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Exhibit A
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IN THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF DELAWARE POWER INTEGRATIONS, INC., a Delaware corporation, Plaintiff, v. FAIRCHILD SEMICONDUCTOR INTERNATIONAL, INC., a Delaware corporation, and FAIRCHILD SEMICONDUCTOR CORPORATION, a Delaware corporation, Defendants. C.A. No. 04-1371-JJF
REBUTTAL EXPERT REPORT OF ROBERT BLAUSCHILD
1.
I, Robert Blauschild, am being offered as an expert to testify on behalf of Plaintiff
Power Integrations, Inc. ("PI") in the above captioned matter. I have previously submitted a report regarding infringement of U.S. Patent Nos. 6,229,366 B1 (the '366 patent), 6,249,876 B1 (the '876 patent), and 6,107,851 (the '851 patent) by Defendants Fairchild Semiconductor Corporation and Fairchild Semiconductor International, Inc. ("Fairchild"). I submit this report in rebuttal to the report submitted by Dr. Paul Horowitz regarding PI's patents.
QUALIFICATIONS AND PROFESSIONAL EXPERIENCE 2. report. My qualifications and professional experience are set forth in my initial expert
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I.
INFORMATION CONSIDERED 3. In addition to the information cited in my initial expert report, I have reviewed
and considered the information specifically cited in this report including the following: a. Expert Report of Dr. Paul Horowitz. b. Exhibits to Dr. Horowitz's Expert Report. c. References cited in Dr. Horowitz's Expert Report. 4. For purposes of this report, I have assumed that all references cited by Dr.
Horowitz are prior art. Nevertheless, I offer no opinion as to whether these references are prior art under the patent statutes. 5. I have formed the opinions set forth in this document based on my review of the
information referenced above and on my experience. As I continue to work on this case, I may acquire additional information and/or supplemental insights that result in additional opinions. I note that Fairchild and Dr. Horowitz have modified in a number of respects the positions originally provided by Fairchild in its claim construction and non-infringement contentions. I have attempted to understand those differences and respond to what I understand to be Dr. Horowitz's and Fairchild's current arguments. I reserve the right to supplement my rebuttal report in light of continuing fact discovery, opinions from Fairchild's experts, and/or trial or deposition testimony. In addition, I reserve the right to provide rebuttal opinions and testimony in response to Fairchild's experts, and rebuttal testimony to Fairchild's fact witnesses. 6. I further reserve the right to use animations, enlargements of exhibits and/or
demonstratives, and other devices to illustrate my rebuttal opinions. II. SUMMARY OF REBUTTAL OPINIONS 7. I expect to testify that the asserted claims of the '366, '851 and '876 patents are
not anticipated by the prior art relied upon by Dr. Horowitz in his report. Specifically, I intend to 2
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testify that each of the prior art references cited by Dr. Horowitz is missing one or more of the limitations that are set forth in the asserted claims of the '366, '851 and '876 patents. I also intend to testify that the asserted claims of the '366, '851 and '876 patents would not have been obvious to one of ordinary skill in the art at the time of the invention. I further intend to testify that the asserted claims of the '366, '851 and '876 patents would be understood by those skilled in the art and are adequately disclosed in the respective specifications of the patents.
III.
35 U.S.C. § 102 AND § 103 UNDERSTANDINGS 8. It is my understanding, under 35 U.S.C. § 102, that to anticipate a claim means
that each individual reference must disclose every limitation of that claim of the patent, or the limitations must be inherent in the reference. In order for a limitation to be inherent in a reference, one of skill in the art would understand that the limitation must be present as a matter of technical necessity in the context of the reference, not that the limitation could or might be present, for example, as a choice of the designer. 9. I understand that a claim is invalid for obviousness under 35 U.S.C. § 103 if two
or more references in combination disclose, either expressly or inherently, or render obvious each and every limitation of the claim, and one of ordinary skill would have been motivated to combine the two or more references in a manner that would embody or teach the claimed invention. I further understand that there must be a demonstrated motivation to combine the references to arrive at the claimed invention and such motivation can not be found from a hindsight examination of the art in view of the claimed invention. I also understand that a claim can be obvious in light of a single prior art reference, but there must be a teaching, suggestion or motivation to modify the reference to achieve the claimed invention. I further understand that
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secondary considerations such as commercial success or long felt need, for example, should be considered if evidence of them is present and may provide objective indicia of non-obviousness.
IV.
THE REFERENCES RELIED UPON BY DR. HOROWITZ 10. In his report, Dr. Horowitz relies upon a number of references to support his
conclusions that the claims of Power Integrations' patents are anticipated or obvious. As detailed in my analyses of these references below, none of them alone anticipates or in any combination proposed by Dr. Horowitz renders obvious any of the asserted claims. 11. I have relied both on Dr. Horowitz's analysis and my own reading of the
references because, as discussed below, in many instances, Dr. Horowitz merely makes conclusory statements, without identifying claim elements in his references or giving reasons why he believes elements would be inherent or obvious. I reserve the right to respond if and when Dr. Horowitz adds such information to his opinions. 12. With respect to the '366 and '851 patents, Dr. Horowitz appears to argue that
anything that does any kind of soft start, or anything that varies frequency in any way-- regardless of purpose, method, or context--anticipates and/or renders obvious PI's circuit patents. This sort of argument trivializes the art of circuit design and bypasses the actual inventions -- the point of the inventions is an integrated soft start circuit that is regulation-loopindependent, and frequency variation that is cyclical during normal operation for EMI reduction, and none of the references discloses or teaches the claimed inventions (or the combination thereof found in some of dependent claims). 13. As pointed out below, circuitry for generalized soft start functionality and for
varying switching frequency were disclosed in several references cited in the prosecution of the PI patents. The fact that the PI patents issued illustrates the differences ignored by Dr. Horowitz. 4
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14.
Some of the asserted dependent claims require a monolithic solution to soft start
and/or frequency variation. To circuit designers and others in the semiconductor industry, "Monolithic" means made from a single crystal. This is consistent with the parties' currently agreed upon construction of "monolithic." All of the components are part of the single integrated circuit chip. See, e.g., http:/www.websters-onlinedictionary.com/definition/monolithic: "Pertains to the single silicon substrate in which an integrated circuit is constructed." Circuit designers strive to include as many of the components necessary for an application on the chip because that makes the product more attractive to a user (fewer extra components to buy and take up circuit board space). But sometimes components are intentionally left off of the chip because that adds flexibility to the product (e.g. the same chip could be used in different applications by choosing different external components). Sometimes components are left external because they are too difficult to integrate on the chip (e.g. large value capacitors that would greatly increase chip size and cost). 15. Dr. Horowitz takes the position that "monolithic" refers to circuits that are
integrated but also include components that are not on the chip. [Horowitz Report at ¶¶ 72-73.] He appears to reason that because a chip is monolithic, and may require external components in an application, that the combination of the chip and the external components is "monolithic." It is not. Following Dr. Horowitz's reasoning, if additional internal components were moved outside the integrated part of his "monolithic" circuit, then the combination would still be "monolithic." There is no way to draw a line as to how much of a circuit has to be in the integrated portion of Dr. Horowitz's "monolithic" circuit for the circuit to remain monolithic. Dr. Horowitz's position renders the term "monolithic" meaningless.
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16.
Dr. Horowitz also takes the position that "the reduction of a useful circuit to a
monolithic chip is not an `invention:' it is the logical next step." [Horowitz Report at ¶ 75.] This again trivializes the art of integrated circuit design. None of the integrated circuits cited by Dr. Horowitz or in the prosecution histories of the patents operates without any external components. Following Dr. Horowitz's logic, none of the designers of those chips was interested in the "size, cost, system complexity, and reliability" advantages Dr. Horowitz cites as the reason for providing a monolithic solution. As discussed above, sometimes it's preferred to NOT provide a monolithic solution, and in some cases it's just not practical (unless someone comes up with an invention to make it practica1!). 17. At the hearing in this matter, I may describe each of the references relied upon by
Dr. Horowitz. My trial testimony may also include animations, demonstratives, enlargements, and other devices to illustrate various aspects of the references cited by Dr. Horowitz.
V.
CLAIM CONSTRUCTION 18. I will address claim construction issues below as they come up in the discussion
of each reference, except for the terms "soft start circuit" and "frequency variation signal" which, because of their importance, I will address first here. Dr. Horowitz has applied these terms in a way very different than meant in the PI patents. This allows him to identify what he alleges is invalidating prior art that in many instances does not achieve the benefits of the inventions, is the same as art identified in the prosecution history of the patents, and is distinguished by the patents themselves as not being the inventions. 19. Soft start functionality existed before the '851 and '366 patents. The patents-in-
suit, however, describe a particularly advantageous way of implementing the soft start function. The common specification for these patents describes prior art that uses an external capacitor for 6
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soft start timing. ['366 patent at col. 2, line 65 col. 3, line 17.] The patents state: An object of an aspect of the present invention is directed to a pulse width modulated switch that has integrated soft start capabilities. ['366 patent at col. 4, lines 27-29.] In addition, each of the disclosed embodiments of a soft start circuit use a frequency variation signal to provide soft start timing. [e.g. Figures 3, 6, and 9 and signal 400.] The patents state: The frequency variation signal 400 is provided to soft start circuit 410. ['366 patent at col. 6, lines 49-50.] 20. The soft start circuitry disclosed in the `366/'851 patents operates separately from
the regulation loop, and can thus be used with different types of regulation without modification. For example, the same soft start circuit 410 can be used with voltage-mode regulation (as shown in Figures 3 and 6), or with current-mode regulation (not shown) or with fixed pulse width digital feedback regulation (as shown in Figure 9). The patents state: Either current or voltage mode regulation may be utilized by the present invention without departing from the spirit and scope of the present invention so long as a signal indicative of the power supplied to the load is supplied to the feedback terminal 825 of the regulation circuit 850. [e.g., `366 col. 11, lines 30 34.] 21. Dr. Horowitz, as detailed below, alleges that circuitry that includes an external
soft start capacitor can be used to invalidate claims of the '366 and '851 patents. [Horowitz Report at ¶ 66.] This position is at odds with the prosecution history. For example, the SG1526 has a soft start capability that uses an external capacitor and would meet all of the requirements of at least '366 claim 1 according to Dr. Horowitz's understanding of the claim. The SG1526 is shown in an Electronic Design article cited as prior art on the face of the '366 patent. [Power MOSFETs take the load off switching supply design.] U.S. Patent No. 4,890,210, cited as a prior art reference in the '366 and '851 prosecutions, shows a Unitrode 2524A chip used with
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external soft start components. This reference would also meet all the limitations of at least '366 claim 1 according to Dr. Horowitz's understanding of that claim. U.S. Patent No. 5,034,871, also a reference cited in the '366 and '851 prosecution histories, shows a PWM controller chip that uses external components (72 and 71 in Fig. 1) for implementing soft start functionality. 22. Besides rendering several of Dr. Horowitz's references merely cumulative, these
references cited in the prosecution of the '366 and '851 patents demonstrate that the Examiner did not consider the inventions to include soft start implemented with external circuit components. This is clearly demonstrated also by the fact that Figure 1 of the '366 and '851 patents, which uses external soft start capacitor 110, is labeled prior art and was distinguished by the inventors in the specification. ['366 patent at col. 2, line 65 col. 3, line 17.] The Examiner explicitly recognized this as well. ['366 prosecution history, Notice of Allowability at 2 ("Fig. 1 should be designated by a legend such as Prior Art--because only that which is old is illustrated.")] Dr. Horowitz incorrectly claims that Figure 1 is invalidating prior art for '366 Claim 1. [Horowitz Report at ¶ 69.] 23. Dr. Horowitz surmises that the Examiner allowed the claims over Figure 1 of the
'366 and '851 patents because the figure allegedly does not show a maximum duty cycle signal. [Horowitz Report at ¶ 70 and ¶ 98.] Dr. Horowitz acknowledges, however, that the SMP211, which is shown and identified by part number in Figure 1, includes the maximum duty cycle signal as shown in its datasheet. Thus, according to Dr. Horowitz's report, this claim element was missing when the Examiner looked at the application in the prosecution process, but present when Dr. Horowitz did his invalidity analysis. Presumably the Examiner knew of the SMP211 or would have looked at its datasheet.
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24.
The '366 and '851 Figure 1 circuit does not achieve the stated goal of these
patents with respect to soft start functionality integrated, independent, soft start capability. 25. I understand that Fairchild has taken the position that the soft start circuit should
be construed to be "a circuit that minimizes inrush currents at start up." This not only allows Dr. Horowitz to bypass the intent of the '366 and '851 patents with respect to soft start, but also sweeps in other soft start implementations clearly outside the scope of the '366 and '851 patents. For example, those of skill in the art knew that external filters or resistors could be used to limit inrush current. One example is shown in European Patent Application EP0748035A1, which includes an external resistor (R1 in Fig. 3) used to limit inrush current in a power conversion system. This reference was also cited in the prosecution of the '366 and '851 patents. Another reference cited in the '366 and '851 prosecution history, U.S. patent No. 5,041,946 (the "'946 patent"), shows a current source charging a capacitor to provide soft start functionality. [See, e.g., '946 patent items 31 and 32 in Fig. 2.] 26. The large number of different circuit arrangements that could be used for
providing soft start functionality cited in the prosecution histories and known to those of skill in the art at the time of the '366 and '851 inventions leads me to conclude that the term "soft start circuit" should be construed to be limited to the corresponding soft start circuit structures disclosed in the '366 and '851 specification, and their equivalents. As discussed in my opening report, the disclosed structures are latch 450, comparator 460 with oscillator ramp and frequency variation signal inputs, AND gate 455, and OR gate 425 shown in Figures 3, 6, and 9. [See, for example, `851 col. 5, line 66 col. 6, line 9; col. 6, line 25 col. 7, line 8; col. 11, line 64 col. 12, line 2.] The specification expressly excludes from the definition of "soft start circuit"
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circuits using an external soft start capacitor. [See, e.g., '366 patent at col. 4, lines 46-47 and capacitor 110 in Fig. 1.] 27. I understand that the parties have a dispute with respect to the term "frequency
variation signal." Fairchild's position that a frequency variation signal is a signal "used to modulate or change the frequency at which the switch is operated" bears no resemblance to what the frequency variation described and claimed in the '366 and '851 patents is about. 28. As described in my opening report and the '366/'851 specification, switching
regulators generate noise at the frequency at which they switch (Electromagnetic Interference or EMI). [e.g., '366 col. 1, lines 30-48.] By providing and responding to a signal that varies switching frequency cyclically over time, emitted interference is spread out over a range of frequencies around a nominal frequency so that the interference is not concentrated at one particular frequency, but spread out at a lower level at frequencies within the range of variation. [e.g., '366 patent at col. 3, lines 53-58; col. 6, lines 35-48; col. 9, lines 27-45.] The frequency variation described in the '366 and '851 patents is used to avoid a constant switching frequency during steady state operation of a switching voltage regulator. ['366 col. 8, line 56 col. 9, line 45.] 29. By constructing "frequency variation signal" as any signal that modulates or
changes the frequency at which the switch operates, Fairchild and Dr. Horowitz are able to render the frequency variation aspect of the '366 and '851 patents meaningless. For example, according to Fairchild's proposed construction, an external resistor or capacitor that is used to set the magnitude of a fixed operating frequency could be considered a "frequency variation circuit" that generates a "frequency variation signal" because two users can operate at different switching frequencies. As detailed below, Dr. Horowitz identifies such a circuit as invalidating prior art.
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[e.g., the Keller SMP260 article discussed below.] This is clearly incorrect. In such a scenario, each user operates with a single switching frequency, generates EMI at that frequency, and derives none of the benefit associated with the frequency variation described and claimed in the '366 and '851 patents. 30. According to Fairchild's construction and Dr. Horowitz's application of the term
"frequency variation signal," the Electronic Design article, cited in the '366 and '851 prosecution histories, would have all the elements of at least '851 claim 1, including a "frequency variation circuit" and "frequency variation signal" according to Dr. Horowitz's analysis (see, for example, Dr. Horowitz's analyses of the TEA2260 and TEA2262 first embodiments and the Keller reference). The Electronic Design article cited in the prosecution of the '366 and '851 patents demonstrates that the Examiner did not consider the frequency variation aspect of the inventions to be merely providing the capability to operate at different frequencies with a different choice of components. 31. Other deficiencies in the Fairchild proposed construction of "frequency variation
signal" will be detailed below with respect to Dr. Horowitz's application of that term to certain of his alleged invalidating references. 32. I believe that one of skill in the art would understand the "frequency variation
circuit" to be a circuit that provides the "frequency variation signal," and that the "frequency variation signal" is an internal signal that cyclically varies in magnitude during a fixed period of time and is used to modulate the frequency of the oscillation signal within a predetermined frequency range. This is how the "frequency variation signal" is described in the `366/'851 specification. [e.g., '366 patent at col. 6, lines 35 48; col. 7, lines 19 63; col. 7, line 54 col. 8, line 37; and col. 8, lines 52 55.] The "cyclical" and "predetermined" nature of the frequency
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variation signal are important because they allow EMI reduction and avoid the problem of line and load sensitivity discussed in the patents. [e.g., `851 col. 4, lines 36 38; col. 3, lines 31 37; col. 7, lines 45 49;col. 6, lines 10 -17.]
VI.
REBUTTAL OPINIONS FOR THE '366 PATENT A. 33. Conclusions Regarding the '366 Patent At the hearing in this matter, I expect to testify that claims 1, 2, 8, 9, 10, 14, 16,
and 18 of the '366 patent are not anticipated or rendered obvious by the references cited by Dr. Horowitz. At the hearing, I intend to point out that each of the references cited by Dr. Horowitz lacks limitations required by the asserted claims of the '366 patent. I may also testify about the context of the '366 invention and the technology preceding and following the '366 invention including its differences from the claimed invention. B. The Validity of the '366 Patent 1. 34. General Response to Dr. Horowitz's Report re the '366 Patent
Dr. Horowitz discusses the PI '366 patent in paragraphs 60-93 of his report and
makes several conclusory assertions that the '366 patent is anticipated or rendered obvious in this section. Although I discuss in greater detail below the specific reasons I disagree with Dr. Horowitz's conclusions regarding various references for which he has provided claim charts, I also note the following additional problems in the text of Dr. Horowitz's Report. 35. In paragraph 66, Dr. Horowitz provides a large list of allegedly anticipatory
references, but Dr. Horowitz's assertion that these references anticipate the '366 patent is conclusory. Dr. Horowitz has provided no reason, and certainly not clear and convincing evidence, that any of these references is in fact anticipatory. I disagree with Dr. Horowitz's conclusory allegation in paragraph 66. 12
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36.
I also disagree with Dr. Horowitz's argument in paragraph 67 regarding the
TEA2260. As discussed below, the TEA2260 relies on an external capacitor to implement soft start and is, therefore, like the distinguished prior art, not an equivalent structure to the soft start circuit of the claims. 37. I also disagree with the conclusion in Dr. Horowitz's report at paragraph 68. Dr.
Horowitz makes a blanket statement that differences between soft start circuit box 410 in the patent's Figures 3, 6, and 9 circuits and prior-art circuits would have been obvious. This makes no sense to me without first pointing to any differences and then doing an analysis. The one theory that Dr. Horowitz proposes the prior art circuits already have a DMAX signal, thus ANDing it with another DMAX signal that grows with time would have suggested itself does not make sense to me. If a circuit already has a DMAX signal, why add another one? That would be non-obvious. 38. In paragraph 69, Dr. Horowitz suggests that `366/'851 Figure 1 has the soft start
circuit of `366 claim 1. I disagree. As discussed below, the patent itself distinguishes the claimed soft start circuit from the soft start functionality of Figure 1. 2. Detailed Response to Dr. Horowitz's Claim Charts for the '366 Patent a. 39. SMP211 + Figure 1 of '366 patent
This combination is missing the soft start circuit of independent claims 1 and 9
and therefore dependent claims 2, 8, 10, 14, 16, and 18. 40. While the patent states that the circuit of Figure 1 has soft start functionality, the
patent also distinguishes it a being a prior art circuit that uses an external soft start capacitor. In addition, the patent distinguishes this prior art circuit as having problems with initial cycles. The patent describes the claimed soft start circuitry that solves the initial cycle problem. [`366 col. 3, lines 2 17; col. 6, line 49 col. 7, line 6.] An implementation of soft start using an external 13
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capacitor is not the same as the structure corresponding to the claimed "soft start circuit" or its equivalent. Claim 2 & 16 41. The asserted combination is missing the monolithic soft start circuit component of
dependent claims 2 and 16. I disagree with Dr. Horowitz's position that it would be inherent or obvious to combine the soft start circuit he points to in a monolithic solution. 42. My understanding of "inherent" with respect to patent claims is that an element
not shown must be there as a matter of necessity, not that it could be there as a matter of design choice. The fact that Figure 1 exists as it is shows that it is not necessary to do soft start functionality monolithically. "Inherency," as I understand it, is not removing an existing circuit for performing a function, and replacing it with a different circuit for performing that function (and in particular using a replacement that meets specific claim language). Such a substitution would merely be hindsight redesign based on the patent. 43. Dr. Horowitz does not identify what he believes to be the soft start circuit in
Figure 1, but does opine that it includes capacitor 110. It would not be obvious to move external capacitor 110 into the SMP211 chip. First, as discussed above, a designer just can't take anything outside a chip and move it onto a chip. There is no value given for capacitor 110, and no basis to determine that it is even practical to integrate such a component. In addition, capacitor 110 is on the secondary side of the regulator, isolated from the SMP211. First, it would not make sense to move that component across the isolation barrier between the primary and secondary side of the regulator. And second, it is not obvious how such a move would provide any soft start capability, because the capacitor, as it is placed, works with secondary side
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components to do soft start. Dr. Horowitz provides no description of how he would modify the combination. 44. If such a modification was obvious, why are there so many devices that use
external soft start capacitors (both before and after the invention)? In addition, the Examiner had the disclosure showing Figure 1 with its external soft start capacitor in front of him and allowed the claims. 45. By stating that "it is inherent or obvious," Dr. Horowitz admits that the
monolithic element described in Claims 2 and 16 is not shown. His opinion that it could be added is based on hindsight, and even so is incorrect as described above. 46. The combination is also missing the frequency variation circuit and signal of
claim 14. Dr. Horowitz points to resistor 140 as being a frequency variation circuit that produces a frequency variation signal (current 135 through that resistor). This is not correct. 47. Current 135 is not an internal signal that cyclically varies in magnitude during a
fixed period of time and is used to modulate the frequency of the oscillation signal within a predetermined frequency range. The patent does not call current 135 a frequency variation signal. In fact, the patent distinguishes this signal from the invention because it is NOT internal or predetermined. [e.g., col. 3, lines 40 46.] The patent states, describing the invention: That is, the switching frequency of the pulse width modulated switch 262 varies according to an internal frequency variation signal. This has an advantage over the frequency jitter operation of Fig. 1 in that the frequency range of the presently preferred pulse width modulated switch 262 is known and fixed, and is not subject to the line voltage or load magnitude variations. [col. 6, lines 20 26.]
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b. 48.
UC1828/2828/3828; Unitrode App. Note U-128
The UC1828 is missing the soft start circuit of independent claims 1 and 9 and
therefore dependent claims 2, 8, 10, 14, 16, and 18. 49. These references teach conventional soft start whereby the control loop signal
(feedback) is modified to limit duty cycle rather than using an independent soft start circuit as disclosed in the `366 patent. In addition, these references show an external soft start capacitor used to clamp the output of an error amplifier. This is precisely what is shown in the Electronic Design article cited in the '366 prosecution history and described above. The Examiner had the Electronic Design article in front of him and allowed the claims. 50. With respect to dependent claims 2 and 16, once again Dr. Horowitz opines that
"it is inherent or obvious" to combine all of the regulation circuitry into a single monolithic device." I disagree for the reasons discussed above. 51. This reference in particular shows that it is not straightforward to move external
components into a chip. The external soft start capacitor value is shown as 2.2nF. [FSC1686718.] Those of skill in the art know that a 100pF capacitor is large for an integrated circuit capacitor. A 2.2nF capacitor is 22 times larger and would take up so much area to integrate that the die size of the modified UC1823 product would be greatly enlarged, resulting in greatly increased cost. The `366 patent avoids this by having integrated soft start capability. 52. The UC1823 is also missing the monolithic switch and first terminal of claims 2
and 16. Integrating the switch and first terminal would require a redesign of the fabrication process by which the UC1823 is built, and a massively larger die size and cost. Such an undertaking would be impractical and non-obvious. 53. Because of the difficulties described above with respect to integration, this
reference teaches away from the '366 claims. 16
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54.
This reference does not have the frequency variation circuit or frequency variation
signal of claim 14. Dr. Horowitz does not claim that it is shown. Instead, Dr. Horowitz opines again that it would be inherent or obvious, without any support. The fact that this and numerous circuits have soft start functionality without frequency variation circuits (both before and after the invention) show that it is not inherent. The only motivation to add frequency variation circuitry, and additionally have it interact in a particular way with soft start circuitry, is hindsight to fill in a hole in Dr. Horowitz's claim chart. c. 55. TEA2260 + AN376
These references are missing the soft start circuit of independent claims 1 and 9
and therefore dependent claims 2, 8, 10, 14, 16, and 18. 56. The TEA2260 uses an external soft start capacitor with specified range of 47nF to
1uF [FCS1687339], and cannot be the claimed soft start circuit as discussed above. 57. Dr. Horowitz's contention that the TEA2260 has a monolithic soft start circuit as
required by claims 2 and 16 is not correct. These references clearly show the use of an external soft start capacitor. [e.g., FCS1687375.] 58. In addition, Dr. Horowitz does not identify the maximum duty cycle signal
produced by an oscillator as required by claims 1, 2, 8, and 10. None is shown in these references. AN376 does show a maximum duty cycle signal, but it is generated by an auxiliary PWM circuit. [FCS1687356.] 59. The TEA2260 does not have the frequency variation circuit or frequency variation
signal of claim 14. AN376 shows an external transistor used to switch operating frequency during power supply start up. Such operation is specifically distinguished in the `366 patent from the frequency variation described in the patent as discussed above. In normal operation, the TEA2260 operates with a fixed switching frequency, and generates EMI at that fixed frequency, 17
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exhibiting the problem the '366 patent addresses and solves. Even considering start up, frequency is never varied as described in the '366 patent. There's one fixed frequency during startup, and another fixed frequency during normal operation. This is nothing like the cycling of switching frequency to minimize EMI during normal operation as described in the '366 patent. d. 60. Goodenough + SMP3
The Goodenough article describes a delay in turning on, not a soft start. And
there is only a brief mention at that -- there is no discussion of how anything other than a delay in startup might be done. All the article says is that there is soft start with an internal capacitor connected to an intermediate stage of the error amplifier. It does not teach an enabling disclosure of the claimed soft start circuit. Just having a capacitor which provides a delay inside doesn't limit inrush currents or prevent overshoot during startup. 61. At best, this reference teaches essentially the conventional soft start in which the
feedback signal is clamped. But even that is not truly the case. 62. I disagree with Dr. Horowitz's explanation of how the circuit on page 14 of the
SMP3 schematic diagrams works. Dr. Horowitz states: As the voltage on the node SFT_STR rises, the voltage on VOUT also rises. This is not correct. As the voltage on the capacitor on the test pad ramps up, VOUT will remain clamped low and duty cycle will be minimum or zero. Nothing will happen until the capacitor charges to approximately 1.25V, after which time VOUT will be controlled by the input VIN-. This agrees with how the Goodenough article describes the circuit operation: Until the capacitor is fully charged, the error amplifier output is clamped low, limiting the duty cycle and peak current of the switch during startup. [FCS0528088.] Thus the circuitry pointed to by Dr. Horowitz is merely a delay circuit, and does not provide soft start functionality.
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63.
Internal soft start functionality (or soft start functionality of any kind) was not
described or shown in the data sheet for SMP3, and the SMP3 schematic diagrams show that what is described in the article would not have worked to provide soft start. The claimed internal soft start simply wasn't in the SMP3. 64. The Goodenough and SMP3 references are missing the soft start circuit of
independent claims 1 and 9 and therefore dependent claims 2, 8, 10, 14, 16, and 18. 65. The article's disclosure is not sufficient to enable the function and the product
itself did not have it. Dr. Horowitz ignores the lack of any soft start feature in the datasheet. The "analysis" of the SMP3 schematics is directly contrary to how the inventor explained the circuit when questioned about the schematics, and contrary to the description provided in the article itself. According to the inventor, the internal capacitor shown and the fact that the intermediate stage of the high-gain error amplifier only has one threshold show that the pieces Dr. Horowitz points to cannot perform a soft start function. Even if the SMP3 could perform a soft start function, or the disclosure of the article were enough to be enabling, the disclosure would be the same as the U-133 reference (see below), and would not be an equivalent structure because it would simply act to limit the error-amplifier output in the feedback loop as with "conventional" soft start. 66. These references do not have the frequency variation circuit or frequency
variation signal of claim 14. Dr. Horowitz does not claim that they are shown in these references. Instead, Dr. Horowitz opines again that it would be inherent or obvious, without any support. This is pure hindsight to fit the claim limitation, and, as explained above with similar arguments, fails to come close to establishing obviousness of the claim.
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e. 67.
Stasi + LM2577 + LM2588
These references are missing the soft start circuit of independent claims 1 and 9
and therefore dependent claims 2, 8, 10, 14, 16, and 18. 68. The soft start implementation of these references is not the same as the
corresponding structure or equivalent. These references use an external capacitor, different and not equivalent to disclosed structure (distinguished from the invention as described above). This is the same as the Electronic Design article and several other references discussed above, which were before the Examiner when he allowed the claims. These references also use a switching circuit in combination with an external compensation capacitor, and do not compare a frequency variation signal to an oscillator ramp signal. 69. Dr. Horowitz does not identify any maximum duty cycle signal provided by an
oscillator, and the references don't show this element of claims 1, 2, 8, and 10. The output from the oscillator is referred to as a "reset pulse." This is inconsistent with the concept of a maximum duty cycle signal. 70. For claims 2 and 16, Dr. Horowitz relies on a statement that The soft-start feature
of our new regulator is unique in that it does not require any additional external components. This does not state that there are no external components in the soft start circuit. The circuit uses an external compensation capacitor to provide soft start functionality. If that external capacitor were not used, there would be no soft start feature. 71. Dr. Horowitz claims that it is inherent or obvious that the LM2577 could be used
in an AC mains flyback application as required by claims 8 and 18. I disagree. Dr. Horowitz relies on the circuit of Figure 15 of the LM2577 datasheet, which shows a flyback application. The absolute maximum allowed supply voltage and switch voltage for the LM2577 are 45V and 65V, respectively. [FCS0524994.] The LM2577 would be destroyed if it were used in an AC 20
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mains application, for example, 85 265V as described in the patents. [`366 col. 10, lines 9 14.] 72. These references do not have the frequency variation circuit or frequency
variation signal required by claim 14. Dr. Horowitz does not identify any frequency variation circuit or signal. If Dr. Horowitz meant to identify the circuitry that changes the operating frequency during an output short circuit condition, then that would not be the claimed frequency variation circuit and signal. There is no EMI improvement, because the part is always operating at a fixed frequency. In addition, the change to a lower fixed frequency during an output short circuit condition is driven by the output load, not any internal frequency variation signal generated by a frequency variation circuit. The patent specifically distinguishes such a load dependent change from the invention. ['366 patent at col. 3, lines 40 46.] 73. If Dr. Horowitz meant to identify the externally applied on/off signal, then that
would be incorrect also. Such a signal would not be generated by a frequency variation circuit (internal or external), and would not result in any EMI improvement. 74. The oscillator shown in these references operates at a fixed frequency during
normal operation and at a lower fixed frequency if the feedback indicates a short circuit or the part is powered down. This can't possibly do anything to solve the EMI problem, which is the purpose of the invention. f. 75. '995 patent + AN-918 + LM3001/3101
These references are missing the soft start circuit of independent claims 1 and 9
and therefore dependent claims 2, 8, 10, 14, 16, and 18. 76. The LM3001 and LM3101 and the `995 circuit all have external capacitors that
operate to effect the feedback loop as with other conventional soft start features.
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77.
These references are no different in this regard than prior art (such as the
Electronic Design article) that were before the Examiner when he allowed the claims. 78. Dr. Horowitz once again relies on his "inherent or obvious" argument for why
claim 2 is invalid based on these references. These references describe circuits with large external capacitors. His reasoning is incorrect for the reasons described above. 79. The LM3001 does not have the frequency variation signal of claim 14 of the
patent; it operates with a lower frequency only during an output short circuit. This is not the frequency variation circuit and signal of the `366 patent. See the discussion above with respect to the Stasi circuit. In addition, the LM3001 uses external resistors as part of it's short circuit frequency shift circuit, unlike the internal frequency variation circuit disclosed in the `366 patent. 80. The LM3001 doesn't have any frequency variation signal, and Dr. Horowitz
doesn't say that it does. 81. Although Dr. Horowitz lists the '995 patent in the title of his claim chart, he does
not refer to that patent in the body of his chart. The '995 circuit has an external soft start capacitor and a short-circuit frequency shift circuit like the LM3101, and shares the same deficiencies with respect to the '366 claims. g. 82. Keller Article + SMP240/260 datasheet (but no cites to datasheet in claim chart)
These references are missing the soft start circuit of independent claims 1 and 9
and therefore dependent claims 2, 8, 10, 14, 16, and 18. 83. The structure in these references is not the same as the corresponding structure or
equivalent because the reference teaches "conventional" soft start whereby a control loop signal (feedback) is modified to limit duty cycle rather than using an independent circuit. An internal digital current source acts in summing junction of feedback circuit to provide soft start 22
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functionality. Dr. Horowitz does not identify any signal instructing the drive circuit to disable the drive signal during at least a portion of the on-state of the maximum duty cycle. 84. There is no maximum duty cycle signal shown provided by an oscillator as
required by claims 1, 2, 8, and 10. Dr. Horowitz does not identify any, but instead just repeats the claim language, saying this reference has it. It doesn't. 85. With respect to claims 2 and 16, Dr. Horowitz claims that Figures 1 and 11 of the
Keller paper show a monolithic oscillator. This is not correct. An external capacitor is shown in each of these figures (labeled C( in Figure 11). 86. With respect to claim 14, Dr. Horowitz relies on the fact that the SMP240/260
uses an external timing capacitor to set its fixed switching frequency to satisfy the frequency variation claim requirement. I disagree. Once a user picks a capacitor in an application, operating frequency is fixed. There is no frequency variation. This is no different than other fixed frequency references before the Examiner. Based on Dr. Horowitz's reasoning, any oscillator would include a frequency variation circuit and signal because the oscillator frequency could be changed by changing component values. This is a good example of why Fairchild's claim construction of frequency variation signal can't be correct. 87. Dr. Horowitz alternately proposes that it would be obvious to add a frequency
variation circuit. This is pure hindsight to fit the claim limitation, in effect saying that it doesn't have this but it could. The fact that this and numerous circuits have soft start functionality without frequency variation circuits (both before and after the invention) shows that it would not be obvious that it should be added. The only motivation to add frequency variation circuitry, and additionally have it interact in a particular way with soft start circuitry, is hindsight to fill in a hole Dr. Horowitz's claim chart.
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h. 88.
UCC3800 series & Unitrode App. Note U-133
These references are missing the soft start circuit of independent claims 1 and 9
and therefore dependent claims 2, 8, 10, 14, 16, and 18. 89. The soft start circuitry of these references is not the same as the corresponding
structure or equivalent. The structure in these references is not the same as the corresponding structure or equivalent because the reference teaches "conventional" soft start whereby a control loop signal (feedback) is modified to limit duty cycle rather than using an independent circuit. These references do not compare a frequency variation signal to an oscillator ramp signal. An internal capacitor is used to clamp error amplifier output voltage. As discussed above, the soft start circuit of the patent operates in a different way. Because it is independent of the feedback loop, the patented soft start circuit can be used with any type of PWM control. The conventional soft start circuit, which clamps error voltage, cannot. 90. With respect to claims 2 and 16, Dr. Horowitz relies on Figure 27 and describes
the switch as being monolithic. Figure 27 of the U-133 Application Note shows external oscillator components, so this reference is not monolithic. 91. With respect to claim 14, these references do not have a frequency variation
circuit or signal, and Dr. Horowitz does not contend that they do. VII. REBUTTAL OPINIONS FOR THE '851 PATENT A. 92. Conclusions Regarding the '851 Patent At the hearing in this matter, I expect to testify that claims 1, 2, 4, 7, 9, 10, 11, 13,
16, and 17 of the '851 patent are not anticipated or rendered obvious by the references cited by Dr. Horowitz. At the hearing, I intend to point out that each of the references cited by Dr. Horowitz lacks limitations required by the asserted claims of the '851 patent. I may also testify
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about the context of the '851 invention and the technology preceding and following the '851 invention including its differences from the claimed invention. B. The Validity of the '851 Patent 1. 93. General Response to Dr. Horowitz's Report regarding the '851 Patent
In general, as discussed below, Dr. Horowitz relies on references that describe
fixed frequency operation, the very operation that the '851 patent is designed to avoid. These references do not vary frequency over a range as claimed, or achieve the benefit of EMI reduction, thus providing further evidence that Fairchild's construction of "frequency variation signal" can't be correct. 94. In addition, Dr. Horowitz relies on references that have external signals used to
alter operating frequency. The '851 patent clearly distinguishes such signals from the invention. Dr. Horowitz identifies an external signal in the '851 Figure 1 circuit as the claimed frequency variation signal. The patent says otherwise: Alternatively, or in addition to soft start functionality, pulse width modulated switch 262 may also have frequency jitter functionality. That is, the switching frequency of the pulse width modulated switch 262 varies according to an internal frequency variation signal. This has an advantage over the frequency jitter operation of FIG. 1 in that the frequency range of the presently preferred pulse width modulated switch 262 is known and fixed, and is not subject to the line voltage or load magnitude variations. [col. 6, lines 10 17, emphasis added.] and Alternatively, or in addition to soft start functionality, pulse width modulated switch 262 may also have frequency jitter functionality. That is, the switching frequency of the pulse width modulated switch 262 varies according to an internal frequency variation signal. This has an advantage over the frequency jitter operation of FIG. 1 in that the frequency range of the presently preferred pulse width modulated switch 262 is known and fixed, and is not subject to the line voltage or load magnitude variations. [col. 11, lines 43 50, 25
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emphasis added.] The patent also states: Another object of an aspect of the present invention is directed toward a pulse width modulated switch that has integrated frequency variation capabilities. [col. 4, lines 21 23, emphasis added.] 95. Dr. Horowitz again in paragraphs 98 and 106 suggests that that the Dmax
oscillator output is the only difference between the '851 patent claim 1 and Fig. 1 of the '851 patent. As I noted above in the discussion of the '366 patent, Dr. Horowitz is incorrect. The Examiner noticed that Figure 1 did not appear to disclose an oscillator for generating a maximum duty cycle signal and a signal with a frequency range dependent on a frequency variation signal as recited in claim 1. [Page 5 of the December 13, 1999 Office Action.] As such the Examiner recognized the frequency variation signal, the frequency variation circuit that generated it, and their effect on the oscillation frequency were not disclosed in the prior art of record, including Figure 1. 96. In paragraph 107, Dr. Horowitz again sets forth a definition of "monolithic" that
includes external components. I disagree with his characterization as discussed above. 2. Detailed Response to Dr. Horowitz's Claim Charts regarding the '851 patent a. 97. '851 Pat Fig 1 + SMP211
The Figure 1 circuit and the SMP211 are missing the frequency variation circuit
and frequency variation signal of claims 1, 2, 4, 7, 9, 10, 11, 13, 16, and 17. They are also missing the oscillator with a frequency range that varies according to the frequency variation signal of these same claims. This is consistent with what the Examiner said when he allowed claims during the `851 prosecution. [Dec. 13, 1999 Office Action cited above.] Accordingly, Dr. Horowitz's suggestion that the claims were only allowed because they do not teach a maximum duty cycle signal [101] is incorrect.
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98.
The "frequency variation signal" identified by Dr. Horowitz is not internal (and,
as discussed above, specifically distinguished from the invention by the specification). The "frequency variation signal" identified by Dr. Horowitz is not predetermined. The specification also distinguishes this signal from the invention on this basis: Alternatively, or in addition to soft start functionality, pulse width modulated switch 262 may also have frequency jitter functionality. That is, the switching frequency of the pulse width modulated switch 262 varies according to an internal frequency variation signal. This has an advantage over the frequency jitter operation of FIG. 1 in that the frequency range of the presently preferred pulse width modulated switch 262 is known and fixed, and is not subject to the line voltage or load magnitude variations. [col. 6, lines 10 18, emphasis added.] 99. According to Dr. Horowitz, someone could build the Figure 1 circuit and infringe
the patent, even though the patent itself describes the circuit as prior art and the Examiner expressly said it was prior art. ['366 prosecution history, Notice of Allowability at 2 ("Fig. 1 should be designated by a legend such as Prior Art--because only that which is old is illustrated.")] This makes no sense to me. 100. Dr. Horowitz describes the voltage bias out of the SMP211 bias block as an
alternate frequency variation signal. Such a signal would not be produced by the claimed frequency variation circuit and would not be the claimed frequency variation signal. It would be produced by external circuitry and would not be predetermined. It would suffer from the same deficiency described in the patent. 101. With respect to claims 2 and 16, Dr. Horowitz once again resorts to his inherent
or obvious argument. Inherency is clearly incorrect. The Figure 1 circuit operates as it is, showing that there is no necessity to move resistor 140 into the chip. And to do so would not be
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obvious. Just the opposite. The fabrication process for the SMP211 would have to be modified to accommodate a resistor that could withstand hundreds of volts, and then inclusion of such a resistor would require the addition of another package pin, thereby raising the cost of the product. Dr. Horowitz provides no reason why it would be obvious to move the resistor inside the chip. 102. Dr. Horowitz's claim that "it is inherent or obvious that the frequency variation
signal could also be used as a soft start signal" as required by claims 4 and 13 is amazing. The figure 1 circuit does not connect its soft start operation (with external soft start capacitor 110 on the secondary side of the regulator) with resistor 140 on the primary side of the regulator, and thus inherency is clearly incorrect. And it would be obvious to avoid such interaction. These features are done separately, on separate sides of an isolation barrier, and there's no suggestion (other than from the '851 patent) to use a frequency variation signal as a soft start signal. 103. Dr. Horowitz provides no discussion of how his proposed redesign would be
done. His opinion is pure hindsight to fill in holes in his claim chart. 104. In addition, for reasons discussed above, the Figure 1 circuit does not have the
soft start circuit of this claim. b. 105. TEA2260 + AN376
These references are missing the frequency variation circuit and frequency
variation signal of claims 1, 2, 4, 7, 9, 10, 11, 13, 16, and 17. They are also missing the oscillator with a frequency that varies over a frequency range according to the frequency variation signal of these same claims. 106. The "frequency variation signal" identified by Dr. Horowitz is not internal.
Instead, it is at a pin of the integrated circuit.
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107.
The TEA2260 does not have the frequency variation circuit or frequency variation
signal of claim 1. AN376 shows an external transistor used to switch operating frequency during power supply start up. Such operation is specifically distinguished in the `851 patent from the frequency variation described in the patent as discussed above. In normal operation, the TEA2260 operates with a fixed switching frequency, and generates EMI at that fixed frequency, exhibiting the problem the '851 patent addresses and solves. Even considering start up, frequency is never varied as described in the '851 patent. With the TEA2260, there is one fixed frequency during startup, and another fixed frequency during normal operation. This disclosure is nothing like the cycling of switching frequency to minimize EMI during normal operation as described in the '851 patent. This TEA2260 circuit operates at ¼ frequency during startup and then it runs at full frequency, and it cannot possibly do anything to solve the EMI problem, the very purpose of the invention of the '851 patent. 108. In addition, Dr. Horowitz does not identify the maximum duty cycle signal
produced by an oscillator as required by claims 1, 2, 4, 7, 9, 10, 11, 13, 16, and 17. None is shown in these references. AN376 does show a maximum duty cycle signal, but it is generated by an auxiliary PWM circuit, not an oscillator [FCS1687356.] 109. With respect to claims 2 and 16, Dr. Horowitz again resorts to his "inherent or
obvious" argument. Neither is correct. The "frequency variation circuit" identified by Dr. Horowitz does not need to be incorporated on the chip it isn't as described -- and therefore there is no inherency. It would not be obvious that the circuitry pointed to by Dr. Horowitz could be integrated on the chip, particularly the 27nF capacitor, which one of skill in the art would have known would be impractical to integrate as discussed above. Thus the reference teaches away from claims 2 and 16.
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110.
Dr. Horowitz opines that it would be obvious to incorporate his "frequency
variation circuit" onto the TEA2260/61 chip because that is what is done in a subsequent device, the TEA2262. I disagree. Dr. Horowitz himself identifies external frequency variation circuitry in his analysis of the TEA2262 (see below). None of the TEA2260/61/62 parts have the claimed frequency variation circuit, and each has external components identified by Dr. Horowitz as being part of his "frequency variation circuit." 111. With respect to claims 4 and 13, the TEA2260 uses an external soft start capacitor
with specified range of 47nF to 1uF [FCS1687339.], and therefore doesn't have the claimed soft start circuit as described above. Dr. Horowitz does not claim that the claimed soft start circuit is shown. Instead he resorts to his "inherent or obvious" argument, stating that the "frequency variation signal could also be used as a soft start signal." Dr. Horowitz provides no discussion of how his proposed redesign would be done. His opinion is pure hindsight to fill in holes in his claim chart. c. 112. De Stasi article + LM2588
These references are missing the frequency variation circuit and frequency
variation signal of claims 1, 2, 4, 7, 9, 10, 11, 13, 16, and 17 of the '851 patent. They are also missing the oscillator with a frequency that varies over a frequency range according to the frequency variation signal of these same claims. 113. Dr. Horowitz does not identify any maximum duty cycle signal provided by an
oscillator, and the references don't show this element of claims 1, 2, 4, 7, 9, 10, 11, 13, 16, and 17. The output from the oscillator is referred to as a "reset pulse." This is inconsistent with the concept of a maximum duty cycle signal. 114. These references are missing the drive circuit of claims 1, 2, 4, 7, 9, and 10. The
magnitude of the oscillation signal (which, as described above, is not the oscillation signal of 30
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these claims) is not compared to a variable threshold. Dr. Horowitz does not identify any drive circuitry in these references, and merely recites the claim language for his analysis. 115. Dr. Horowitz does not identify any frequency variation circuit or signal. If Dr.
Horowitz meant to identify the circuitry that changes the operating frequency during an output short circuit condition, then that would not be the claimed frequency variation circuit and signal. There is no EMI improvement, because the part is always operating at a fixed frequency. In addition, the change to a lower fixed frequency during an output short circuit condition is driven by the output load, not any internal frequency variation signal generated by a frequency variation circuit. The patent specifically distinguishes such a load dependent change from the invention. ['366 patent at col. 3, lines 40 46.] 116. If Dr. Horowitz meant to identify the externally applied on/off signal, then that
would be incorrect also. Such a signal would not be generated by a frequency variation circuit (internal or external), and would not result in any EMI improvement. 117. The oscillator shown in these references operates at a fixed frequency during
normal operation and at a lower fixed frequency if the feedback indicates a short circuit or the part is powered down. This can't possibly do anything to solve the EMI problem, which is the purpose of the invention. 118. With respect to claims 4 and 13, the soft start circuitry of these references is not
the same as the corresponding structure or equivalent. These references use an external capacitor, different and not equivalent to disclosed structure (distinguished from the invention as described above). This is the same as the Electronic Design article and several other references discussed above, which were before the Examiner when he allowed the claims. These references
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also use a switching circuit in combination with an external compensation capacitor, and do not compare a frequency variation signal to an oscillator ramp signal. 119. Dr. Horowitz claims that it is inherent or obvious that the Stasi circuit could be
used in an AC mains flyback application as required by claims 9 and 17. This is not correct. The absolute maximum allowed switch voltage for the Stasi circuit is 70V. [FCS0524438.] The Stasi circuit would be destroyed if it were used in an AC mains application (85-265V). d. 120. '995 patent + AN-918 + LM3001/3101
These references are missing the frequency variation circuit and frequency
variation signal of claims 1, 2, 4, 7, 9, 10, 11, 13, 16, and 17. They are also missing the oscillator with a frequency that varies over a frequency range according to the frequency variation signal of these same claims. 121. The LM3001 does not have the claimed frequency variation signal; it operates
with a lower frequency only during an output short circuit. This is not the frequency variation circuit and signal of the `851 patent. See the discussion above with respect to the Stasi circuit. In addition, the LM3001 uses external resistors as part of it's short circuit frequency shift circuit, unlike the internal frequency variation circuit disclosed in the `366 patent. 122. The LM3001 doesn't have any frequency variation signal, and Dr. Horowitz
doesn't say that it does. 123. The `995 circuit has a short-circuit frequency shift circuit like the LM3101, and
shares the same deficiencies with respect to the `851 claims. 124. The circuitry Dr. Horowitz discusses with respect to frequency variation responds
to output load variations, precisely what the patent says it's not doing. These circuits reduce operating frequency as a function of the output to prevent runaway associated with a short circuit output. This is not cyclical frequency variation to reduce EMI in normal operation as claimed. 32
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These circuits operate with a fixed frequency during normal operation and do not achieve the goal of EMI reduction achieved with the patented frequency variation circuit and signal. The '995 patent states: During normal operating conditions, e.g., when Vout is approximately 5 Volts, and the load current is within the normal operating range, the oscillator output Vosc has a constant frequency. ['995 patent at col. 7, line 66 col. 8, line 2.] 125. With respect to claims 2 and 16, Dr. Horowitz resorts to his "inherent or
obvious" argument." He is not correct. The oscillator in these references uses external components for programming of its frequency. Thus putting those components inside the chip can't be inherent. Nor would it be obvious. Putting those components inside the chip would totally defeat the programmability set out by the reference. 126. These references are also missing the soft start circuit of claims 4 and 13. The
LM3001 and LM3101 and the `995 circuit all have external capacitors that operate to effect the feedback loop as with other conventional soft start features. Dr. Horowitz does not identify a signal that instructs the drive circuit to discontinue the drive signal according to a magnitude of a frequency variation signal as required by claims 4 and 13. Nor does he identify any frequency variation signal. Dr. Horowitz merely recites the claim language linking soft start and frequency variation and opines that it's in these references. It isn't. I reserve the right to respond when or if Dr. Horowitz identifies any of what he claims is in these references. e. 127. TEA2262
The TEA2262 is missing the frequency variation circuit and frequency variation
signal of claims 1, 2, 4, 7, 9, 10, 11, 13, 16, and 17. It is also missing the oscillator with a frequency that varies over a frequen