NXP B.V.

Patent Trials and Appeals Board

Apr 21, 2021

2020002654 (P.T.A.B. Apr. 21, 2021)

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.
14/697,860 04/28/2015 Gian Hoogzaad 81635500US04 5435
65913 7590 04/21/2021
Intellectual Property and Licensing
NXP B.V.
350 Holger Way
SAN JOSE, CA 95134
EXAMINER
O TOOLE, COLLEEN J
ART UNIT PAPER NUMBER
2849
NOTIFICATION DATE DELIVERY MODE
04/21/2021 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
Ex parte GIAN HOOGZAAD and JOZEF BERGERVOET
Appeal 2020-002654
Application 14/697,860
Technology Center 2800
Before KAREN M. HASTINGS, DEBRA L. DENNETT, and
SHELDON M. McGEE, Administrative Patent Judges.
HASTINGS, 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 and 3–21. See Final Act. 1. We have
jurisdiction under 35 U.S.C. § 6(b).
We reverse.

1 We use the term “Appellant” to refer to “applicant” as defined in 37 C.F.R.
§ 1.42. Appellant identifies the real party in interest of record in this
application as NXP Semiconductors. Appeal Br. 2.
Appeal 2020-002654
Application 14/697,860

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CLAIMED SUBJECT MATTER
The claims are directed to a RF switch circuit. Claims 1 and 16,
reproduced below, are illustrative of the claimed subject matter:
1. A RF switching circuit for coupling an antenna to a RF circuit,
the RF switching circuit having a first mode of operation and a
second mode of operation and comprising:
a switch arranged to switchably couple an RF signal input
to an RF signal output, the switch comprising a first transistor
having a first terminal, a second terminal, and a control terminal;
a controller circuit coupled to a bias swapping circuit and
the control terminal and operable to switch the RF switching
circuit between the first mode of operation and the second mode
of operation by switching a gate voltage applied to the control
terminal between a first gate voltage value and a second gate
voltage value, the first mode of operation including an RF
transmit mode and the second mode of operation including an RF
receive mode;
the bias swapping circuit having a bias voltage output
coupled to the first terminal and the second terminal; and
wherein the bias swapping circuit is coupled to an output
of the controller circuit and is operable to switch the bias voltage
output between a first bias voltage value and a second bias
voltage value in response to a change in the mode of operation
of the RF switching circuit from the first mode of operation to
the second mode of operation, and is operable to switch the bias
voltage output to a third bias voltage value in response to a
change in a temperature associated with the switch, or a change
in a voltage or current level of the RF signal input as received by
the RF switching circuit from a power circuit during the second
mode of operation.
16. An RF switching circuit for coupling an antenna to a RF
circuit, the RF switching circuit having a first mode of
operation and a second mode of operation and comprising:
a switch arranged to switchably couple a RF signal input
to a RF signal output, the switch comprising a first transistor
Appeal 2020-002654
Application 14/697,860

3
having a first terminal, a second terminal, and a control
terminal;
a bias swapping circuit having a bias voltage output
coupled to the first terminal and the second terminal;
a RF signal power detector coupled to the bias swapping
circuit and configured to detect a signal strength of the RF
signal input; and
wherein the bias swapping circuit is operable to vary the
bias voltage output between at least three bias voltage values
according to the signal strength of the RF signal input and a
change in the mode of operation of the RF switching circuit.
REFERENCES
The prior art relied upon by the Examiner is:
Name Reference Date
Wen US 6,502,047 B1 Dec. 31, 2002
Struble US 2004/0235549 A1 Nov. 25, 2004
Chu US 2009/0291645 A1 Nov. 26, 2009
Toda US 7,710,189 B2 May 4, 2010
REJECTIONS
Claims 1, 3, 4, 6, 9, 10, 12–17, and 19–212 are rejected under 35
U.S.C. § 103 as being unpatentable over Toda and Chu. Final Act. 2–6.
Claims 5 and 18 are rejected under 35 U.S.C. § 103 as being
unpatentable over Toda, Chu, and Wen. Final Act. 6–7.
Claims 7, 8, and 11 are rejected under 35 U.S.C. § 103 as being
unpatentable over Toda, Chu, and Struble. Final Act. 7–8.

2 It is harmless error that the Examiner did not include claims 19–21 in the
statement of the rejection (Final Act. 2), as these claims are addressed in the
rejction (Final Act. 5, 6).
Appeal 2020-002654
Application 14/697,860

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Claim(s) Rejected 35 U.S.C. § Reference(s)/Basis
1, 3, 4, 6, 9, 10,
12–17, 19–21
103 Toda, Chu
5, 18 103 Toda, Chu, Wen
7, 8, 11 103 Toda, Chu, Struble

OPINION
The Examiner bears the initial burden of presenting a prima facie case
of obviousness. In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992).
“[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.” In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006), quoted with
approval in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007).
Upon consideration of the evidence of record and each of Appellant’s
contentions as set forth in the Appeal Brief, as well as the Reply Brief, we
conclude that the preponderance of the evidence supports Appellant’s
position that the Examiner has not met the burden in this case for
substantially the same reasons as set forth by Appellant in the Briefs.
Accordingly, we reverse the Examiner’s § 103 rejections of all the claims on
appeal.
We add the following primarily for emphasis.
Specifically, a preponderance of the evidence supports Appellant’s
position that the proposed modification of Toda to modify its controlling of
on/off states of a transmitter circuit based on the teachings of Chu would be
based on undue speculation and an improper hindsight reconstruction for the
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Application 14/697,860

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reasons discussed by Appellant in the Briefs (Appeal Br. 5−6; Reply Br. 2–
8).
A preponderance of the evidence supports Appellant’s position that
modifying Toda in view of Chu fails to arrive at three different bias voltages
being applied to both the source and drain of the same transistor while
maintaining Toda’s original purpose of controlling on/off states of a
transmitter circuit. More specifically, Appellant argues that neither Toda
nor Chu teach applying a third bias voltage to both the source and drain
terminals of the same transistor (Appeal Br. 5–6; Reply Br. 3). It should be
noted that the claimed first terminal and claimed second terminal recited in
independent claims 1 and 16 are commonly referred to as source and drain,
or drain and source, respectively. This interchangeability of terms is
consistent with Appellant’s Specification which describes the transistor 10
of Appellant’s representative Figure 4 (Spec. 8:7–11).
In response, the Examiner contends that Chu teaches a third bias
voltage value being coupled to the source and drain of a single transistor
(Ans. 4). However, the third bias voltage value in Chu is not taught as being
coupled to the source and drain of a single transistor as required by the
claims, but rather the source and drain of two different transistors, M1 and
M2 (Appeal Br. 5–6; Reply Br. 3).
In response, the Examiner contends that the combined circuit of Toda
and Chu results in all three bias voltage values being applied across the
source and drain terminals of a single transistor structure (Ans. 4–5).
Appellant responds that such a modification to Toda would result in no
effective change to its circuit unless the incorporation of the Vdb bias
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Application 14/697,860

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voltage value of Chu’s Figure 3 is implemented to override Toda’s originally
intended on/off voltage bias values (Reply Br. 2).
The Examiner’s position is insufficient because the Examiner has not
provided sufficient evidence as to how modifying Toda by incorporating
Chu’s three bias voltage values would result in maintaining both the
originally intended controlling of on/off states of Toda while successfully
incorporating the transmit and receive functionality of Chu.
The fact finder must be aware “of the distortion caused by hindsight
bias and must be cautious of arguments reliant upon ex post reasoning.”
KSR, 550 U.S. at 421 (citing Graham v. John Deere Co., 383 U.S. 1, 36
(1966) (warning against a “temptation to read into the prior art the teachings
of the invention in issue”)).
The Examiner has not adequately explained why the skilled artisan’s
knowledge or inferences and creativity would have supported the
obviousness determination based on the teachings of the applied references
without undue speculation and/or an improper hindsight reconstruction of
Toda’s controlling of on/off states.
Accordingly, we reverse the § 103 rejections of the claims which all
rely upon an impermissible hindsight reconstruction of the controlling of
on/off states described in Toda based on Chu.
CONCLUSION
The Examiner’s rejections are reversed.
Appeal 2020-002654
Application 14/697,860

7
DECISION SUMMARY
Claim(s)
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
1, 3, 4,
6, 9, 10,
12–17,
19–21
103 Toda, Chu 1, 3, 4,
6, 9, 10,
12–17,
19–21
5, 18 103 Toda, Chu, Wen 5, 18
7, 8, 11 103 Toda, Chu, Struble 7, 8, 11
Overall
Outcome
1, 3–21

REVERSED