Darryl Tschirhart et al.

Patent Trials and Appeals Board

Jun 29, 2020

2018008292 (P.T.A.B. Jun. 29, 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.
14/726,009 05/29/2015 Darryl Tschirhart 1012-1047 /
2015P50191 US
1112
57579 7590 06/29/2020
MURPHY, BILAK & HOMILLER/INFINEON TECHNOLOGIES
1255 CRESCENT GREEN
SUITE 200
CARY, NC 27518
EXAMINER
AHMAD, KHAJA
ART UNIT PAPER NUMBER
2813
NOTIFICATION DATE DELIVERY MODE
06/29/2020 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):
official@mbhiplaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
_________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
__________

Ex parte DARRYL TSCHIRHART, BENJAMIM TANG, and
EMIL TODOROV
__________

Appeal 2018-008292
Application 14/726,009
Technology Center 2800
___________

Before ADRIENE LEPIANE HANLON, ROMULO H. DELMENDO, and
JAMES C. HOUSEL, Administrative Patent Judges.

HANLON, Administrative Patent Judge.

DECISION ON APPEAL

A. STATEMENT OF THE CASE
The Appellant1 filed an appeal under 35 U.S.C. § 134(a) from an Examiner’s
decision finally rejecting claims 1, 2, 6, 8–15, 19–22, 24, 25, and 27. Claims 3, 5,
16–18, and 26 are also pending but have been withdrawn from consideration. We
have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.

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 Infineon Technologies
Austria AG. Appeal Brief dated March 15, 2018 (“App. Br.”), at 2.
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Application 14/726,009

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The claims on appeal are directed to a DC-DC converter. Claim 1, the sole
independent claim on appeal, is reproduced below from the Claims Appendix to
the Appeal Brief. The limitation at issue is italicized.
1. A DC-DC converter, comprising:
a substrate having opposing first and second sides;
a first discrete power stage transistor die attached to the first
side of the substrate and comprising a high-side power transistor;
a second discrete power stage transistor die attached to the first
side of the substrate and comprising a low-side power transistor
electrically connected to the high-side power transistor to form an
output phase of the DC-DC converter; and
an inductor attached to the first side of the substrate so as to
electrically connect the output phase to a metal output trace on the
substrate, the inductor at least partly covering at least one of the first
and the second discrete power stage transistor dies,
wherein each discrete power stage transistor die that is at least
partly covered by the inductor comprises a plurality of pins that are
not covered by the inductor.
App. Br. 14.
The claims on appeal stand rejected as follows:
(1) claims 1, 2, 6, 8, 10–15, 19, 21, 22, 24, and 25 under 35 U.S.C. § 103
as unpatentable over Yin et al.2 in view of Ishii et al.;3
(2) claims 9 and 20 under 35 U.S.C. § 103 as unpatentable over Yin in
view of Ishii, and further in view of Shimada et al.;4 and
(3) claim 27 under 35 U.S.C. § 103 as unpatentable over Yin in view of
Ishii, and further in view of Jones et al.5

2 US 2011/0228507 A1, published September 22, 2011 (“Yin”).
3 US 2016/0164417 A1, published June 9, 2016 (“Ishii”).
4 US 2009/0147541 A1, published June 11, 2009 (“Shimada”).
5 US 2014/0239472 A1, published August 28, 2014 (“Jones”).
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Application 14/726,009

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B. DISCUSSION
The Examiner finds Yin discloses a DC-DC converter comprising, inter alia,
first and second discrete power stage transistor dies 16 attached to a first side of a
substrate and an inductor “at least partly covering at least one of the first and the
second discrete power stage transistor dies.” Final Act. 3.6 Yin Figure 4, for
example, shows inductor 68 fully covering first and second transistors 16. The
Examiner concludes that “fully covered meets the limitation of at least partly
covered” recited in claim 1. Final Act. 5.
The Examiner finds Yin “does not teach wherein each discrete power stage
transistor die that is at least partly covered by the inductor comprises a plurality of
pins that are not covered by the inductor” as recited in claim 1. Final Act. 3.
The Examiner finds Ishii discloses a DC-DC converter comprising, inter
alia, switching transistors and an inductor “wherein some pins (wires coming out
of pad from 32) of the transistor (32) are partly covered by the inductor (40).”
Final Act. 4. In that regard, Ishii Figure 2A shows that a segment of each of the
wires connecting transistors 31, 32 to controller IC chip 33 is not covered by
inductor 40. The Examiner finds that the wires depicted in Ishii Figure 2A can be
considered pins based on the broadest reasonable interpretation of the term “pin.”
Final Act. 12.
Ishii discloses that “[t]he controller IC chip 33 is connected, by wire
bonding, to the gates of the high-side switching transistor 31 and the low-side
switching transistor 32.” Ishii ¶ 43 (emphasis added); see also App. Br. 6 (citing
Ishii ¶ 43). The Appellant argues that “Ishii does not disclose or suggest . . . that
any ‘wire bonding’ is a pin.” App. Br. 6.

6 Final Office Action dated October 11, 2017.
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Application 14/726,009

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In response, the Examiner finds that the Appellant’s “specification does not
provide any specific definition of the claimed term ‘PIN.’”7 Ans. 4.8 Therefore,
the Examiner considers the term “‘PIN’” to be
a conductive wire that is used for connecting input or output terminals
of [a] semiconductor device to external components on a broadest
reasonable interpretation. Thus, it is a reasonable interpretation to call
the wires (bonding wires) of Ishii (Figures 1/2) connecting the
transistors (31/32) with external device (33) as “pins” of the
transistors.
Ans. 4.
The Examiner relies on paragraph 53 of Ananiev,9 paragraph 63 of Han et
al.,10 and paragraph 29 of Truax et al.11 to establish that “wires and pins are used
interchangeably in prior arts.” Final Act. 12; see also Advisory Act. 212 (relying
on Ananiev, Han, and Truax to show that a pin and a bonding wire are used
interchangeably); Ans. 5 (explaining that Ananiev, Han, and Truax were used to
support the interpretation of the term “pin” as a conductive wire such as Ishii’s
bonding wire).
The Appellant argues that the additional art relied on by the Examiner “does
not show that ‘wire bonding’ and ‘pins’ are equivalent” but rather “describes such
elements as alternatives to each other.” App. Br. 8. The Appellant’s argument is
persuasive of reversible error.

7 Referring to Figure 4B, the Appellant discloses that “the pins 326 of each discrete
high-side transistor die 306, 308 . . . remain uncovered by the inductor 310 [and]
can be visually inspected without interference from the inductor 310.” Spec. ¶ 28.
8 Examiner’s Answer dated June 15, 2018.
9 US 2015/0194374 A1, published July 9, 2015 (“Ananiev”).
10 US 2015/0311655 A1, published October 29, 2015 (“Han”).
11 US 2016/0163631 A1, published June 9, 2016 (“Truax”).
12 Advisory Action dated January 5, 2018.
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Application 14/726,009

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Turning to the prior art relied on by the Examiner, paragraph 53 of Ananiev
states that “each of the terminal pins 122 of the package 120 is designed here as a
curved wire-shaped copper structure” (emphasis added). The Appellant argues
that such wording suggests that the terminal pins 122 are not necessarily wires
because “[o]ne would typically not describe a wire as ‘wire-shaped.’” App. Br. 9.
Moreover, the Appellant directs our attention to paragraphs 28 and 54 of
Ananiev which describe “pins” and “bonding wires” as different elements. App.
Br. 9. In that regard, Ananiev discloses that “electronic chip(s) may be
electronically coupled with the terminal pins through bonding wires.” Ananiev
¶ 28 (emphasis added). Likewise, Ananiev describes “terminal pins 122” and
“bonding wires 152” (Ananiev ¶ 54) and Ananiev Figure 1 depicts pins 122 and
bonding wires 152 as different elements.
Paragraph 63 of Han states that “the terms ‘lands’, ‘contact lands’, and like
may refer to any type of electrical connection such as a lead, wire, pin, and/or any
other like device that can enable an electrical connection.” The Appellant argues
that Han, in paragraph 63, merely “lists leads, wires, pins, etc. as alternatives for
providing an electrical connection” and “describes ‘contact pins’ 113 and ‘wirings’
115 as different elements.” App. Br. 10 (emphasis omitted); see also Han Fig. 1
(depicting pins 113 and wirings 115 as different elements).
Finally, paragraph 29 of Truax states that “input/output pins 150 can
comprise metal wires (e.g., coated copper wires, tinned copper wires or any other
suitable electrically conductive wire)” and refers to pins 150 as “leads or external
connectors.” The Appellant argues that Truax does not equate wiring bonding with
pins 150, but rather describes pins 150 and bonding wires 191 as different
elements. App. Br. 10–11. Indeed, Truax discloses that pin 150 can be electrically
connected to wire bond pad 141 and wire bond pad 141, in turn, can be wire
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Application 14/726,009

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bonded via wire 191 to chip 210. Truax ¶¶ 29, 32; see also Truax Fig. 3A
(depicting pin 150 and wire 191 as different elements).
Based on the foregoing, a preponderance of the evidence of record
establishes that one of ordinary skill in the art would not have understood that the
term “pins,” as recited in claim 1, and the term “wire bonding,” as disclosed in
Ishii, refer to the same structural element. Therefore, the Examiner has failed to
show that the DC-DC converter recited in claim 1 is rendered obvious by the
combination of Yin and Ishii.
The Examiner has also failed to show that either Shimada or Jones cures the
deficiency in the combination of Yin and Ishii identified above. Notably, the
Examiner relies on Jones to show that a plurality of pins (318) of two MOSFETs
(306, 308) are not covered by a semiconductor die (302). Final Act. 11. However,
the Appellant argues that the semiconductor die (302) is not an inductor as
claimed, and for that reason, Jones does not disclose or suggest the claimed feature
missing from Yin (i.e., a transistor die comprising a plurality of pins that are not
covered by an inductor). App. Br. 12.
In response, the Examiner concludes that it would have been obvious to one
of ordinary skill in the art “to use an arrangement in the DC-DC converter of
YIN . . . so that a plurality of pins of the high-side power transistor die are not
covered by the inductor, wherein . . . such an arrangement provides a good heat
dissipation of the power transistors.” Ans. 8–9.
The Appellant argues that the Examiner “does not provide a citation
regarding this being a goal within the cited art, or explain[] why such a goal would
be obvious to one skilled in the art.” Reply Br. 6.13 Indeed, the Examiner does not

13 Reply Brief dated August 15, 2018.
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direct us to any evidence or provide any technical reasoning showing that, at the
time of the Appellant’s invention, one of ordinary skill in the art would have
known that not covering the pins of Yin’s transistors 16 with an inductor, as
claimed, would provide good heat dissipation of transistors 16. See In re Kahn,
441 F.3d 977, 988 (Fed. Cir. 2006) (“rejections 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”).
For the reasons set forth above, the obviousness rejections on appeal are not
sustained.
C. CONCLUSION
The Examiner’s decision is reversed.
In summary:

Claims
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
1, 2, 6, 8, 10–
15, 19, 21,
22, 24, 25
103 Yin, Ishii 1, 2, 6, 8, 10–
15, 19, 21,
22, 24, 25
9, 20 103 Yin, Ishii, Shimada 9, 20
27 103 Yin, Ishii, Jones 27
Overall
Outcome
1, 2, 6, 8–15,
19–22, 24,
25, 27

REVERSED