Maxim Integrated Products, Inc.

Patent Trials and Appeals Board

Jun 2, 2020

2019003901 (P.T.A.B. Jun. 2, 2020)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
14/483,402 09/11/2014 Jiangang Liu 20057-1814 4530
69569 7590 06/02/2020
NORTH WEBER & BAUGH LLP
3260 Hillview Avenue, 1st Floor
Pitman
PALO ALTO, CA 94304
EXAMINER
FAIRBANKS, BRENT ALAN
ART UNIT PAPER NUMBER
2862
NOTIFICATION DATE DELIVERY MODE
06/02/2020 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
docket1@northweber.com
mnorth@northweber.com
mnorth@northweber.com
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte JIANGANG LIU and JASON ALLEN WORTHAM
____________

Appeal 2019-003901
Application 14/483,402
Technology Center 2800
____________

Before JAMES C. HOUSEL, DONNA M. PRAISS, and
MONTÉ T. SQUIRE, Administrative Patent Judges.

SQUIRE, Administrative Patent Judge.

DECISION ON APPEAL1

Appellant2 appeals under 35 U.S.C. § 134(a) from the Examiner’s
final rejection of claims 1–20, which are all of the claims pending in this
application. We have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.

1 In this Decision, we refer to the Specification filed Sept. 11, 2014
(“Spec.”); Final Office Action dated Sept. 5, 2018 (“Final Act.”); Advisory
Action dated Nov. 28, 2018 (“Advisory Act.”); Appeal Brief filed Feb. 4,
2019 (“Appeal Br.”); Examiner’s Answer dated Apr. 9, 2019 (“Ans.”); and
Reply Brief filed Apr. 22, 2019 (“Reply Brief”).
2 We use the word “Appellant” to refer to “applicant” as defined in
37 C.F.R. § 1.42(a). Appellant identifies Maxim Integrated, Inc. as the real
party in interest. Appeal Br. 3.
Appeal 2019-003901
Application 14/483,402

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CLAIMED SUBJECT MATTER
The invention relates to isolation measuring systems and methods in a
vehicle having a high voltage (HV) system and a low voltage (LV) system,
and, more particularly, to measuring isolation impedance, including direct
current (DC) resistance and alternating current (AC) impedance. Spec. ¶¶ 2,
6; Abstract.
Claim 1 illustrates the subject matter on appeal and is reproduced
below from the Claims Appendix to the Appeal Brief:
1. A method for determining isolation impedance, the
method comprising:
receiving at a voltage node a waveform signal that is
representative of a first voltage; and
extracting amplitude and phase information from the
waveform signal;
utilizing the amplitude and phase information to determine
an isolation impedance between a second voltage and a ground
potential, the second voltage being coupled to the voltage node
and being higher than the first voltage.
Appeal Br. 23 (key disputed claim language italicized and bolded).
REFERENCES
The Examiner relies on the following prior art references as evidence
in rejecting the claims on appeal:
Name Reference Date
Janke et al. (“Janke”) US 5,450,328 Sept. 12, 1995
Pickerd US 2003/0030426 A1 Feb. 13, 2003
Srinivasan et al.
(“Srinivasan”)
US 2006/0170397 A1 Aug. 3, 2006
Wolft US 2013/0035819 A1 Feb. 7, 2013
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REJECTIONS
On appeal, the Examiner maintains (Ans. 3) the following rejections:3
1. Claims 1, 2, 5, 9–12, 15, 16, and 19 are rejected under
35 U.S.C. §§ 102(a)(1) and 102(a)(2) as being anticipated by Srinivasan
(“Rejection 1”). Final Act. 13.
2. Claims 3, 4, 13, and 14 are rejected under 35 U.S.C. § 103 as
being unpatentable over Srinivasan in view of Pickerd (“Rejection 2”). Id.
at 17.
3. Claim 6 is rejected under 35 U.S.C. § 103 as being unpatentable
over Srinivasan in view of Wolft (“Rejection 3”). Id. at 20.
4. Claims 7, 8, 17, 18, and 20 are rejected under 35 U.S.C. § 103
as being unpatentable over Srinivasan in view of Janke (“Rejection 4”). Id.
at 21.
OPINION
Rejection 1
The Examiner rejects claims 1, 2, 5, 9–12, 15, 16, and 19 under
35 U.S.C. §§ 102(a)(1) and 102(a)(2) as being anticipated by Srinivasan.
Final Act. 13–17. In response to the Examiner’s rejection, Appellant
presents separate arguments for the patentability of the independent claims 1
and 10 under two separate headings in the Appeal Brief (Appeal Br. 19, 20),
which we address in turn below.

3 The Examiner’s § 112 and § 101 rejections are withdrawn at page 3 of the
Answer.
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Application 14/483,402

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Claim 1
The Examiner determines that Srinivasan describes a method
disclosing each limitation of claim 1 and anticipates the claim. Final
Act. 13–14. Regarding the “extracting amplitude and phase information
from the waveform signal” recitation of claim 1, the Examiner relies
principally on paragraphs 19 and 47 of Srinivasan for disclosing that
limitation of the claim. Id. at 13; Ans. 5. In particular, the Examiner finds
Srinivasan’s paragraph 19 teaches
EIS is a well-known electrochemical technique and has
been in use since the 1940s to measure the internal
impedance of electrochemical cells. It uses a
small-amplitude (<1 millivolt) ac voltage source to perturb
the electrochemical cell. In response, the cell generates an
ac current at the same frequency, whose magnitude and
phase can be utilized to ascertain the battery’s impedance
at that particular frequency.
Ans. 5 (quoting Srinivasan ¶ 19 with emphasis).
The Examiner further finds Srinivasan’s paragraph 47 teaches the use
of Fourier transform techniques to derive an impedance of a battery based on
current and frequency spectrums and the transformed current and frequency
spectrums contain amplitude and phase information. Id. at 6. In particular,
the Examiner relies on the portion of paragraph 47 of Srinivasan which
states:
Modules 802 and 806 can use fast Fourier transform
techniques to derive their respective frequency spectrums.
A module 812 derives an impedance 814 of battery 202 as
a function of current and voltage frequency spectrums 804
and 808.
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Id. at 6 (quoting Srinivasan ¶ 47). Based on the above findings, the
Examiner determines Srinivasan discloses “extracting amplitude and phase
information from the waveform signal,” as recited in the claim.
Appellant argues the Examiner’s rejection of claim 1 should be
reversed because Srinivasan does not disclose the “extracting amplitude and
phase information from the waveform signal” limitation of the claim.
Appeal Br. 19–20; Reply Br. 5–6. Appellant argues that Srinivasan teaches
using current and voltage frequency spectrums to derive a battery’s internal
impedance, in contrast to the claimed invention, which requires extracting
amplitude and phase information from a waveform signal and utilizing the
amplitude and phase information to determine an isolation impedance.
Appeal Br. 19 (citing Srinivasan ¶ 47); see also id. at 20 (arguing “nowhere
Srinivasan mentions or suggests that it extracts amplitude and phase
information from a waveform signal or that it uses such information to
determine an isolation impedance”).
Appellant’s argument is persuasive because the Examiner has not
established by a preponderance of the evidence that Srinivasan discloses the
“extracting amplitude and phase information from the waveform signal”
limitation of the claim. See In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir.
1992) (“[T]he examiner bears the initial burden, on review of the prior
art . . . of presenting a prima facie case of unpatentability.”).
Anticipation requires a showing that each limitation of a claim is
disclosed in a single reference, either expressly or inherently. Perricone v.
Medicis Pharm. Corp., 432 F.3d 1368, 1369 (Fed. Cir. 2005). To establish
that a prior art reference inherently discloses a limitation, “the examiner
must provide a basis in fact and/or technical reasoning to reasonably support
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the determination that the allegedly inherent characteristic necessarily flows
from the teachings of the applied prior art.” Ex parte Levy, 17 USPQ2d
1461, 1464 (Bd. Pat. App. & Int. 1990) (citation omitted). Inherency “may
not be established by probabilities or possibilities. The mere fact that a
certain thing may result from a given set of circumstances is not sufficient.”
Continental Can Co. USA, Inc. v. Monsanto Co., 948 F.2d 1264, 1269 (Fed.
Cir. 1991) (quoting In re Oelrich, 666 F.2d 578, 581 (CCPA 1981)).
Here, the Examiner has not provided the requisite factual basis and/or
technical reasoning to support a finding that Srinivasan, either expressly or
inherently, discloses “extracting amplitude and phase information from the
waveform signal,” as recited in the claim. The portions of Srinivasan the
Examiner cites and principally relies upon in the rejection do not disclose
that limitation of the claim. See Srinivasan ¶¶ 19, 47. Although paragraph
19 of Srinivasan mentions that magnitude and phase can be utilized to
ascertain the battery’s internal impedance, the Examiner does not identify or
direct us to any specific description or discussion in that paragraph or
elsewhere in the reference, which expressly or inherently discloses
extracting amplitude and phase information from the waveform signal and
utilizing the extracted amplitude and phase information to determine
isolation impedance in the manner claimed.
Rather, as Appellant points outs (Appeal Br. 19) and in contrast to the
claimed invention, paragraph 47 of Srinivasan discloses using current and
voltage frequency spectrums to determine a battery’s internal impedance.
See Srinivasan ¶ 47 (“A module 812 derives an impedance 814 of battery
202 as a function of current and voltage frequency spectrums 804 and
808.”), id. at 47 (disclosing “a module 802 derives a frequency spectrum 804
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of stimulus current I based on the waveform stored locally at the computer”
and “module 806 derives a frequency spectrum 808 of sensed voltage Vac”);
id. ¶ 19 (“EIS is a well-known electrochemical technique and has been in
use since the 1940s to measure the internal impedance of electrochemical
cells.”). Although Srinivasan describes using current and voltage frequency
spectrums, the Examiner does not direct us to any express or inherent
disclosure regarding extracting amplitude and phase information from the
waveform signal, as claimed.
The Examiner also does not provide an adequate technical explanation
as to why one of ordinary skill in the art would have understood Srinivasan’s
teachings, for example, at paragraph 47, regarding using current and voltage
frequency spectrums to derive a battery’s internal impedance as expressly or
inherently disclosing the extracting amplitude and phase information from
the waveform signal limitation of the claim. The Examiner’s finding that
“both Applicant and Srinivasan utilize calculations in frequency after the
performance of a Fourier transform” (Ans. 6) does not adequately support
the rejection because, as Appellant notes (Reply Br. 6), performing
calculations using Fourier transform methods is not necessary to perform the
invention nor required by claim 1 and does not mean the calculations are
based on extracting the same information from the waveform signal. In
other words, the fact that Srinivasan discusses using Fourier transforms for
calculating certain parameters of its invention, without more, does not
establish that the reference necessarily discloses extracting amplitude and
phase information from the waveform signal, as required by the claim.
The Examiner’s findings that “Srinivasan teaches the use of
magnitude and phase to calculate an impedance” (Ans. 5) and the
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“transformed current and frequency spectrums taught by Srinivasan contain
the amplitude and phase information” (id. at 6) do not sufficiently support
anticipation by Srinivasan of the claimed step of “extracting amplitude and
phase information from the waveform signal” because the Examiner has not
adequately established that Srinivasan necessarily extracts amplitude and
phase information from the waveform signal to calculate isolation
impedance.
We, therefore, do not sustain the Examiner’s rejection of claim 1.
Because claims 2, 5, and 9 depend from claim 1 and claims 14 and 15 each
includes language similar to the “extracting amplitude and phase information
from the waveform signal” limitation of claim 1, we also do not sustain the
Examiner’s rejection of those claims for the same reasons as claim 1.
Claim 10
Claim 10 recites:
A system for determining isolation impedance, that system
comprising:
a signal source that generates an excitation signal, the
excitation signal is coupled to a high voltage system via a first
impedance;
a measuring system that measures a waveform signal at a
voltage node that is coupled to the first impedance; and
a processor that calculates an isolation impedance
between the high voltage system and a ground potential based
on the waveform signal.
Appeal Br. 24 (key disputed claim language italicized and bolded).
The Examiner determines that Srinivasan describes a system for
determining isolation impedance satisfying each limitation of claim 10 and
anticipates the claim. Final Act. 15. Regarding “a processor that calculates
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an isolation impedance between the high voltage system and a ground
potential based on the waveform signal” recitation of claim 10, the Examiner
relies principally on paragraph 32 and Figure 4 of Srinivasan for disclosing
that limitation. Id. at 15. In particular, the Examiner finds Srinivasan
teaches that “computer 224 determines an internal impedance” and “the
internal impedance is between V.sub.O and ground, as shown as
terminals 206 and 208 in Figure 4.” Id. at 15.
As part of the Examiner’s analysis, the Examiner construes the term
“isolation impedance” to mean “the impedance of the battery is ‘isolating’
the high voltage terminal of the battery (node 206) from the low voltage
terminal of the battery (208),” which the Examiner contends constitutes the
broadest reasonable interpretation. Ans. 10.
Appellant argues the Examiner’s rejection of claim 10 should be
reversed because Srinivasan does not disclose “a processor that calculates an
isolation impedance between the high voltage system and a ground potential
based on the waveform signal,” as required by the claim. Appeal Br. 20. In
particular, Appellant contends the rejection should be reversed because the
Examiner’s interpretation of the term “isolation impedance” to encompass
Srinivasan’s disclosure regarding its battery’s internal impedance is
unreasonable and inconsistent with the description provided in Appellant’s
Specification. Id. at 20–21; see also Reply Br. 8 (arguing “the internal series
impedance of battery cannot be reasonably interpreted as an isolation
impedance”).
We agree with Appellant’s argument. During prosecution, claims are
given their broadest reasonable interpretation consistent with the
specification. In re Am. Acad. of Sci. Tech. Ctr., 367 F.3d 1359, 1364 (Fed.
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Cir. 2004). The words used in a claim must be read in light of the
specification, as they would have been interpreted by one of ordinary skill in
the art at the time of the invention. Id. at 1364.
As Appellant points out (Appeal Br. 21), the Specification describes
the “isolation impedance comprises leakage resistance and total capacitance
that are coupled in parallel between the high voltage system and the
chassis.” Spec. ¶¶ 6, 35, Abstract. Based on this description, we agree with
Appellant that a person of ordinary skill in the art would not have reasonably
interpreted Srinivasan’s disclosures regarding determining a battery’s
“internal impedance” (Srinivasan ¶ 32) as disclosing “calculating an
isolation impedance between the high voltage system and a ground potential
based on the waveform signal,” as recited in the claim. We find no support
in the claims or Specification for the Examiner’s overly-broad interpretation.
The Examiner does not adequately explain how or why one of
ordinary skill in the art would have considered Srinivasan’s disclosure
regarding its battery’s internal impedance as falling within the scope of the
claimed isolation impedance, as described in Appellant’s Specification. For
example, the Examiner does not direct us to any description in Appellant’s
Specification, the prior art or any other evidence of record to establish that
the internal impedance Srinivasan discusses in paragraphs 19 and 32 is,
indeed, equivalent to or would have been reasonably considered by one of
ordinary skill in the art as corresponding to the isolation impedance recited
in the claim. The fact that the portion of Srinivasan the Examiner cites and
relies upon in the rejection and claim 10 both happen to include the word
“impedance,” without more, is insufficient to support the Examiner’s
findings and rejection in this regard.
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We, therefore, do not sustain the Examiner’s rejection of claim 10.
Because claims 11, 12, 15, 16 and 19 depend from claim 10, we also do not
sustain the Examiner’s rejection of those claims for the same reasons as
claim 10.
Accordingly, we reverse the Examiner’s rejection of claims 1, 2, 5,
9–12, 15, 16, 19 under 35 U.S.C. §§ 102(a)(1) and 102(a)(2) as anticipated
by Srinivasan.
Rejections 2, 3, and 4
The Examiner rejects claims 3, 4, 13, and 14 under § 103 as obvious
over the combination of Srinivasan and Pickerd (Rejection 2), claim 6 under
§ 103 as obvious over the combination of Srinivasan and Wolft (Rejection
3), and claims 7, 8, 17, 18, and 20 under § 103 as obvious over the
combination of Srinivasan and Janke (Rejection 4). Final Act. 17–26.
The foregoing deficiencies in the Examiner’s analysis and findings
regarding Rejection 1 and the Srinivasan reference are not remedied by the
Examiner’s findings regarding the additional references and combination of
references cited in support of the second, third, and fourth grounds of
rejection. Thus, for principally the same reasons discussed above in
connection with Rejection 1, we reverse the Examiner’s Rejections 2, 3,
and 4.

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CONCLUSION
In summary:
Claim(s)
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
1, 2, 5, 9–12,
15, 16, 19
102(a)(1) Srinivasan 1, 2, 5,
9–12, 15,
16, 19
1, 2, 5, 9–12,
15, 16, 19
102(a)(2) Srinivasan 1, 2, 5,
9–12, 15,
16, 19
3, 4, 13, 14 103 Srinivasan, Pickerd

3, 4, 13, 14
6 103 Srinivasan, Wolft

6
7, 8, 17, 18,
20
103 Srinivasan, Janke 7, 8, 17,
18, 20
Overall
Outcome
1–20

REVERSED