IN THE UNITED STATES PATENT AND TRADEMARK OFFICE
`
`
`Byron Hourmand
`In re Patent of:
`5,796,183 Atty. Docket No.: 39521-0062IP2
`U.S. Patent No.:
`August 18, 1998
`
`Issue Date:
`Appl. Serial No.: 08/601,268
`
`Filing Date:
`January 31, 1996
`
`Title:
`CAPACITIVE RESPONSIVE ELECTRONIC SWITCHING
`CIRCUIT
`
`
`Mail Stop Patent Board
`Patent Trial and Appeal Board
`U.S. Patent and Trademark Office
`P.O. Box 1450
`Alexandria, VA 22313-1450
`
`
`PETITION FOR INTER PARTES REVIEW OF UNITED STATES PATENT
`NO. 5,796,183 PURSUANT TO 35 U.S.C. §§ 311–319, 37 C.F.R. § 42
`
`
`
`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`TABLE OF CONTENTS
`
`I. 
`
`II. 
`
`SUMMARY OF THE ’183 PATENT ............................................................. 1 
`A.  Brief Description ....................................................................................... 1 
`REQUIREMENTS FOR IPR .......................................................................... 2 
`A.  Grounds for Standing ................................................................................ 2 
`B.  Challenge and Relief Requested ............................................................... 2 
`1.  Discretion under 35 U.S.C. § 314(a) ............................................... 5 
`C.  Level of Ordinary Skill in the Art ............................................................. 7 
`D.  Claim Construction ................................................................................... 7 
`1. 
`“providing signal output frequencies” (claims 27, 83) ................... 7 
`2. 
`“supply voltage” (claim 83) ............................................................ 9 
`3. 
`“coupled” (claims 27, 83) .............................................................. 10 
`III.  THE CHALLENGED CLAIMS ARE UNPATENTABLE .......................... 12 
`A.  [GROUND 1A] – Claims 32 and 36 are obvious over Caldwell and
`Ingraham ................................................................................................. 12 
`1. 
`Caldwell ......................................................................................... 12 
`2. 
`Ingraham ........................................................................................ 13 
`3. 
`Combination of Caldwell and Ingraham ....................................... 15 
`4. 
`Reasons to combine Caldwell and Ingraham ................................ 18 
`B.  [GROUND 1B] – Claim 28 is obvious over Caldwell, Ingraham, and
`Tucker ..................................................................................................... 56 
`1. 
`Tucker ............................................................................................ 56 
`2. 
`Combination of Caldwell, Ingraham, and Tucker ......................... 57 
`3. 
`Reasons to combine Caldwell, Ingraham, and Tucker .................. 58 
`C.  [GROUND 1C] – Claims 83-85, and 93 are obvious over Caldwell,
`Ingraham, and Redmayne ....................................................................... 61 
`1. 
`Redmayne ...................................................................................... 61 
`2. 
`Combination of Caldwell, Ingraham, and Redmayne ................... 61 
`3. 
`Reasons to combine Caldwell, Ingraham, and Redmayne ............ 62 
`D.  [GROUND 1D] – Claim 90 is obvious over Caldwell, Ingraham,
`Redmayne, and Schwarzbach ................................................................. 68 
`1. 
`Schwarzbach .................................................................................. 68 
`2. 
`Combination of Caldwell, Ingraham, Redmayne, and
`Schwarzbach .................................................................................. 69 
`Reasons to combine Caldwell, Ingraham, Redmayne, and
`Schwarzbach .................................................................................. 69 
`E.  [GROUND 1E] – Claim 91 is obvious over Caldwell, Ingraham,
`Redmayne, and Ingraham ’548 ............................................................... 71 
`
`3. 
`
`i
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`

`

`3. 
`
`1. 
`2. 
`
`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`Ingraham ’548 ............................................................................... 71 
`Combination of Caldwell, Ingraham, Redmayne, and Ingraham
`’548 ................................................................................................ 71 
`Reasons to combine Caldwell, Ingraham, Redmayne, and
`Ingraham ’548 ............................................................................... 72 
`F.  [GROUND 1F] – Claims 86-88 are obvious over Caldwell, Ingraham,
`Redmayne, and Meadows ....................................................................... 73 
`1.  Meadows ....................................................................................... 73 
`2. 
`Combination of Caldwell, Ingraham, Redmayne, and Meadows . 74 
`3. 
`Reasons to combine Caldwell, Ingraham, Redmayne, and
`Meadows ....................................................................................... 76 
`G.  [GROUND 1G] – Claim 92 is obvious over Caldwell, Ingraham,
`Redmayne, and Tucker ........................................................................... 79 
`1. 
`Combination of Caldwell, Ingraham, Redmayne, and Tucker, and
`reasons to combine ........................................................................ 79 
`IV.  FEES .............................................................................................................. 79 
`V. 
`CONCLUSION .............................................................................................. 80 
`VI.  MANDATORY NOTICES UNDER 37 C.F.R § 42.8(a)(1) ......................... 80 
`A.  Real Party-In-Interest Under 37 C.F.R. § 42.8(b)(1) .............................. 80 
`B.  Related Matters Under 37 C.F.R. § 42.8(b)(2) ....................................... 80 
`A.  Lead And Back-Up Counsel Under 37 C.F.R. § 42.8(b)(3) ................... 80 
`B.  Service Information ................................................................................ 81 
`
`
`
`ii
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`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`
`EXHIBITS
`
`U.S. Patent No. 5,796,183 to Hourmand (“the ’183 patent”)
`
`Excerpts from the Prosecution History of the ’183 Patent (“the
`Prosecution History”)
`
`APPLE-1001
`
`APPLE-1002
`
`APPLE-1003
`
`Declaration of Dr. Phillip Wright
`
`APPLE-1004
`
`U.S. Patent No. 5,572,205 to Caldwell (“Caldwell”)
`
`APPLE-1005
`
`U.S. Patent No. 4,561,002 to Chiu (“Chiu”)
`
`APPLE-1006
`
`Prosecution History of Reexamination Control No. 90/012,439
`
`APPLE-1007
`
`Prosecution History of Reexamination Control No. 90/013,106
`
`APPLE-1008
`
`U.S. Patent No. 4,560,954 to Leach (“Leach”)
`
`APPLE-1009
`
`U.S. Patent No. 4,878,107 to Hopper (“Hopper”)
`
`APPLE-1010
`
`U.S. Patent No. 5,341,036 to Wheeler (“Wheeler”)
`
`APPLE-1011
`
`U.S. Patent No. 4,237,421 to Waldron (“Waldron”)
`
`APPLE-1012
`
`U.S. Patent No. 5,650,597 to Redmayne (“Redmayne”)
`
`APPLE-1013
`
`U.S. Patent No. 4,922,061 to Meadows (“Meadows”)
`
`APPLE-1014
`
`U.S. Patent No. 4,418,333 to Schwarzbach (“Schwarzbach”)
`
`APPLE-1015
`
`U.S. Patent No. 4,293,734 to Pepper (“Pepper”)
`
`APPLE-1016
`
`U.S. Patent No. 4,731,548 to Ingraham (“Ingraham ’548”)
`
`APPLE-1017
`
`U.S. Patent No. 4,758,735 to Ingraham (“Ingraham”)
`
`APPLE-1018
`
`U.S. Patent No. 5,189,417 to Caldwell (“Caldwell ’417”)
`
`iii
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`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`U.S. Patent No. 4,308,443 to Tucker (“Tucker”)
`
`APPLE-1019
`
`APPLE-1020
`
`U.S. Patent No. 4,290,061 to Serrano (“Serrano”)
`
`
`
`APPLE-1021
`
`U.S. Patent No. 4,845,630 to Stephens (“Stephens”)
`
`APPLE-1022
`
`U.S. Patent No. 5,048,019 to Albertsen (“Albertsen”)
`
`APPLE-1023
`
`U.S. Patent No. 5,632,039 to Walker (“Walker”)
`
`APPLE-1024
`
`U.S. Patent No. 5,508,653 to Chu (“Chu”)
`
`APPLE-1025
`
`U.S. Patent No. 5,087,825 to Ingraham (“Ingraham ’825”)
`
`APPLE-1026
`
`U.S. Patent No. 4,649,323 to Pearlman (“Pearlman”)
`
`APPLE-1027
`
`U.S. Patent No. 5,311,392 to Kinney (“Kinney”)
`
`APPLE-1028
`
`U.S. Patent No. 4,707,852 to Jahr (“Jahr”)
`
`APPLE-1029
`
`U.S. Patent No. 5,638,444 to Chou (“Chou”)
`
`APPLE-1030
`
`U.S. Patent No. 5,063,383 to Bobba (“Bobba”)
`
`APPLE-1031
`
`U.S. Patent No. 4,903,251 to Chapman (“Chapman”)
`
`
`
`
`
`iv
`
`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`Apple Inc. (“Petitioner” or “Apple”) petitions for Inter Partes Review
`
`(“IPR”) of claims 28, 32, 36, 83-88, and 90-93 (“the Challenged Claims”) of U.S.
`
`Patent No. 5,796,183 (“the ’183 patent”).
`
`I.
`
`SUMMARY OF THE ’183 PATENT
`A. Brief Description
`The ’183 patent relates to a capacitive responsive electronic switching
`
`circuit. APPLE-1001, Abstract. As shown in Figure 4, the circuit includes
`
`oscillator 200 (shown in blue) providing a periodic output signal, input touch
`
`terminal 450 (green) for an operator to provide an input by proximity or touch, and
`
`touch circuit 400 (orange) that provides a detection signal to microcontroller 500
`
`(yellow) that receives the output signal from the oscillator. Id., FIG. 4, 7:22-24,
`
`12:6-28; APPLE-1003, [27]-[34] (“Technology Overview”).
`
`1
`
`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`
`APPLE-1001, FIG. 4 (annotated)
`
`
`
`II. REQUIREMENTS FOR IPR
`A. Grounds for Standing
`Apple certifies that the ’183 Patent is available for IPR. This petition is
`
`being filed within one year of service of a complaint against Apple on November
`
`29, 2017 in the Eastern District of Michigan. Apple is not barred or estopped from
`
`requesting this review on the grounds identified below.
`
`B. Challenge and Relief Requested
`Apple requests IPR of the Challenged Claims on the following grounds:
`
`2
`
`

`

`Ground
`1A
`1B
`
`Claims
`32, 36
`28
`
`1C
`
`1D
`
`1E
`
`1F
`
`1G
`
`83-85, 93
`
`90
`
`91
`
`86-88
`
`92
`
`
`
`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`§ 103 Basis
`Obvious over Caldwell and Ingraham
`Obvious over Caldwell, Ingraham, and
`Tucker
`Obvious over Caldwell, Ingraham, and
`Redmayne
`Obvious over Caldwell, Ingraham,
`Redmayne, and Schwarzbach
`Obvious over Caldwell, Ingraham,
`Redmayne, and Ingraham ’548
`Obvious over Caldwell, Ingraham,
`Redmayne, and Meadows
`Obvious over Caldwell, Ingraham,
`Redmayne, and Tucker
`
`The earliest priority date of the ’183 patent is January 31, 1996 (the “Critical
`
`Date”). APPLE-1002. The ’183 patent was subject to a previous IPR challenge
`
`filed by Samsung. Samsung v. UUSI, IPR2016-00908, Paper 2 (PTAB April 15,
`
`2016).
`
`The cited references are prior art as shown:
`
`Reference
`Caldwell (APPLE-1004)
`Redmayne (APPLE-1012)
`Meadows (APPLE-1013)
`Schwarzbach (APPLE-1014)
`Ingraham ’548 (APPLE-1016)
`Ingraham (APPLE-1017)
`
`35 U.S.C. §
`102(e)
`102(e)
`102(b)
`102(b)
`102(b)
`102(b)
`
`Qualifying date
`03/29/1993 (filed)
`01/20/1995 (filed)
`05/01/1990 (issued)
`11/29/1983 (issued)
`03/05/1988 (issued)
`07/19/1988 (issued)
`
`3
`
`

`

`Tucker (APPLE-1019)
`
`
`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`12/29/1981 (issued)
`
`102(b)
`
`Caldwell, Ingraham, Ingraham ’548, and Tucker were listed in an IDS
`
`during prosecution of the ’183 patent, but not relied on during that prosecution nor
`
`during subsequent Patent Owner-initiated reexamination. APPLE-1001, Face;
`
`APPLE-1002, 302, 307; APPLE-1006; APPLE-1007. The remaining references
`
`were not considered.
`
`Caldwell, Ingraham, and Ingraham ’548 are the only references that were
`
`relied on by Samsung in the prior IPR. Samsung v. UUSI, Paper 2. However, this
`
`Petition relies on different disclosures from these references, and presents them in
`
`a different light.
`
`For example, this Petition relies on Caldwell as a primary reference, while
`
`the Samsung IPR used Caldwell merely “to corroborate that one skilled in the art
`
`would have had the knowledge and capability to implement” its proposed
`
`combination, and not to “disclose any of the features of the challenged claims.”
`
`Samsung v. UUSI, Paper 2, 45, note 13.
`
`The Samsung IPR relied on Ingraham and Ingraham ’548 throughout, but
`
`did not rely on these references for the claim features to which they are mapped in
`
`this Petition. Section III, [27f] (relying on Ingraham for “a presence of an
`
`operator's body capacitance to ground coupled to said first and second touch
`
`4
`
`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`terminals when proximal or touched by the operator”); [91a] (relying on Ingraham
`
`’548 for “a voltage regulator supply voltage”).
`
`1.
`Discretion under 35 U.S.C. § 314(a)
`The Board has discretion “to deny a petition that challenges a patent that was
`
`previously challenged before the Board.” Shenzhen Silver Star Intelligent Tech. v.
`
`iRobot, IPR2018-00898, Paper 9, 6 (10/01/2018); Gen. Plastic Indus. v. Canon
`
`Kabushiki Kaisha, IPR2016-01360, Paper 19, 8 (09/06/2017). The Board has
`
`provided a non-exhaustive list of factors it considers when determining whether to
`
`apply this discretion. Gen. Plastic, Paper 19, 16. These factors weigh heavily
`
`against denial because any delay in Apple’s IPR relative Samsung’s IPR was
`
`caused by Patent Owner’s delay in bringing suit against Apple. Patent Owner
`
`waited over two years and until after the Samsung IPR concluded before suing
`
`Apple. Under these circumstances, rewarding Patent Owner’s delay and denying
`
`this petition for discretionary reasons would be unfair to Apple.
`
`Specifically, the first General Plastic factor weighs against denial, because
`
`Apple has not filed any previous petition challenging the ’183 patent. Gen.
`
`Plastic, Paper 19, 16. The second factor also weighs against denial, because Apple
`
`did not know of any of the prior art references relied on in this Petition when
`
`Samsung filed its IPR and, because Apple had not been sued, had no reason to
`
`identify prior art applicable to the ’183 patent at that time. Gen. Plastic, Paper 19,
`
`5
`
`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`
`16.
`
`The fourth General Plastic factor also weighs against denial, because the
`
`prior art relied on in this Petition was identified by prior art searching and review
`
`that was not conducted (and that Apple had no reason to conduct) until after suit
`
`was filed against Apple and the Samsung IPR had concluded. Gen. Plastic, Paper
`
`19, 16.
`
`In addition, the fifth General Plastic factor weighs against denial, because
`
`any delay between Samsung’s IPR and this IPR was due to Patent Owner’s delay
`
`in filing suit against Apple. Gen. Plastic, Paper 19, 16.
`
`The sixth and seventh factors either favor institution or are at worst neutral.
`
`Gen. Plastic, Paper 19, 16.
`
`Further, in Shenzhen, the Board considered “the extent to which the
`
`petitioner and any prior petitioner(s) were similarly situated defendants.”
`
`Shenzhen, Paper 9, 7. The “purpose” of this factor “is to discourage tactical filing
`
`of petitions over time by parties that faced the same threat at the same time.” Id.,
`
`14.1 Here, Apple did not face “the same threat at the same time” as Samsung
`
`because Patent Owner waited to sue Apple over two years after it filed suit against
`
`Samsung and over a month after the Samsung IPR concluded.
`
`
`1 All emphasis added unless otherwise indicated.
`
`6
`
`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`Because these factors weigh against denial, the Board should not exercise its
`
`discretion to deny institution.
`
`C. Level of Ordinary Skill in the Art
`A person of ordinary skill in the art as of the Critical Date of the ’183 patent
`
`(hereinafter a “POSITA”) would have had at least a Bachelor of Science degree in
`
`electrical engineering or a related technical field, and two or more years of
`
`experience in electrical circuits and sensor systems. APPLE-1003, [22]; APPLE-
`
`1001, (Background).
`
`D. Claim Construction
`Petitioner proposes construction of the terms below. The remaining terms
`
`do not require construction. Vivid Techs. v. Am. Sci. & Eng’g, 200 F.3d 795, 803
`
`(Fed. Cir. 1999) (only claim terms in controversy need to be construed, and only to
`
`the extent necessary to resolve the controversy). Petitioner reserves the right to
`
`respond to any constructions offered by Patent Owner or adopted by the Board.
`
`Petitioner is not waiving any arguments concerning indefiniteness or claim scope
`
`that may be raised in litigation.
`
`1.
`“providing signal output frequencies” (claims 27, 83)
`Claim 83 recites “the microcontroller selectively providing signal output
`
`frequencies to a closely spaced array of input touch terminals of a keypad.” Claim
`
`85, which depends from 83, states that “the signal output frequencies have a same
`
`hertz value.” Because it is a dependent claim, claim 85 further limits the claim
`
`7
`
`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`from which it depends and independent claim 83 must be interpreted to encompass
`
`the scope of claim 85. Thus, “providing signal output frequencies” in claim 83
`
`must be interpreted to encompass the situation where “each signal output
`
`frequency” of the provided signal output frequencies “has the same hertz value.”
`
`37 C.F.R. 1.75(c).
`
`In addition, a POSITA would have understood that two frequencies that
`
`have “the same hertz value” are the same frequency. APPLE-1003, [59]. Thus,
`
`the claimed “signal output frequencies” can be the same, and need not be different
`
`frequencies. Id.
`
`Similarly, claim 86, which depends from 83, states that “each signal output
`
`frequency is selected from a plurality of hertz values.” Thus, “providing signal
`
`output frequencies” in claim 83 must also be interpreted to encompass selection of
`
`each frequency from a plurality of hertz values.
`
`As claims 85 and 86 confirm, the limitation “providing signal output
`
`frequencies” in claim 83 should be construed to include “providing signal output
`
`frequencies, wherein each signal output frequency has a same hertz value or is
`
`selected from a plurality of hertz values.” APPLE-1003, [58]-[61].
`
`Claim 27 also recites “providing signal output frequencies.” Because there
`
`is no indication that this identical claim language should have a different meaning,
`
`“providing signal output frequencies” in claim 27 should be construed consistent
`
`8
`
`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`with the identical language in claim 83. Pods, Inc. v. Porta Stor, Inc., 484 F. 3d
`
`1359 (Fed. Cir. 2007); APPLE-1003, [62].
`
`2.
`“supply voltage” (claim 83)
`Claim 83 recites “the microcontroller selectively providing signal output
`
`frequencies ... wherein a peak voltage of the signal output frequencies is greater
`
`than a supply voltage.” The recitation of “a supply voltage” is properly construed
`
`to be a supply voltage of the microcontroller, as opposed to a supply voltage for
`
`another component in the touch circuit.
`
`The placement of the term within a wherein clause describing the
`
`microcontroller supports this interpretation. APPLE-1001, claim 83. In addition,
`
`the supply voltage being compared to the “signal output frequencies” provided by
`
`the microcontroller in claim 83 is indicative that the recited supply voltage is a
`
`supply voltage of the microcontroller. APPLE-1001, claim 83; APPLE-1003, [63]-
`
`[64].
`
`In the previous IPR challenge, the Board determined: “based on the context
`
`of the supply voltage limitations in [claim 83], that one of ordinary skill in the art
`
`would understand the term ‘supply voltage’ as referring to a supply voltage of the
`
`claimed microcontroller.” Samsung v. UUSI, IPR2016-00908, Paper 12, 10. The
`
`Board found that the term’s inclusion within a claim limitation reciting “a
`
`microcontroller” meant that the recited “supply voltage” referred to a supply
`
`9
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`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`voltage of the microcontroller rather than to some other circuit component (such as
`
`the oscillator). Id.
`
`Accordingly, the term “a supply voltage” in claim 83 should be construed to
`
`mean “a supply voltage of the microcontroller.” APPLE-1003, [63]-[66].
`
`3.
`“coupled” (claims 27, 83)
`Claims 27 and 83 recite various components “coupled” to other components.
`
`For example, claim 27 recites “a detector circuit coupled to said oscillator.” The
`
`’183 patent discloses that such coupling may be direct (e.g., two components
`
`connected by a wire) or indirect (e.g., two components connected by a path
`
`through other components).
`
`For example, the ’183 patent describes that “[o]scillator 1200 is preferably
`
`comprised of a first invertor gate 1210 having [its] input coupled to [its] output via
`
`resistors 1214 and 1216[.]” APPLE-1001, 20:6-8. FIG. 13 shows this
`
`configuration:
`
`10
`
`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`
`
`
`APPLE-1001, FIG. 13 (annotated)
`
`The ’183 patent includes several other examples of indirect coupling
`
`between components. APPLE-1001, 12:60-62, 13:46-48.
`
`Accordingly, the term “coupled” should be construed to include indirect
`
`coupling via intervening components. APPLE-1003, [67]-[69].
`
`11
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`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`III. THE CHALLENGED CLAIMS ARE UNPATENTABLE
`A.
`[GROUND 1A] – Claims 32 and 36 are obvious over
`Caldwell and Ingraham
`1.
`Caldwell
`Caldwell teaches a “touch control system that is responsive to a user input
`
`selection” that “includes an electrically non-conducting substrate, such as glass
`
`ceramic, and at least one capacitive-responsive touchpad on the substrate.”
`
`APPLE-1004, Abstract. Caldwell describes “a high frequency line driver 32” (an
`
`oscillator) that produces a “source signal having a primary frequency that is greater
`
`than 150 kHz … [and] applied to one portion of the touchpad.” Id. “The touchpad
`
`couples the electrical signal to another portion of the touchpad in order to develop
`
`a detection signal, which is decoded in order to determine the presence of the
`
`capacitance of a user.” Id.
`
`Caldwell describes that “[e]ach touch pad 14 includes a first portion
`
`composed of an electrically conducting element 16a” (a first electrode) “and a
`
`second portion composed of an electrically conducting element 16b” (a second
`
`electrode) “affixed to a surface 18 of substrate 12” and “a user contact pad 20” (a
`
`third electrode) “overlying the conductive elements 16a and 16b.” Id., 3:60-66.
`
`FIG. 2 from Caldwell shows example touch pad 14. APPLE-1003, [70]-[71].
`
`12
`
`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`
`APPLE-1004, FIG. 2 (annotated)
`
`
`
`2.
`Ingraham
`Ingraham is emblematic of well-known prior art touch sensors described in
`
`the “Background” section of the ’183, which specifically cites “U.S. Pat. No.
`
`4,758,735” (Ingraham) as disclosing “capacitive touch switches” that rely “on the
`
`change in capacitive coupling between a touch terminal and ground” in which “the
`
`operator need not come in conductive contact with the touch terminal but rather
`
`only in close proximity to it” for detection to occur. APPLE-1001, 3:44-63. The
`
`13
`
`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`’183 patent further states that the “specific touch detection method” it describes
`
`“has similarities to the devices of” Ingraham. APPLE-1001, 5:43-44.
`
`In particular, Ingraham describes “a touch controlled electrical switching
`
`circuit” that includes an “oscillator circuit” producing a “square wave” detection
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`signal. APPLE-1017, 2:21-25. A “touch plate 15 ... made of an electrically
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`conductive material” (i.e., an electrode) is “electrically coupled” to the path of the
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`detection signal. Id., 2:9-15. The “oscillator ... applies” the detection “signal to
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`[the] touch plate [15].” Id., 1:42-44. When “a person touches plate 15,” the
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`voltage of the detection signal is decreased by the introduction of the person’s
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`“body capacitance” to ground. Id., 2:56-58. This decrease in voltage is measured
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`by a “detector circuit” coupled to the touch plate 15 to detect a touch input.
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`APPLE-1017, 1:42-44, claim 8, FIG. 1; APPLE-1003, [72]-[74]. FIG. 1 from
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`Ingraham shows touch plate 15 being touched by a person, thereby introducing
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`body capacitance to ground (11, 14):
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`14
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`

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`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`
`APPLE-1017, FIG. 1 (annotated)
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`
`
`Ingraham further teaches that “it is not necessary for the operator to actually
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`touch the electrically conductive plate 15 but only come sufficiently close to add
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`the body capacitance 14” to the circuit in order to detect a touch input. Id., 2:15-
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`18.
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`3.
`Combination of Caldwell and Ingraham
`In the combination, Ingraham’s touch plate 15 replaces each touch pad 14 of
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`Caldwell including “the conductive elements 16a and 16b” and the “user contact
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`pad 20.” APPLE-1004, 3:60-66, FIG. 2; APPLE-1017, 2:9-15, 2:56-58, FIG. 1;
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`15
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`

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`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`APPLE-1003, [75]. Caldwell’s FIG. 5 shows this configuration:
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`APPLE-1004, FIG. 5 (annotated)
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`
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`As shown, in the combination, Ingraham’s touch plate 15 is connected to the
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`drive lines 52a-52c of Caldwell and receives the detection signal from the high
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`frequency line driver 46. APPLE-1003, [76]. The touch plate 15 also connects
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`16
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`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`through sense lines 54a-54d to the detector circuit of Caldwell. Id.
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`In Ingraham, introduction of a user’s body capacitance to ground at one of
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`the touch plates lowers the voltage of the signal provided to the detector circuit.
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`APPLE-1017, 2:56-58. Thus, the impact on the signal coming out of the
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`Caldwell’s touch pad 14 when it is touched (i.e., Caldwell’s oscillator signal with a
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`lowered voltage) is the same as the impact on the signal coming out of Ingraham’s
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`touch plate 15 when it is touched (i.e., Ingraham’s oscillator signal with a lowered
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`voltage). APPLE-1004, 2:21-25, 2:65-66, 4:65-5:2; APPLE-1017, 2:56-58.
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`Accordingly, in the combination, the introduction of a user’s body capacitance to
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`ground at one of Ingraham’s touch plates 15 lowers the voltage of the signal
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`provided from Caldwell’s high frequency line driver 46 to the detector circuit. Id.
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`Because the impact on the signal is the same with the substitution of
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`Ingraham’s touch plates 15, the detector circuit of Caldwell detects this decrease in
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`voltage in the same way it detects the decrease in voltage caused by a user
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`touching the user contact pad of Caldwell’s touch pad 14. APPLE-1004, 2:21-25.
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`A POSITA would have understood that a user touching one of Ingraham’s touch
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`plates 15 may decrease the voltage of the detection signal by a different amount
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`than the user touching one of Caldwell’s touch pads 14. As Dr. Wright explains, a
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`POSITA would have been readily able to address this potential difference by
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`recalibrating the threshold voltage of Caldwell’s detector circuit. APPLE-1003,
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`17
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`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`[77]-[78]; APPLE-1001 (Background section), 4:8-10 (it was known to “adjust the
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`detection sensitivity by adjusting the threshold voltage to which the sensed voltage
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`is compared”). Such a recalibration would have been routine for a POSITA to
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`implement, and thus would not serve as a technical impediment to the combination
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`or lead a POSITA away from the combination. Id.
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`Accordingly, the combination involves a simple substitution of one type of
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`known touch pad (Caldwell’s touch pad 14) with another (Ingraham’s touch plate
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`15). In the combination, a POSITA would have known to (1) substitute each touch
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`pad 14 of Caldwell with a touch plate 15 of Ingraham, (2) apply Caldwell’s high
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`frequency line driver 46 to the touch plates 15, and (3) adjust the threshold used in
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`Caldwell’s detector circuit as needed. Caldwell’s detector circuit would then
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`operate as described in Caldwell or touch at the touch plates 15. APPLE-1003,
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`[79].
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`4.
`Reasons to combine Caldwell and Ingraham
`A POSITA would have been motivated to substitute touch plates of
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`Ingraham for touch pads of Caldwell to obtain several advantages of the touch
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`sensor configuration described in Ingraham. For example, a POSITA would have
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`understood that incorporating the touch plate of Ingraham would have provided
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`improved proximity detection (for example, proximity detection at a greater
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`effective range, and at a higher signal-noise ratio) compared to Caldwell alone.
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`18
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`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`APPLE-1003, [80]. Indeed, the ’183 patent itself recognizes that Ingraham has the
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`advantage that an “operator need not come in conductive contact with the touch
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`terminal but rather only in close proximity to it.” APPLE-1001, 3:56-59
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`(describing this as a “major advantage” of Ingraham); APPLE-1017, 2:15-20, 2:48-
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`52. A POSITA would have recognized that this advantage would have made the
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`keypad of Caldwell more responsive to user input, thereby making it easier for an
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`operator to use under a variety of conditions. APPLE-1003, [80].
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`In addition, the touch plate described in Ingraham requires fewer electrodes
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`than the one described in Caldwell. Compare APPLE-1017, 2:11-15, FIG. 1 (a
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`single electrically-conductive “touch plate 15”) to APPLE-1004, 3:64-66, FIG. 4
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`(two “conductive elements 16a and 16b” and a “user contact pad 20”); APPLE-
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`1017, 3:55-58; APPLE-1015, 8:55-56; APPLE-1009, 3:9-23. This simplification
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`of the touch pad circuit would have led to a reduction in the manufacturing cost of
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`the touch circuit (as two electrodes are eliminated from each touch pad), which
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`also would have motivated a POSITA to perform the modification. Id.; APPLE-
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`1003, [81].
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`Although the ’183 patent describes potential issues related to using multiple
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`touch pads of the type described in Ingraham “placed in close proximity” to one
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`another, such as susceptibility to the effects of contaminants on the surface of the
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`touch pads, the techniques of Caldwell address this issue. APPLE-1001, 4:18-27;
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`19
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`

`

`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`APPLE-1004, 5:15-18. Specifically, Caldwell describes that using oscillator
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`“frequencies of 150 kHz and above” in the touch circuit provides “increased
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`immunity to cross-coupling between adjacent” touch pads “due to liquids, such as
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`water, on substrate 12.” APPLE-1004, 5:15-18; APPLE-1001, 5:49-53 (describing
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`an approach similar to Caldwell’s for “minimiz[ing] the effects of surface
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`contamination”); APPLE-1003, [82]. As Dr. Wright explains, a POSITA would
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`have seen Ingraham’s touch plates 15 as suitable for operation at the frequencies
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`and voltage levels used in Caldwell’s touch circuit, and a POSITA would have
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`retained these frequencies and voltage levels in the combination to retain
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`Caldwell’s benefits of improved contaminant performance. Id.2
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`The results of the combination also would have been predictable because
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`sensors detecting a user’s body capacitance to ground, such as the sensors
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`described by Ingraham, were widely used in touch sensing circuits like the one
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`described in Caldwell prior to the Critical Date. APPLE-1017, 2:15-20, 3:55-58;
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`2 The ’183 patent describes the circuit of Ingraham as operating at a higher
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`voltage than the circuit of the ’183 patent. APPLE-1001, 6:8-13. However,
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`Ingraham does not describe a particular supply or peak voltage value for its circuit,
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`and its touch plate 15 would have been responsive to the voltage levels described
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`by Caldwell. APPLE-1017; APPLE-1003, [82].
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`20
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`

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`Attorney Docket No. 39521-0062IP2
`IPR of U.S. Patent No. 5,796,183
`APPLE-1001, 3:44-59; APPLE-1025, 3:30-37, FIG. 1; APPLE-1016, 2:33-42,
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`FIG. 1. Indeed, the ’183 patent describes several such touch sensing circuits in its
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`“Background” section, including the touch circuit of Ingraham. APPLE-1001,
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`3:44-63 (describing Ingraham as a “capacitive touch switch[] rel[ying] on the
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`change in capacitive coupling between a touch terminal and ground”). As
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`recognized in the ’183 patent’s “Background” section, the technique described by
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`Ingraham is one of a limited number of known “methodologies” for achieving
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`“capacitive touch switches.” APPLE-1001, 3:12-63. With this background, and in
`