduce) the magnitude of the ringing. In some embodiments, as described further below, the magnitude of the ringing can also be adjusted by altering a start time of a ringing mitigation phase when the switch transitions between on/off states”, wherein examiner interpreted switch transitions between on/off states as transition time being one of a rise time or a fall time).
Regarding claim 12, BONDADE teaches wherein determining the value of the voltage oscillations includes determining that the voltage oscillations are at a first peak value at a first time and determining that the voltage oscillations are at a second peak value less than the first peak value at a second time, and wherein modifying the transition time of the control signal includes setting the transition time to equal a difference between the second time and the first time (Paragraph [0036], and Paragraph [0037] “ the digital controller 220 can further adjust the control signal by activating a specific number of high-side segmented switches 235, so as to adjust the start of time T2, of phase 2—resulting in an adjusted (e.g., reduced) peak AC ring amplitude. For example, assume the low-side switch 140 takes 20 ns to complete the negative dV/dt phase (transition time T1), from time 0, while the ringing mitigation phase lasts for 30 ns, leading to 50V in peak AC ring amplitude, as a consequence of the system parasitic. To reduce the amplitude of the ring, the digital controller 220 can be configured to start phase 2 even before the negative dV/dt phase has completed, thereby effectively reducing the time T1, while keeping T2 constant. This consequently results in smaller peak AC ring amplitude”, wherein examiner interpreted adjusting start time to reduce peak AC ring amplitude including starting before negative dv/dt phase as setting a transition time equal to the difference between second time and first time).
Regarding claim 13, BONDADE teaches wherein the apparatus is configured to begin a timer responsive to determining that the voltage oscillations are at the first peak value at the first time, and stop the timer responsive to determining that the voltage oscillations are at the second peak value at the second time, and wherein a count value of the timer is the difference between the second time and the first time (Paragraph [0037] “ the digital controller 220 can further adjust the control signal by activating a specific number of high-side segmented switches 235, so as to adjust the start of time T2, of phase 2—resulting in an adjusted (e.g., reduced) peak AC ring amplitude. For example, assume the low-side switch 140 takes 20 ns to complete the negative dV/dt phase (transition time T1), from time 0, while the ringing mitigation phase lasts for 30 ns, leading to 50V in peak AC ring amplitude, as a consequence of the system parasitic. To reduce the amplitude of the ring, the digital controller 220 can be configured to start phase 2 even before the negative dV/dt phase has completed, thereby effectively reducing the time T1, while keeping T2 constant. This consequently results in smaller peak AC ring amplitude”, wherein examiner interpreted the time T2 being the phase for reducing the amplitude of ringing as the time difference between the first and second peak values).
Regarding claim 14, BONDADE teaches a system, comprising: a power converter (Paragraph [0017] “The example circuit system shown in FIG. 1 is a half-bridge configuration of a converter 30 usable to drive a high powered load connected to a line 70”); and
a controller coupled to the power converter (Paragraph [0019] “As discussed above, the example converter shown in FIG. 1 employs a separate ring amplitude adjustment circuit to adjust the corresponding control signal of each switch present in the circuit system”, wherein examiner interpreted converter employing ring amplitude circuit to adjust control signal as a controller coupled to the power converter), wherein the controller is configured to:
provide a control signal having a programmed transition time to the power converter (Paragraph [0016] “At least some of the embodiments disclosed herein are directed to a ring amplitude sensor circuit which is configured to measure a peak AC amplitude of a ringing voltage and, in response to the measured peak AC amplitude, the ring amplitude sensor is configured to adjust a control signal driving a switch. Because the magnitude of the control signal impacts switching speed, and further because switching speed impacts switching loss, EMI noise and ringing, adjusting the control signal can adjust the switching speed of the switch, which, in turn, adjusts (e.g., reduce) the magnitude of the ringing. In some embodiments, as described further below, the magnitude of the ringing can also be adjusted by altering a start time of a ringing mitigation phase when the switch transitions between on/off states”, and Paragraph [0019-0020], wherein examiner interpreted switching low-side switch, and high-side switch on/off as providing control signal having a programmed transition time to the power converter, wherein examiner interpreted switching on//off as control signal having programmed transition time);
determine a value of voltage oscillations at a switch node of power converter under control of the control signal ([Abstract] “The apparatus also includes a peak detector circuit coupled to the ring node of the voltage divider circuit and configured to detect a peak amplitude of the ring voltage. The apparatus further includes a switch driver coupled to the peak detector circuit and configured to adjust a control signal to the switch responsive to the detected peak amplitude”, Paragraph [0026] “FIG. 2 further includes a peak detector 130 coupled to the ring node 101. Ringing occurs as energy stored in parasitic inductances dissipates, causing the ring voltage at the drain of low-side switch 140 and thus at ring node 101 to produce a damping high oscillation signal. As described further below, the peak detector 130 outputs a DC voltage capturing peak AC amplitude during this damping high oscillation period. The peak detector 130 further couples to a switch driver 135 through a connection wire 131 and the switch driver 135 is configured to adjust a control signal asserted to the gate 141 of low- side switch 140”, and Paragraph [0016], wherein examiner interpreted peak detector detecting peak amplitude of the ring voltage as determining a value of voltage oscillations at a switch node of power converter under the control signal); and
modify the transition time of the control signal based on a reciprocal of a frequency of the voltage oscillations (Paragraph [0016] “adjusting the control signal can adjust the switching speed of the switch, which, in turn, adjusts (e.g., reduce) the magnitude of the ringing. In some embodiments, as described further below, the magnitude of the ringing can also be adjusted by altering a start time of a ringing mitigation phase when the switch transitions between on/off states”, wherein examiner interpreted adjusting control signal by altering start time of ringing mitigation phase as modifying the transition time of the control signal based on a period of the voltage oscillations, wherein reciprocal of a frequency is a period, therefore, this includes the reciprocal of a frequency of voltage oscillations).
Regarding claim 19, BONDADE teaches wherein determining the value of the voltage oscillations includes determining that the voltage oscillations are at a first peak value at a first time and determining that the voltage oscillations are at a second peak value less than the first peak value at a second time, and wherein modifying the transition time of the control signal includes setting the transition time to equal a difference between the second time and the first time (Paragraph [0036], and Paragraph [0037] “ the digital controller 220 can further adjust the control signal by activating a specific number of high-side segmented switches 235, so as to adjust the start of time T2, of phase 2—resulting in an adjusted (e.g., reduced) peak AC ring amplitude. For example, assume the low-side switch 140 takes 20 ns to complete the negative dV/dt phase (transition time T1), from time 0, while the ringing mitigation phase lasts for 30 ns, leading to 50V in peak AC ring amplitude, as a consequence of the system parasitic. To reduce the amplitude of the ring, the digital controller 220 can be configured to start phase 2 even before the negative dV/dt phase has completed, thereby effectively reducing the time T1, while keeping T2 constant. This consequently results in smaller peak AC ring amplitude”, wherein examiner interpreted adjusting start time to reduce peak AC ring amplitude including starting before negative dv/dt phase as setting a transition time equal to the difference between second time and first time).
Regarding claim 20, BONDADE teaches wherein the system is configured to begin a timer responsive to determining that the voltage oscillations are at the first peak value at the first time, and stop the timer responsive to determining that the voltage oscillations are at the second peak value at the second time, and wherein a count value of the timer is the difference between the second time and the first time (Paragraph [0037] “ the digital controller 220 can further adjust the control signal by activating a specific number of high-side segmented switches 235, so as to adjust the start of time T2, of phase 2—resulting in an adjusted (e.g., reduced) peak AC ring amplitude. For example, assume the low-side switch 140 takes 20 ns to complete the negative dV/dt phase (transition time T1), from time 0, while the ringing mitigation phase lasts for 30 ns, leading to 50V in peak AC ring amplitude, as a consequence of the system parasitic. To reduce the amplitude of the ring, the digital controller 220 can be configured to start phase 2 even before the negative dV/dt phase has completed, thereby effectively reducing the time T1, while keeping T2 constant. This consequently results in smaller peak AC ring amplitude”, wherein examiner interpreted the time T2 being the phase for reducing the amplitude of ringing as the time difference between the first and second peak values).
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim 1-4, 8-10, 15-16, and 18 are rejected under 35 U.S.C. 103 as being unpatentable over BONDADE et al. USPGPUB 2018/0219547 (hereinafter “BONDADE”), in view of Twelkemeijer et al. USP 11557960 (hereinafter “Twelkemeijer”).
Regarding claim 1, BONDADE teaches a method, comprising: programming a rise time of a power converter control signal to a first value; programming a fall time of the power converter control signal to a second value (Paragraph [0017] “The example circuit system shown in FIG. 1 is a half-bridge configuration of a converter 30 usable to drive a high powered load connected to a line 70. In some embodiments, the converter 30 adjusts (e.g., reduces or increases) ringing, as described further below, occurring during on/off transition of both high-side switch 85 and low-side switch 140”, wherein examiner interpreted converter adjusting ringing as programming a rise time of a power converter control signal to a first value, and programming a fall time of the power converter control signal to a second value, wherein examiner interpreted increasing as programming a rise time, and reducing as a fall time); and
executing a tuning operation loop including: determining a first peak value of voltage ringing at a switch node of a power converter controlled according to the power converter control signal (Paragraph [0016] “At least some of the embodiments disclosed herein are directed to a ring amplitude sensor circuit which is configured to measure a peak AC amplitude of a ringing voltage and, in response to the measured peak AC amplitude, the ring amplitude sensor is configured to adjust a control signal driving a switch”, wherein examiner interpreted peak AC amplitude of a ringing voltage measured by the ring amplitude sensor as determining a first peak value of voltage ringing at a switch node of a power converter controlled according to the power converter control signal);
incrementing the rise time and the fall time each by a programmed amount (Paragraph [0036-0037] describes the transition times of switches to adjust control signal at different time phases as including incrementing the rise time and the fall time each by a programmed amount);
BONDADE does not explicitly teach determining a second peak value of voltage ringing at the switch node; comparing the first peak value to the second peak value; and responsive to the second peak value being less than the first peak value, repeating execution of the tuning operation loop.
However, Twelkemeijer teaches determining a second peak value of voltage ringing at the switch node (FIG. 8, and Col. 15, Line 29-40 “FIG. 8 is a state machine diagram of a valley switching state and a not valley switching state with internal processes within each state. A controller transitions 806 from a valley switching state 802 to a not valley switching state 804 when a ringing amplitude measure, such as Vaux, falls below an amplitude threshold, such as Vdemag_high. Similarly, the controller transitions 808 from the not valley switching state 804 to the valley switching state 802 when a ringing amplitude measure, such as Vaux, rises below an amplitude threshold, such as Vdemag_high_hys. The two thresholds may be the same or different and there may be multiple tests, such as 4 tests, before a transition is made”, wherein examiner interpreted ringing amplitude thresholds as determining a second peak value of voltage ringing at a switch node);
comparing the first peak value to the second peak value (FIG. 8, and Col. 15, Line 29-40 “FIG. 8 is a state machine diagram of a valley switching state and a not valley switching state with internal processes within each state. A controller transitions 806 from a valley switching state 802 to a not valley switching state 804 when a ringing amplitude measure, such as Vaux, falls below an amplitude threshold, such as Vdemag_high. Similarly, the controller transitions 808 from the not valley switching state 804 to the valley switching state 802 when a ringing amplitude measure, such as Vaux, rises below an amplitude threshold, such as Vdemag_high_hys. The two thresholds may be the same or different and there may be multiple tests, such as 4 tests, before a transition is made”, wherein examiner interpreted comparing peak ringing amplitude to an amplitude threshold as comparing first peak value to the second peak value, wherein examiner interpreted the various comparing various peak amplitudes with various thresholds in multiple ringing cycles as including comparing one peak ringing value to another peak ringing value as described with respect to valley switching); and
responsive to the second peak value being less than the first peak value, repeating execution of the tuning operation loop (Col. 15, Line 52-64 “With each new power phase, the controller determines the start of the next cycle. At 814, the end of the actual cycle time, tps, is detected by first determining if the ringing amplitude, as determined through Vaux, or another measure is below the low threshold. If so, then at 816, a new ringing cycle is detected by determining if the ringing amplitude is above the medium threshold. If not, then a new ringing cycle is not detected and the process returns to the initial conditions at 810. The state remains in valley switching. If the ringing amplitude exceeds the medium threshold, then a new ringing cycle is detected. The controller is then ready to test the ringing amplitude for valley switching”, Col. 15, Line 65 – Col. 16 Line 3 “At 818, if the ringing amplitude stays below the high threshold and Vaux<Vdemag_low, then valley switching is disabled. The criteria at 806 are met and the state transitions to the not valley switching state 804. If the ringing amplitude is above the high threshold, then the controller remains in the valley switching state 802”, wherein examiner interpreted the comparison of ringing amplitude to a threshold, which indicates whether it is a new ringing cycle or not as including determining that the second peak value is less than first peak value, and in response repeating the execution of the tuning operation loop).
BONDADE, and Twelkemeijer are analogous art because they are from the same field of endeavor and contain overlapping structural and functional similarities. They both relate to power converters.
Therefore, at the time of effective filing date, it would have been obvious to a person of ordinary skill in the art to modify the above method of determining peak value of voltage ringing, as taught by BONDADE, and incorporating comparing peak voltage ringing values, as taught by Twelkemeijer.
One of ordinary skill in the art would have been motivated to improve minimizing switching losses in the converter and improve overall efficiency, as suggested by Twelkemeijer (see Col. 1, Line 25-37).
Regarding claim 2, BONDADE, and Twelkemeijer teaches all of the features with respect to claim 1 as outlined above.
Twelkemeijer further teaches wherein responsive to the second peak value not being less than the first peak value, the method includes: decrementing the incremented rise time and fall time; and controlling the power converter to perform switching according to the power converter control signal having the rise time and fall time (FIG. 8, Col. 15, Line 29-38 “FIG. 8 is a state machine diagram of a valley switching state and a not valley switching state with internal processes within each state. A controller transitions 806 from a valley switching state 802 to a not valley switching state 804 when a ringing amplitude measure, such as Vaux, falls below an amplitude threshold, such as Vdemag_high. Similarly, the controller transitions 808 from the not valley switching state 804 to the valley switching state 802 when a ringing amplitude measure, such as Vaux, rises below an amplitude threshold, such as Vdemag_high_hys”, [Abstract] “Adaptive enabling and disabling is described for valley switching in a power factor correction boost converter. In one example, a boost converter control system includes an amplitude detector to receive an amplitude signal from a boost converter that is related to ringing of the boost converter output. The amplitude detector determines the ringing amplitude. A valley switching controller compares the ringing amplitude to a first high amplitude threshold when valley switching is enabled and generates a valley switching disable signal if the ringing amplitude is below the first high amplitude threshold”, wherein examiner interpreted when ringing amplitude falls below a threshold as second peak value not being less than the first peak value, and wherein examiner interpreted valley switching as decrementing incremented rise time and fall time, and controlling power converter to switch according to the power converter control signal having a rise time and fall time).
Regarding claim 3, BONDADE, and Twelkemeijer teaches all of the features with respect to claim 1 as outlined above.
BONDADE further teaches wherein the programmed amount is less than each of the rise time and the fall time (Paragraph [0036] “As discussed above in FIG. 1, there can be a transition from a very high voltage of 1000 V to ground when the low-side switch 140 is turned on and this transition isn't instantaneous and occurs with time. In some embodiments, the turn on time of the low- side switch 140 can be divided into three phases—negative dV/dt transition time T1 as phase 1, ring mitigation time T2 as phase 2 and complete turn on time T3 as phase 3. For example, the time T1 can be defined as the time taken by the low-side switch 140 during negative dV/dt transition. The time T2 can be the time during which high oscillation signal (ringing) is damped and the time T3 can be time when the low-side switch 140 is driven to be completely turned on”, wherein examiner interpreted turning on switch in phases to includes the programmed amount to be less than each of the rise time and fall time).
Regarding claim 4, BONDADE, and Twelkemeijer teaches all of the features with respect to claim 1 as outlined above.
BONDADE further teaches wherein modifying the rise time and the fall time of the power converter control signal based on a measured peak value of voltage ringing at the switch node reducing electromagnetic interference radiated by the power converter (Paragraph [0016] “At least some of the embodiments disclosed herein are directed to a ring amplitude sensor circuit which is configured to measure a peak AC amplitude of a ringing voltage and, in response to the measured peak AC amplitude, the ring amplitude sensor is configured to adjust a control signal driving a switch. Because the magnitude of the control signal impacts switching speed, and further because switching speed impacts switching loss, EMI noise and ringing, adjusting the control signal can adjust the switching speed of the switch, which, in turn, adjusts (e.g., reduce) the magnitude of the ringing. In some embodiments, as described further below, the magnitude of the ringing can also be adjusted by altering a start time of a ringing mitigation phase when the switch transitions between on/off states”, wherein examiner interpreted adjusting control signal based on peak amplitude of ringing to reduce EMI noise and switching losses as modifying the rise time and the fall time of the power converter control signal based on a measured peak value of voltage ringing at the switch node reducing electromagnetic interference radiated by the power converter).
Regarding claim 8, BONDADE teaches wherein to determine the value of voltage oscillations and modify the transition time of the control signal, the apparatus is configured to implement a tuning operation loop including: determining a first peak value of the voltage oscillations (Paragraph [0016] “At least some of the embodiments disclosed herein are directed to a ring amplitude sensor circuit which is configured to measure a peak AC amplitude of a ringing voltage and, in response to the measured peak AC amplitude, the ring amplitude sensor is configured to adjust a control signal driving a switch”, wherein examiner interpreted peak AC amplitude of a ringing voltage measured by the ring amplitude sensor as determining a first peak value of the voltage oscillations);
incrementing the transition time by a programmed amount (Paragraph [0036-0037] describes the transition times of switches to adjust control signal at different time phases as incrementing the transition time by a programmed amount).
BONDADE does not explicitly teach determining a second peak value of the voltage oscillations; comparing the first peak value to the second peak value; responsive to the second peak value being less than the first peak value, repeating execution of the tuning operation loop; and responsive to the second peak value not being less than the first peak value, decrementing the transition time by the programmed amount.
However, Twelkemeijer teaches determining a second peak value of the voltage oscillations (FIG. 8, and Col. 15, Line 29-40 “FIG. 8 is a state machine diagram of a valley switching state and a not valley switching state with internal processes within each state. A controller transitions 806 from a valley switching state 802 to a not valley switching state 804 when a ringing amplitude measure, such as Vaux, falls below an amplitude threshold, such as Vdemag_high. Similarly, the controller transitions 808 from the not valley switching state 804 to the valley switching state 802 when a ringing amplitude measure, such as Vaux, rises below an amplitude threshold, such as Vdemag_high_hys. The two thresholds may be the same or different and there may be multiple tests, such as 4 tests, before a transition is made”, wherein examiner interpreted ringing amplitude thresholds as determining a second peak value of the voltage oscillations);
comparing the first peak value to the second peak value (FIG. 8, and Col. 15, Line 29-40 “FIG. 8 is a state machine diagram of a valley switching state and a not valley switching state with internal processes within each state. A controller transitions 806 from a valley switching state 802 to a not valley switching state 804 when a ringing amplitude measure, such as Vaux, falls below an amplitude threshold, such as Vdemag_high. Similarly, the controller transitions 808 from the not valley switching state 804 to the valley switching state 802 when a ringing amplitude measure, such as Vaux, rises below an amplitude threshold, such as Vdemag_high_hys. The two thresholds may be the same or different and there may be multiple tests, such as 4 tests, before a transition is made”, wherein examiner interpreted comparing peak ringing amplitude to an amplitude threshold as comparing first peak value to the second peak value, wherein examiner interpreted the various comparing various peak amplitudes with various thresholds in multiple ringing cycles as including comparing the first peak value to the second peak value);
responsive to the second peak value being less than the first peak value, repeating execution of the tuning operation loop (Col. 15, Line 52-64 “With each new power phase, the controller determines the start of the next cycle. At 814, the end of the actual cycle time, tps, is detected by first determining if the ringing amplitude, as determined through Vaux, or another measure is below the low threshold. If so, then at 816, a new ringing cycle is detected by determining if the ringing amplitude is above the medium threshold. If not, then a new ringing cycle is not detected and the process returns to the initial conditions at 810. The state remains in valley switching. If the ringing amplitude exceeds the medium threshold, then a new ringing cycle is detected. The controller is then ready to test the ringing amplitude for valley switching”, Col. 15, Line 65 – Col. 16 Line 3 “At 818, if the ringing amplitude stays below the high threshold and Vaux<Vdemag_low, then valley switching is disabled. The criteria at 806 are met and the state transitions to the not valley switching state 804. If the ringing amplitude is above the high threshold, then the controller remains in the valley switching state 802”, wherein examiner interpreted the comparison of ringing amplitude to a threshold, which indicates whether it is a new ringing cycle or not as including determining that the second peak value is less than first peak value, and in response repeating the execution of the tuning operation loop); and
responsive to the second peak value not being less than the first peak value, decrementing the transition time by the programmed amount (FIG. 8, Col. 15, Line 29-38 “FIG. 8 is a state machine diagram of a valley switching state and a not valley switching state with internal processes within each state. A controller transitions 806 from a valley switching state 802 to a not valley switching state 804 when a ringing amplitude measure, such as Vaux, falls below an amplitude threshold, such as Vdemag_high. Similarly, the controller transitions 808 from the not valley switching state 804 to the valley switching state 802 when a ringing amplitude measure, such as Vaux, rises below an amplitude threshold, such as Vdemag_high_hys”, [Abstract] “Adaptive enabling and disabling is described for valley switching in a power factor correction boost converter. In one example, a boost converter control system includes an amplitude detector to receive an amplitude signal from a boost converter that is related to ringing of the boost converter output. The amplitude detector determines the ringing amplitude. A valley switching controller compares the ringing amplitude to a first high amplitude threshold when valley switching is enabled and generates a valley switching disable signal if the ringing amplitude is below the first high amplitude threshold”, wherein examiner interpreted when ringing amplitude falls below a threshold as second peak value not being less than the first peak value, and wherein examiner interpreted valley switching as decrementing incremented rise time and fall time, and controlling power converter to switch according to the power converter control signal having a rise time and fall time).
BONDADE, and Twelkemeijer are analogous art because they are from the same field of endeavor and contain overlapping structural and functional similarities. They both relate to power converters.
Therefore, at the time of effective filing date, it would have been obvious to a person of ordinary skill in the art to modify the above method of determining peak value of voltage oscillations, as taught by BONDADE, and incorporating comparing peak voltage oscillation values, as taught by Twelkemeijer.
One of ordinary skill in the art would have been motivated to improve minimizing switching losses in the converter and improve overall efficiency, as suggested by Twelkemeijer (see Col. 1, Line 25-37).
Regarding claim 9, BONDADE, and Twelkemeijer teaches all of the features with respect to claim 8 as outlined above.
BONDADE further teaches wherein the programmed amount is less than the transition time (Paragraph [0036] “As discussed above in FIG. 1, there can be a transition from a very high voltage of 1000 V to ground when the low-side switch 140 is turned on and this transition isn't instantaneous and occurs with time. In some embodiments, the turn on time of the low- side switch 140 can be divided into three phases—negative dV/dt transition time T1 as phase 1, ring mitigation time T2 as phase 2 and complete turn on time T3 as phase 3. For example, the time T1 can be defined as the time taken by the low-side switch 140 during negative dV/dt transition. The time T2 can be the time during which high oscillation signal (ringing) is damped and the time T3 can be time when the low-side switch 140 is driven to be completely turned on”, wherein examiner interpreted turning on switch in phases to includes the programmed amount to be less than each of the rise time and fall time).
Regarding claim 10, BONDADE, and Twelkemeijer teaches all of the features with respect to claim 8 as outlined above.
BONDADE further teaches wherein decrementing the transition time based on the determined value of voltage oscillations at the switch node reduces electromagnetic interference radiated by the power converter (Paragraph [0016] “At least some of the embodiments disclosed herein are directed to a ring amplitude sensor circuit which is configured to measure a peak AC amplitude of a ringing voltage and, in response to the measured peak AC amplitude, the ring amplitude sensor is configured to adjust a control signal driving a switch. Because the magnitude of the control signal impacts switching speed, and further because switching speed impacts switching loss, EMI noise and ringing, adjusting the control signal can adjust the switching speed of the switch, which, in turn, adjusts (e.g., reduce) the magnitude of the ringing. In some embodiments, as described further below, the magnitude of the ringing can also be adjusted by altering a start time of a ringing mitigation phase when the switch transitions between on/off states”, wherein examiner interpreted adjusting control signal based on peak amplitude of ringing to reduce EMI noise and switching losses as modifying the rise time and the fall time of the power converter control signal based on a measured peak value of voltage ringing at the switch node reducing electromagnetic interference radiated by the power converter).
Regarding claim 15, BONDADE teaches wherein to determine the value of voltage oscillations and modify the transition time of the control signal, the controller is configured to implement a tuning operation loop including: determining a first peak value of the voltage oscillations (Paragraph [0016] “At least some of the embodiments disclosed herein are directed to a ring amplitude sensor circuit which is configured to measure a peak AC amplitude of a ringing voltage and, in response to the measured peak AC amplitude, the ring amplitude sensor is configured to adjust a control signal driving a switch”, wherein examiner interpreted peak AC amplitude of a ringing voltage measured by the ring amplitude sensor as determining a first peak value of the voltage oscillations);
incrementing the transition time by a programmed amount (Paragraph [0036-0037] describes the transition times of switches to adjust control signal at different time phases as incrementing the transition time by a programmed amount).
BONDADE does not explicitly teach determining a second peak value of the voltage oscillations; comparing the first peak value to the second peak value; responsive to the second peak value being less than the first peak value, repeating execution of the tuning operation loop; and responsive to the second peak value not being less than the first peak value, decrementing the transition time by the programmed amount.
However, Twelkemeijer teaches determining a second peak value of the voltage oscillations (FIG. 8, and Col. 15, Line 29-40 “FIG. 8 is a state machine diagram of a valley switching state and a not valley switching state with internal processes within each state. A controller transitions 806 from a valley switching state 802 to a not valley switching state 804 when a ringing amplitude measure, such as Vaux, falls below an amplitude threshold, such as Vdemag_high. Similarly, the controller transitions 808 from the not valley switching state 804 to the valley switching state 802 when a ringing amplitude measure, such as Vaux, rises below an amplitude threshold, such as Vdemag_high_hys. The two thresholds may be the same or different and there may be multiple tests, such as 4 tests, before a transition is made”, wherein examiner interpreted ringing amplitude thresholds as determining a second peak value of the voltage oscillations);
comparing the first peak value to the second peak value (FIG. 8, and Col. 15, Line 29-40 “FIG. 8 is a state machine diagram of a valley switching state and a not valley switching state with internal processes within each state. A controller transitions 806 from a valley switching state 802 to a not valley switching state 804 when a ringing amplitude measure, such as Vaux, falls below an amplitude threshold, such as Vdemag_high. Similarly, the controller transitions 808 from the not valley switching state 804 to the valley switching state 802 when a ringing amplitude measure, such as Vaux, rises below an amplitude threshold, such as Vdemag_high_hys. The two thresholds may be the same or different and there may be multiple tests, such as 4 tests, before a transition is made”, wherein examiner interpreted comparing peak ringing amplitude to an amplitude threshold as comparing first peak value to the second peak value, wherein examiner interpreted the various comparing various peak amplitudes with various thresholds in multiple ringing cycles as including comparing the first peak value to the second peak value);
responsive to the second peak value being less than the first peak value, repeating execution of the tuning operation loop (Col. 15, Line 52-64 “With each new power phase, the controller determines the start of the next cycle. At 814, the end of the actual cycle time, tps, is detected by first determining if the ringing amplitude, as determined through Vaux, or another measure is below the low threshold. If so, then at 816, a new ringing cycle is detected by determining if the ringing amplitude is above the medium threshold. If not, then a new ringing cycle is not detected and the process returns to the initial conditions at 810. The state remains in valley switching. If the ringing amplitude exceeds the medium threshold, then a new ringing cycle is detected. The controller is then ready to test the ringing amplitude for valley switching”, Col. 15, Line 65 – Col. 16 Line 3 “At 818, if the ringing amplitude stays below the high threshold and Vaux<Vdemag_low, then valley switching is disabled. The criteria at 806 are met and the state transitions to the not valley switching state 804. If the ringing amplitude is above the high threshold, then the controller remains in the valley switching state 802”, wherein examiner interpreted the comparison of ringing amplitude to a threshold, which indicates whether it is a new ringing cycle or not as including determining that the second peak value is less than first peak value, and in response repeating the execution of the tuning operation loop); and
responsive to the second peak value not being less than the first peak value, decrementing the transition time by the programmed amount (FIG. 8, Col. 15, Line 29-38 “FIG. 8 is a state machine diagram of a valley switching state and a not valley switching state with internal processes within each state. A controller transitions 806 from a valley switching state 802 to a not valley switching state 804 when a ringing amplitude measure, such as Vaux, falls below an amplitude threshold, such as Vdemag_high. Similarly, the controller transitions 808 from the not valley switching state 804 to the valley switching state 802 when a ringing amplitude measure, such as Vaux, rises below an amplitude threshold, such as Vdemag_high_hys”, [Abstract] “Adaptive enabling and disabling is described for valley switching in a power factor correction boost converter. In one example, a boost converter control system includes an amplitude detector to receive an amplitude signal from a boost converter that is related to ringing of the boost converter output. The amplitude detector determines the ringing amplitude. A valley switching controller compares the ringing amplitude to a first high amplitude threshold when valley switching is enabled and generates a valley switching disable signal if the ringing amplitude is below the first high amplitude threshold”, wherein examiner interpreted when ringing amplitude falls below a threshold as second peak value not being less than the first peak value, and wherein examiner interpreted valley switching as decrementing incremented rise time and fall time, and controlling power converter to switch according to the power converter control signal having a rise time and fall time).
BONDADE, and Twelkemeijer are analogous art because they are from the same field of endeavor and contain overlapping structural and functional similarities. They both relate to power converters.
Therefore, at the time of effective filing date, it would have been obvious to a person of ordinary skill in the art to modify the above method of determining peak value of voltage oscillations, as taught by BONDADE, and incorporating comparing peak voltage oscillation values, as taught by Twelkemeijer.
One of ordinary skill in the art would have been motivated to improve minimizing switching losses in the converter and improve overall efficiency, as suggested by Twelkemeijer (see Col. 1, Line 25-37).
Regarding claim 16, BONDADE, and Twelkemeijer teaches all of the features with respect to claim 15 as outlined above.
BONDADE further teaches wherein decrementing the transition time based on the determined value of voltage oscillations at the switch node reduces electromagnetic interference radiated by the power converter (Paragraph [0016] “At least some of the embodiments disclosed herein are directed to a ring amplitude sensor circuit which is configured to measure a peak AC amplitude of a ringing voltage and, in response to the measured peak AC amplitude, the ring amplitude sensor is configured to adjust a control signal driving a switch. Because the magnitude of the control signal impacts switching speed, and further because switching speed impacts switching loss, EMI noise and ringing, adjusting the control signal can adjust the switching speed of the switch, which, in turn, adjusts (e.g., reduce) the magnitude of the ringing. In some embodiments, as described further below, the magnitude of the ringing can also be adjusted by altering a start time of a ringing mitigation phase when the switch transitions between on/off states”, wherein examiner interpreted adjusting control signal based on peak amplitude of ringing to reduce EMI noise and switching losses as modifying the rise time and the fall time of the power converter control signal based on a measured peak value of voltage ringing at the switch node reducing electromagnetic interference radiated by the power converter).
Regarding claim 18, BONDADE, and Twelkemeijer teaches all of the features with respect to claim 15 as outlined above.
BONDADE further teaches wherein the programmed amount is less than the transition time (Paragraph [0036] “As discussed above in FIG. 1, there can be a transition from a very high voltage of 1000 V to ground when the low-side switch 140 is turned on and this transition isn't instantaneous and occurs with time. In some embodiments, the turn on time of the low- side switch 140 can be divided into three phases—negative dV/dt transition time T1 as phase 1, ring mitigation time T2 as phase 2 and complete turn on time T3 as phase 3. For example, the time T1 can be defined as the time taken by the low-side switch 140 during negative dV/dt transition. The time T2 can be the time during which high oscillation signal (ringing) is damped and the time T3 can be time when the low-side switch 140 is driven to be completely turned on”, wherein examiner interpreted turning on switch in phases to includes the programmed amount to be less than each of the rise time and fall time).
Allowable Subject Matter
Claims 5, 11, and 17 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.
Citation of Pertinent Prior Art
The prior art made of record and on the attached PTO Form 892 but not relied upon is considered pertinent to applicant's disclosure.
BALAKRISHNAN et al. [USPGPUB 2024/0030809] teaches a power converter includes a damping circuit.
Cohen [USPGPUB 2021/0013807] teaches methods, apparatus, systems and articles of manufacture are disclosed to reduce switching losses occurring in power converters.
PETO [WO 2019021186 A1] teaches a system for ensuring an oscillating voltage is maintained at optimum resonance.
Chen et al. [USPGPUB 2012/0068774] teaches an amplitude control circuit including a pair of peak detectors.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DHRUVKUMAR PATEL whose telephone number is (571)272-5814. The examiner can normally be reached 7:30 AM to 5:30 AM.
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, Mohammad Ali can be reached at (571)272-4105. 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.
/D.P./ Examiner, Art Unit 2119
/MOHAMMAD ALI/ Supervisory Patent Examiner, Art Unit 2119