Ex Parte Zhang et al

Patent Trial and Appeal Board

May 12, 2016

13513992 (P.T.A.B. May. 12, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/513,992 06/05/2012
65913 7590 05/16/2016
Intellectual Property and Licensing
NXPB.V.
411 East Plumeria Drive, MS41
SAN JOSE, CA 95134
FIRST NAMED INVENTOR
Cheng Zhang
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
81413480 US04 4313
EXAMINER
JACKSON, LAKAISHA
ART UNIT PAPER NUMBER
2838
NOTIFICATION DATE DELIVERY MODE
05/16/2016 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):
ip.department.us@nxp.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Exparte CHENG ZHANG and
HANS HALBERSTADT
Appeal2014-009783
Application 13/513,992
Technology Center 2800
Before MAHSHID D. SAADAT, JOHNNY A. KUMAR, and
JON M. JURGOV AN, Administrative Patent Judges.
JURGOVAN, Administrative Patent Judge.
DECISION ON APPEAL
Appellants 1 seek review under 35 U.S.C. § 134(a) from a final
rejection of claims 28-33, 35-37, and 39. Claims 34 and 38 were indicated
as containing allowable subject matter. Claims 1-27 were canceled. We
have jurisdiction under 35 U.S.C. § 6(b ).
We affirm.2
1 Appellants identify NXP B.V. as the real party in interest. (App. Br. 1.)
2 Our Decision refers to the Specification filed June 5, 2012 ("Spec."), the
Final Office Action mailed Feb. 14, 2014 ("Final Act."), the Appeal Brief
filed May 14, 2014 ("App. Br."), the Examiner's Answer mailed Aug. 11,
2014 ("Ans."), and the Reply Brief filed Sept. 16, 2014 ("Reply Br.").
Appeal2014-009783
Application 13/513,992
STATEMENT OF THE CASE
The claims are directed to a power factor corrector with a high power
factor at low load conditions. (Spec. Title.)
Claim 28, reproduced below, is illustrative of the claimed subject
matter:
28. A circuit configured to control power delivered to a load
by an AC/DC power converter, the AC/DC power converter
configured to receive a mains alternating current (AC) voltage
as an input, the mains AC voltage having a mains voltage cycle
of an absolute voltage value varying in a cyclic manner from a
first zero to a second zero over a cycle period, the cycle period
having a first half-cycle period during which the absolute
voltage value increases from the first zero to a maximum, and a
second half-cycle period during which the absolute voltage
value decreases from the maximum to the second zero, the
circuit comprising:
a rectifier configured to receive the mains AC voltage
and produce a direct current (DC) voltage;
a switched mode power supply (SMPS) configured to
receive the DC voltage, produce an output voltage, and provide
the output voltage and a drive current to the load, the SMPS
including a control switch, being switchable between an ON
and an OFF state and only conducting during said ON state to
control the output voltage and drive current delivered to the
load;
a filter configured to receive a filter current; and
a feedback control circuit configured to drive the control
switch between the ON and OFF states, wherein the feedback
control circuit shifts the drive current relative to the mains
voltage cycle by generating a[ n] error signal based on a
difference between a reference mains current signal and a
sensed current signal at an output of the rectifier, and modifying
the drive current based on the error signal so that the reference
mains current signal and the sensed current signal have current
shapes based upon an input desired mains current shape.
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Appeal2014-009783
Application 13/513,992
REJECTIONS
Claims 28-30, 32, 35, 37, and 39 stand rejected under 35 U.S.C.
§ 102(b) based on Ng (US 7,688,041 B2; Mar. 30, 2010). (Final Act. 2-5.)
Claim 31 stands rejected under 35 U.S.C. § 103(a) based on Ng,
Smith (US 7,268,526 Bl; Sept. 11, 2007), and Hu (US 7,936,575 B2; May
3, 2011 ). (Final Act. 5---6.)
Claim 33 stands rejected under 35 U.S.C. § 103(a) based on Ng and
Yeh et al. (US 2010/0124080 Al; May 20, 2010). (Final Act. 6.)
Claim 36 stands rejected under 35 U.S.C. § 103(a) based on Ng and
Baker (US 5,594,630; Jan. 14, 1997). (Final Act. 6-7.)
ANALYSIS
§ 102(b) Rejection of Independent Claim 28
Issue 1: Does Ng disclose "modifYing the drive current based on the
. l "? error szgna. .
Appellants contend the Examiner failed to address the step of
modifying the drive current based on an error signal, and merely relied upon
inherency in Ng's power converter to disclose the disputed limitation
without providing a basis in fact or technical reasoning to support the
Examiner's finding. (App. Br. 5---6.) We are not persuaded of Examiner
error by Appellants' contention. The Examiner finds, and we agree, that Ng
explicitly discloses the disputed limitation, specifically that Ng's drive
current (i.e., the load current at VOUT) is controlled by the switch signal G,
which has an input component of error signal IERR; thus, signal G is used to
modify the drive current based on the error signal. (Final Act. 2--4; Ans.
2-3; citing Ng col. 3, 11. 31-35).
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Appeal2014-009783
Application 13/513,992
We observe that Appellants did not rebut the Examiner's findings in
response to Appellant's arguments regarding Ng's modifying the drive
current based on an error signal (see Reply Br. 2-3). Therefore, in the
absence of sufficient rebuttal evidence or argument to persuade us otherwise,
in light of the discussion above, we are not persuaded of error in the
Examiner's finding that Ng discloses modifying the drive current based on
the error signal recited in claim 28.
Issue 2: Does Ng disclose "the reference mains current signal and the
sensed current signal have current shapes based upon an input desired
mains current shape"?
Appellants contend the claimed input desired mains current shape is
not disclosed or inherent in Ng, because Ng' s comparator uses a sinusoidal
current signal that emulates a resistive load but does not use a desired mains
current shape. (App. Br. 6-7; Reply Br. 2-3.) The Examiner finds Ng's
input mains AC signal is the input desired mains current shape (Final Act.
3), and finds Ng's feedback control circuit uses the error signal IERR to
adjust the drive current (i.e., load current at VOUT) such that the sensed
current signal IFB and the reference mains current signal VSIN have current
shapes based upon the desired mains AC signal shape (Final Act. 3--4; Ans.
3; citing Ng col. 3, 11. 31-35).
In light of Appellants' disclosure that the input desired mains current
shape may be equivalent to the AC mains power source current shape (see
Spec. i-f 83), we agree with the Examiner's finding that Ng's input AC mains
signal shape discloses the claimed input desired mains current shape.
Further, under the broadest reasonable interpretation consistent with
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Appeal2014-009783
Application 13/513,992
Appellants' disclosure, we agree with the Examiner's finding that Ng's
reference and sensed current shapes are "based upon" the input desired
mains current shape, due to their dependency on the electrical characteristics
of the input AC mains current shape in Ng's AC/DC power converter circuit.
(Final Act. 3--4; Ans. 3; see In re Am. Acad. of Sci. Tech. Ctr., 367 F.3d
1359, 1369 (Fed. Cir. 2004).)
Therefore, we sustain the 35 U.S.C. § 102(b) rejection of claim 28.
§ 102(b) Rejection of Dependent Claim 29
Issue: Does Ng disclose a first scaling unit configured to receive both
the "error signal and a power level signal based on the output voltage"?
Appellants contend Ng' s RAMP signal does not disclose a power
level signal, because RAMP is produced by a ramp generator and is not
based on the output voltage. (App. Br. 8.) Further, Appellants argue the
ramp generator has only a single input and cannot be the same as the
claimed scaling unit that receives both the error signal and the power level
signal. (Reply Br. 3.) Appellants' contentions are not persuasive of error.
The Examiner finds, and we agree, that the broadest reasonable
interpretation of "based on the output voltage" that is consistent with
Appellants' disclosure encompasses any indirect connection between the
power level signal (i.e., RAMP signal) and the output voltage VOUT. (Ans.
4; see In re Am. A cad. of Sci. Tech. Ctr., supra.) Thus, we agree with the
Examiner's finding that Ng's power level signal RAMP, which has VOUT
as an indirect feedback component, is received with error signal IERR at
Ng's comparator in order to produce control signal G. (Final Act. 4; Ans.
4.)
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Application 13/513,992
Therefore, we sustain the 35 U.S.C. § 102(b) rejection of claim 29.
§ 103(a) Rejections of Claims 31, 33, and 36
Appellants contend the Examiner failed to provide articulated
reasoning to support the obviousness rejections of claims 31, 33, and 36.
(App. Br. 13). We are not persuaded of Examiner error in the rejections,
because the Examiner has provided articulated reasoning with some rational
underpinning to support the legal conclusion of obviousness for each
rejection, specifically the proffered combinations result in a power converter
that operates more efficiently and is prevented from system overload. (Final
Act. 5-7; see KSR Int'! Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007)
(quoting In re Kahn, 441F.3d977, 988 (Fed. Cir. 2006)).)
Accordingly, we sustain the 35 U.S.C. § 103(a) rejections of claim 31,
33, and 36.
Remaining Claims
Appellants present no separate arguments for claims 30, 32, 35, 37,
and 39 (see App. Br. 9). We therefore sustain their rejection for the reasons
stated with respect to independent claim 28.
DECISION
The Examiner's rejections of claims 28-33, 35-37, and 39 are
affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(l )(iv).
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Appeal2014-009783
Application 13/513,992
AFFIRMED
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