Allegro MicroSystems, LLC

Patent Trials and Appeals Board

Aug 25, 2020

2019005737 (P.T.A.B. Aug. 25, 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.
15/374,154 12/09/2016 Yisong Lu ALLEG-620PUS 4632
22494 7590 08/25/2020
DALY, CROWLEY, MOFFORD & DURKEE, LLP
SUITE 201B
ONE UNIVERSITY AVENUE
WESTWOOD, MA 02090
EXAMINER
DUDA, RINA I
ART UNIT PAPER NUMBER
2846
NOTIFICATION DATE DELIVERY MODE
08/25/2020 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):
amk@dc-m.com
docketing@dc-m.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte YISONG LU and LYNDON AMBRUSON
Appeal 2019-005737
Application 15/374,154
Technology Center 2800
Before KAREN M. HASTINGS, JAMES C. HOUSEL, and
LILAN REN, Administrative Patent Judges.
HOUSEL, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1–32.2 We have jurisdiction under
35 U.S.C. § 6(b).

1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R.
§ 1.42. Appellant identifies the real party in interest as Allegro
MicroSystems, LLC. Appeal Brief (“Appeal Br.”) filed October 25, 2018, at
2.
2 Appellant only lists claims 1–4, 8, 9, 11–17, 19, 23–27, and 29 under the
status of the claims, but asserts that claims 1–32 are patentable in the
conclusion. Compare Appeal Br. 2 and 11.
Appeal 2019-005737
Application 15/374,154

2
We REVERSE.3
CLAIMED SUBJECT MATTER
The invention relates to methods and apparatus for a brushless direct
current (“BLDC”) electric motor controller “including a magnetic field
sensing element having an output that is processed to generate polarity and
amplitude signals for regulating an output current to reduce acoustic noise
during startup in comparison with conventional systems.” Spec. 2:2–5.
Claim 1, reproduced below from the Claims Appendix to the Appeal
Brief, is illustrative of the claimed subject matter:
1. A method for three-phase motor startup, comprising:
receiving differential outputs from a magnetic field
sensing element;
generating a polarity signal from the differential outputs;
receiving the differential outputs and generating an
amplitude signal;
generating a motor direction drive signal from the
polarity signal; and
generating sinusoidal motor drive signals during the
motor startup from a measured motor current signal and the
amplitude signal, wherein the motor drive signals drive the
motor in a direction corresponding to the motor direction drive
signal.

3 This Decision also cites to the Specification (“Spec.”) filed December 9,
2016, the Final Office Action (“Final Act.”) dated June 27, 2018, the
Examiner’s Answer (“Ans.”) dated May 15, 2019, and the Reply Brief
(“Reply Br.”) filed July 11, 2019.
Appeal 2019-005737
Application 15/374,154

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Independent claim 12 recites a motor controller system having a
control module configured to receive polarity and amplitude
information generated from differential outputs from magnetic field
sensing element and to generate a motor driving direction signal from
the polarity information and an amplitude control signal from the
amplitude information and measured motor current information.
Independent claim 23 recites a control means for performing the same
functions as the control module of claim 12.
REFERENCES
The Examiner relies on the following prior art:
Name Reference Date
Brannen US 9,083,273 B2 July 14, 2015
Ng US 2014/0055064 A1 Feb. 27, 2014

REJECTIONS
The Examiner maintains, and Appellant requests our review of, the
following rejections:
A. Claims 1–4, 8, 9, 11–17, 19, 23–27, and 29 under 35 U.S.C.
§ 102(a)(1) as anticipated by Brannen; and
B. Claims 5–7, 10, 18, 20–22, 28, and 30–32 under 35 U.S.C.
§ 103 as unpatentable over Brannen in view of Ng.
OPINION
We review the appealed rejections for error based upon the issues
Appellant identifies, and in light of the arguments and evidence produced
thereon. Ex parte Frye, 94 USPQ2d 1072, 1075 (BPAI 2010) (precedential)
(cited with approval in In re Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011)
Appeal 2019-005737
Application 15/374,154

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(“[I]t has long been the Board’s practice to require an applicant to identify
the alleged error in the examiner’s rejections.”). After considering the record
before us, we are persuaded of reversible error in the pending rejections.
Anticipation is established when a single prior art reference discloses
all features of the claimed invention. ClearValue, Inc. v. Pearl River
Polymers, Inc., 668 F.3d 1340, 1344 (Fed. Cir. 2012); Celeritas Techs., Ltd.
v. Rockwell Int’l Corp., 150 F.3d 1354, 1361 (Fed. Cir. 1998) (A claim is
anticipated only where “each and every limitation is found either expressly
or inherently in a single prior art reference.”); In re Spada, 911 F.2d 705,
708 (Fed. Cir. 1990); Verdegaal Bros., Inc. v. Union Oil Co. of Cal., 814
F.2d 628, 631 (Fed. Cir. 1987) (“A claim is anticipated only if each and
every element as set forth in the claim is found, either expressly or
inherently described, in a single prior art reference.”).
The Examiner finds that Brannen teaches the method of claim 1, the
motor controller of claim 12, and the motor controller system of claim 23.
Final Act. 3–5. In particular, the Examiner finds that Brannen teaches,
among other things, a motor controller generating a polarity signal and an
amplitude signal from the differential outputs from a magnetic field sensing
element. Id. at 3. In support of this finding, the Examiner notes that Brannen
teaches that the differential outputs are nearly sinusoidal with an amplitude
of a few hundred millivolts, which is amplified and interpreted by a motor
control integrated circuit (“IC”). Ans. 4; Brannen 4:6–11. In addition, the
Examiner notes that Brannen teaches that a commutation logic decodes the
amplified polarity information in order to determine which of the pre-driver
H-Bridge driver switches will be turned on, and ultimately the direction of
current flow in the stator windings. Ans. 4; Brannen 4:17–21.
Appeal 2019-005737
Application 15/374,154

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Appellant argues that Brannen only generates a polarity signal from
the sensing element’s differential outputs and fails to teach generating an
amplitude signal from these outputs. Appeal Br. 5. Appellant asserts that
Brannen, Figure 4, shows the amplified polarity signal generated from the
sensor’s differential outputs is a logic signal consisting of only 0’s and 1’s.
Id. at 5–6. Moreover, Appellant asserts that Brannen’s differential outputs
are received by a single amplifier which is only capable of generating a
single signal, i.e., a polarity signal, whereas Appellant’s differential outputs
are received by amplifier 202 for generating the polarity signal and rectifier
210 for generating the amplitude signal. Id. at 6–7.
Appellant’s argument is persuasive of reversible error. As Appellant
argues, Brannen, Figure 4, clearly shows the output of the amplifier
receiving the sensor differential outputs is a polarity signal consisting of
only 0’s and 1’s, i.e., only zero volts representing a negative voltage of the
sensor output and a setpoint voltage representing a positive voltage of the
sensor output. Notably, the Examiner fails to respond to Appellant’s
argument in this regard. Further, as Appellant asserts, Brannen’s Hall sensor
differential outputs are sent only to the Hall Amplifier 108. Although, as the
Examiner correctly finds, Appellant’s claims (other than claim 9) do not
recite a second electronic element, e.g., a rectifier, for producing the
amplitude signal, the claims require the generation of both a polarity signal
and an amplitude signal from the sensor’s differential outputs.
Brannen’s amplifier is only capable of producing the single polarity
signal shown in Figure 4. This conclusion is consistent with Brannen’s
disclosure in column 4, lines 4–21. Brannen’s sensor outputs are indeed
sinusoidal having an amplitude of a few hundred millivolts. Brannen 4:8–10.
Appeal 2019-005737
Application 15/374,154

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However, Brannen amplifies this “small differential signal” by the Hall
Amplifier and provides a motor control IC to interpret the amplified output
signal as north and south rotor positions, i.e., polarity information only. Id.
at 4:10–12. Brannen teaches that this amplified signal “is pinned out of the
IC as an open drain output on the Tach (tachometer) pin” whose “Tach
signal toggles between a logical one and zero.” Id. at 4:12–15. In addition,
Brannen’s Commutation Logic 112 decodes the polarity information from
the amplified signal to ultimately determine the direction of current flow of
the stator windings, i.e., the motor direction drive signal. Id. at 4:17–21. The
Examiner fails to direct our attention to any teaching in Brannen that an
amplitude signal, distinct from the polarity signal, is generated from the
sensor’s differential outputs, much less generating sinusoidal motor drive
signals from this amplitude signal and a motor current signal or information,
nor do we find any.
Accordingly, we do not sustain the Examiner’s anticipation rejection
of claims 1–4, 8, 9, 11–17, 19, 23–27, and 29 by Brannen.
The Examiner additionally relies on Ng in rejecting claims 5–7, 10,
18, 20–22, 28, and 30–32 as unpatentable under 35 U.S.C. § 103. However,
the Examiner does not rely on Ng to remedy the deficiencies in Brannen
discussed above. As such, the Examiner’s obviousness rejection lacks
sufficient factual underpinning. In re Kahn, 441 F.3d 977, 988 (Fed. Cir.
2006) (“[R]ejections on obviousness grounds cannot be sustained by mere
conclusory statements; instead, there must be some articulated reasoning
with some rational underpinning to support the legal conclusion of
obviousness.” quoted with approval in KSR Int’l Co. v. Teleflex Inc., 550
U.S. 398, 418 (2007)).
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Application 15/374,154

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Accordingly, we likewise do not sustain the Examiner’s obviousness
rejection of claims 5–7, 10, 18, 20–22, 28, and 30–32 over Brannen and Ng.
CONCLUSION
Upon consideration of the record and for the reasons set forth above
and in the Appeal and Reply Briefs, the Examiner’s decision to reject claims
1–32 is reversed.
More specifically,
the rejection of claims 1–4, 8, 9, 11–17, 19, 23–27, and 29 under 35
U.S.C. § 102(a)(1) as anticipated by Brannen is reversed; and
the rejection of claims 5–7, 10, 18, 20–22, 28, and 30–32 under 35
U.S.C. § 103 as unpatentable over Brannen in view of Ng is reversed.
DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
1–4, 8, 9,
11–17, 19,
23–27, 29
102(a)(1) Brannen 1–4, 8, 9,
11–17, 19,
23–27, 29
5–7, 10, 18,
20–22, 28,
30–32
103 Brannen, Ng 5–7, 10, 18,
20–22, 28,
30–32
Overall
Outcome
1–32

REVERSED