UNITED STATES PATENT AND TRADEMARK OFFICE
`____________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________
`
`SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC d/b/a
`ON SEMICONDUCTOR
`Petitioner
`
`v.
`
`POWER INTEGRATIONS, INC.
`Patent Owner
`____________
`
`Case No. Unassigned
`Patent 7,834,605
`____________
`
`
`PETITION FOR INTER PARTES REVIEW OF CLAIMS 1, 2, 5, AND 9 OF U.S.
`PATENT NO. 7,834,605
`
`
`
`
`
`
`____________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________
`
`SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC d/b/a
`ON SEMICONDUCTOR
`Petitioner
`
`v.
`
`POWER INTEGRATIONS, INC.
`Patent Owner
`____________
`
`Case No. Unassigned
`Patent 7,834,605
`____________
`
`
`PETITION FOR INTER PARTES REVIEW OF CLAIMS 1, 2, 5, AND 9 OF U.S.
`PATENT NO. 7,834,605
`
`
`
`
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`TABLE OF CONTENTS
`
`I.
`
`INTRODUCTION ........................................................................................... 1
`
`II. MANDATORY NOTICES, STANDING, AND FEES .................................. 1
`
`A. Mandatory Notices ................................................................................ 1
`
`B.
`
`C.
`
`Certification of Grounds for Standing ................................................... 3
`
`Fees ........................................................................................................ 3
`
`III. OVERVIEW OF THE ’605 PATENT ............................................................ 3
`
`A.
`
`B.
`
`C.
`
`Background of the Technology ............................................................. 4
`
`Subject Matter of the ’605 Patent .......................................................... 8
`
`The History of the ’605 Patent ............................................................ 13
`
`IV. SUMMARY OF PRIOR ART ....................................................................... 16
`
`A.
`
`de Sartre ............................................................................................... 16
`
`V.
`
`CLAIM CONSTRUCTION .......................................................................... 21
`
`VI. THERE IS A REASONABLE LIKELIHOOD THAT THE CHALLENGED
`CLAIMS ARE UNPATENTABLE .............................................................. 21
`
`A. Ground 1: de Sartre Anticipates Claims 1, 2, 5, and 9 Under 35 U.S.C.
`§ 102 .................................................................................................... 21
`
`VII. CONCLUSION .............................................................................................. 37
`
`
`
`
`
`i
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`LIST OF EXHIBITS
`
`1001
`
`1002
`
`1003
`
`1004
`
`1005
`
`1006
`
`1007
`
`1008
`
`1009
`
`1010
`
`U.S. Patent No. 7,834,605 to Balakrishnan et al. (“the ’605 Patent”)
`
`U.S. Patent No. 7,110,270 to Balakrishnan et al. (“the ’270 Patent”)
`
`Expert Declaration of Douglas Holberg
`
`CV of Douglas Holberg
`
`U.S. Patent No. 4,692,853 to de Sartre et al. (“de Sartre”)
`
`Power Integrations, Inc. v. Fairchild Semi. Int’l Inc., No. 1:08-cv-
`00309, Original Complaint (D. Del. May 23, 2008) (Dkt. 1)
`
`Power Integrations, Inc. v. Fairchild Semi. Int’l Inc., No. 1:08-cv-
`00309, Memorandum Opinion (D. Del. May 23, 2008) (Dkt. 731)
`
`U.S. Patent No. 4,763,238 by Maige (“Maige”)
`
`Power Integrations, Inc. v. Fairchild Semi. Int’l Inc., No. 1:08-cv-
`00309, Amended Complaint (D. Del. May 23, 2008) (Dkt. 401)
`
`Power Integrations, Inc. v. Fairchild Semi. Int’l Inc., No. 1:08-cv-
`00309, Order (D. Del. May 23, 2008) (Dkt. 682)
`
`
`
`ii
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`I. INTRODUCTION
`
`Semiconductor Components Industries, LLC d/b/a ON Semiconductor (“ON
`
`Semiconductor” or “Petitioner”) requests inter partes review (“IPR”) under 35
`
`U.S.C. §§ 311–319 and 37 C.F.R. § 42.100 et seq. of claims 1, 2, 5, and 9 of U.S.
`
`Patent No. 7,834,605 (“’605 Patent”).
`
`Petitioner asserts that there is a reasonable likelihood that the challenged
`
`claims are unpatentable and requests review of, and cancellation of, the challenged
`
`claims under 35 U.S.C. § 102.
`
`II. MANDATORY NOTICES, STANDING, AND FEES
`
`A. Mandatory Notices
`
`Real Party in Interest: The real parties in interest are: (i) ON Semiconductor
`
`Corporation, (ii) Semiconductor Components Industries, LLC, doing business as
`
`ON Semiconductor, and (iii) Falcon Operations Sub, Inc.
`
`On November 18, 2015, ON Semiconductor Corporation, Falcon Operations
`
`Sub, Inc., and Fairchild Semiconductor International, Inc. (“Fairchild”) entered
`
`into an Agreement and Plan of Merger, which calls for Falcon Operations Sub, Inc.
`
`to be merged with and into Fairchild, with Fairchild surviving as a wholly-owned
`
`subsidiary of ON Semiconductor Corporation. The proposed merger has not yet
`
`closed. All of the requirements and closing conditions of the Agreement and Plan
`
`of Merger have not been satisfied, and it is uncertain when or whether the merger
`
`
`
`1
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`will close. Fairchild has had no role in the decision to file this Petition, the content
`
`of this Petition, or the preparation of this Petition. Fairchild did not contribute in
`
`any manner to the funding for this Petition. Fairchild is not a real party in interest
`
`or a privy of any petitioner. The real parties in interest do not control and have not
`
`controlled any litigation between any affiliate of Fairchild and Power Integrations,
`
`Inc.
`
`Related Matters: The ’605 Patent was involved in a completed lawsuit
`
`entitled Power Integrations, Inc. v. Fairchild Semi. Int’l Inc., No. 1:08-cv-00309
`
`(D. Del.) (“D. Del. Litigation”). The outcome of this lawsuit is pending appeal in
`
`Power Integrations, Inc. v. Fairchild Semi. Int’l., Inc., No. CAFC-15-1329.1 ON
`
`Semiconductor was not and is not involved in any way with the above related
`
`matter.
`
`Petitioner has previously filed petitions for IPR against other patents held by
`
`Patent Owner, including U.S. Patent 6,212,079 (IPR2016-000809), and U.S. Patent
`
`6,538,908 (IPR2016-00995). In addition, Petitioner is concurrently filing petitions
`
`for IPR against other patents held by Patent Owner, including U.S. Patent
`
`6,212,079, U.S. Patent 6,107,851, U.S. Patent 6,249,876, U.S. Patent 6,538,908,
`
`
`1 Associated appeal Power Integrations, Inc. v. Fairchild Semi. Int’l., Inc., No.
`CAFC-15-1388 was consolidated with No. CAFC-15-1329.
`
`
`
`2
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`and U.S. Patent 8,115,457.
`
`Lead Counsel: Lead Counsel is Roger Fulghum (Reg. 39,678) of Baker
`
`Botts L.L.P.; Back-up Counsel are Brian Oaks (Reg. 44,981) and Brett Thompsen
`
`(Reg. 69,985) of Baker Botts L.L.P.
`
`Service Information: Baker Botts L.L.P., One Shell Plaza, 910 Louisiana
`
`Street, Houston, Texas 77002-4995; Tel. (713) 229-1234; Fax (713) 229-1522.
`
`Petitioner
`
`consents
`
`to
`
`service
`
`by
`
`electronic
`
`
`at:
`
`ONSemi_605IPR@bakerbotts.com. A Power of Attorney is filed concurrently
`
`herewith under 37 C.F.R. § 42.10(b).
`
`B. Certification of Grounds for Standing
`Petitioner certifies that the ’605 Patent is available for IPR. Petitioner is not
`
`barred or estopped from requesting IPR of the ’605 Patent.
`
`C. Fees
`The Office is authorized to charge any fees that become due in connection
`
`with this Petition to Deposit Account No. 02-0384.
`
`III. OVERVIEW OF THE ’605 PATENT
`
`This section begins with (A) an explanation of switch mode power supply
`
`circuits and the particular problem articulated in the ’605 Patent, followed by
`
`explanations of (B) how the ’605 Patent purports to overcome this problem with a
`
`variable current limit threshold, and (C) how the claims of the ’605 Patent were
`
`
`
`3
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`broadened to cover other uses of a variable current limit threshold.
`
`A. Background of the Technology
`
`The ’605 Patent relates to switch mode power supply circuits. Ex. 1001,
`
`Abstract, 1:24-26. A switch mode power supply may transfer electrical energy
`
`from a power source input (e.g., a wall socket) to the output of the switch mode
`
`power supply through an inductive element, such as a transformer, coupled to a
`
`switch. Id., 5:9-13, 2:4-8, Fig. 4. The duty cycle of the switch (i.e., the ratio of the
`
`on-time of the switch to the overall switching period) may be controlled during
`
`each switching cycle in order to regulate the amount of energy transferred from the
`
`input to the output of the switch mode power supply. Id., 5:37-39, 5:11-13, 3:19-
`
`21.
`
`An example of a switch mode power supply is illustrated in Figure 4 of the
`
`’605 Patent. Id., 5:31-34, Fig. 4. As shown in Figure 4, the power supply receives
`
`power from an external power source at input 355 on the primary side of the power
`
`supply. Id., Fig. 4. A regulation circuit 350 drives a winding of energy transfer
`
`element 320 to supply power at output 300 on the secondary side of the power
`
`supply. Id., Fig. 4; see also id., 5:31-49; Ex. 1003, ¶ 10.
`
`
`
`4
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`primary side
`
`secondary side
`
`input 355
`
`output 300
`
`energy transfer element 320
`
`regulation circuit 350
`(including switch)
`
`
`
`Ex. 1001, Fig. 4; Ex. 1003 ¶ 10.
`
`The regulation circuit of the power supply may control the current and/or the
`
`voltage at output 300. Ex. 1001, 5:37-49. For example, regulation circuit 350
`
`includes an internal switch (i.e., a power MOSFET) that is coupled to the primary
`
`winding of energy transfer element 320. Id., 5:40-43, Fig. 4. Regulation circuit
`
`350 modulates the duty cycle of the switch (i.e., the ratio of the on-time of the
`
`switch to the overall period of each switching cycle) to control the output voltage.
`
`Id., 5:37-39. Similarly, regulation circuit 350 may adjust the current limit of the
`
`switch to control the output current. Id., 5:40-43.
`
`In operation, the regulation circuit may maintain a constant voltage or a
`
`constant current at the output of the power supply. Id., 5:53-56, Fig. 5. As shown
`
`in Figure 5, the power supply may exhibit a constant output voltage region and a
`
`constant output current region. Id., 5:53-56, Fig. 5.
`5
`
`
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`constant output voltage region
`
`output voltage
`threshold
`
`constant output
`current region
`
`
`
`Id., Fig. 5, Ex. 1003 ¶ 12. In the constant output voltage region, the output voltage
`
`remains constant irrespective of the output current. Ex. 1001, 5:56-58. However,
`
`when the output current reaches an output current threshold, the power supply
`
`maintains a constant output current, but at a reduced output voltage. Id., 5:58-63.
`
`As stated in the background of the ’605 Patent, techniques were known in
`
`the art for regulating the output current of a power supply. Id., 1:39-42; Ex. 1003 ¶
`
`13. For example, some switch mode power supplies monitor the current at the
`
`output of the power supply (i.e., at the secondary side) and provide feedback to the
`
`regulator circuit (i.e., at the primary side) to control the energy transfer to the
`
`output. Ex. 1001, 3:5-8; Ex. 1003 ¶ 13. Other switch mode power supplies,
`
`including those disclosed in the ’605 Patent, monitor the current through the switch
`
`in the regulation circuit at the primary side as a proxy for the output current at the
`
`secondary side. See id., 1:44, 3:8-14; Ex. 1003 ¶ 13.
`
`
`
`6
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`To control the output current in the constant current region, the regulation
`
`circuit of the power supply may set an intrinsic current limit threshold. Ex. 1001,
`
`3:18-19. That is, the regulation circuit may monitor the current through the switch,
`
`and turn the switch off when the intrinsic current limit threshold is reached. Id.,
`
`3:19-21, 4:42-44. The intrinsic current limit threshold may be a constant value set
`
`to control the power supply switch in order to maintain a constant current at the
`
`output of the power supply. Id., 3:18-20. Thus, the intrinsic current limit threshold
`
`is used to maintain a constant output current at the output of the power supply
`
`without monitoring the output current at the secondary side. See id., 1:51-2:18; Ex.
`
`1003 ¶ 14.
`
`However, a delay may occur from the time that the switch reaches the
`
`intrinsic current limit threshold and when the control circuitry fully disables the
`
`switch. Ex. 1001, 3:21-23. During this delay, current through the switch continues
`
`to ramp up beyond the intrinsic current limit threshold. Id., 3:24-33. This excess
`
`current through the switch causes an actual current limit that is greater than the
`
`intrinsic current limit threshold. Id., 3:31-33. Moreover, the amount of excess
`
`current will vary based on the input voltage of the power supply. Id., 3:24-27. As
`
`a result, the actual current limit (i.e., the sum of the intrinsic current limit and the
`
`excess current) varies as a function of the input voltage. Id., 3:33-35. Such
`
`variations in the actual current limit may cause undesirable variations in the output
`
`
`
`7
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`current when the power supply is operating in its constant current region. Id.,
`
`3:31-35.
`
`B. Subject Matter of the ’605 Patent
`This section describes how the ’605 Patent (and its parent application) use a
`
`variable current limit threshold to reduce variations in the actual current limit and
`
`thereby achieve an approximately constant output current of the power supply. But,
`
`as explained below in Section III.C, the claims of the ’605 Patent were broadly
`
`drafted such that they do not require a constant actual current limit or a constant
`
`output current.
`
`The ’605 Patent purports to overcome the problem of variations in the actual
`
`current limit caused by different input voltages. Ex. 1001, 3:14-17. For example,
`
`the power supply regulation circuit of the ’605 Patent creates a variable current
`
`limit threshold (i.e., a variable intrinsic current limit) that increases during the on-
`
`time of the power switch. Id., Abstract. Because the ramp up rate of the excess
`
`current in the switch varies with respect to the input voltage to the power supply,
`
`the variable current limit threshold of the ’605 Patent may compensate for changes
`
`in the input voltage that might otherwise cause variations in the actual current
`
`limit, and thus variations in the output current. Id., 3:45-55. The ’605 Patent’s
`
`implementation of this variable intrinsic current limit threshold is explained
`
`directly below, followed by an explanation of how this variable intrinsic current
`
`
`
`8
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`limit threshold compensates for input voltage variations to provide a stable actual
`
`current limit.
`
`Figure 1 of the ’605 Patent illustrates a regulation circuit for implementing a
`
`variable current limit threshold in a power supply.
`
`regulation circuit
`
`switch
`
`Ex. 1001, Fig. 1; Ex. 1003 ¶ 17. Oscillator 5 controls the timing of MOSFET 2
`
`(i.e., the power supply switch). Ex. 1001, 4:16-17, 1:11-14. The rising edge of
`
`clock signal 10 triggers the beginning of the power switch cycle. Id., 4:19-20.
`
`Clock signal 10 sets latch 90 such that the control signal output from the latch turns
`
`the switch on (i.e., MOSFET 2 is enabled to begin conducting). Id., 4:20-24.
`
`As shown in Figure 1, OR gate 85 has three inputs and is coupled to the reset
`
`of latch 90. Id., Fig. 1. Thus, any one of three occurrences may reset latch 90 to
`
`turn the switch off. In the constant voltage region, PWM comparator 32 may reset
`
`latch 90 based on a voltage feedback from the output of the power supply. Id., Fig.
`
`
`
`9
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`1, 4:50-53. In the constant current region, comparator 70 may reset latch 90 if the
`
`switch current exceeds the current limit threshold. Id., 4:47-49. Finally, if latch 90
`
`is not reset before the end of the switch cycle, then maximum duty cycle signal
`
`DMAX 15 may reset the latch at the end of the switch cycle (i.e., falling edge of
`
`DMAX 15). Ex. 1001, 4:25-26; Ex. 1003 ¶ 17. When reset, latch 90 creates an
`
`output control signal that turns the switch off. Ex. 1001, 4:26-28.
`
`As discussed above, the regulation circuit of the ’605 Patent may generate a
`
`variable current limit threshold to control the regulation circuit switch. Id., 4:29-
`
`33. For example, oscillator 5 generates a sawtooth signal 20 that increases during
`
`the on-time of the regulation circuit switch. Id., 4:56-61. Sawtooth signal 20 is
`
`applied to the base of NPN transistor 30 such that the current in resistor 25 linearly
`
`increases with the on-time of the switch. Id., 4:34-37. The current through resistor
`
`25 is mirrored by current mirror 40 and combined with constant current source 50.
`
`Id., 4:37-39. The combined current is applied to resistor 17 to create a variable
`
`intrinsic current limit threshold at node 22. Id., 4:39-42. Thus, the current limit
`
`threshold at node 22 comprises both a constant component and variable component
`
`that linearly increases during the duty cycle of the power switch. Id., 4:34-42.
`
`Figure 2 of the ’605 Patent illustrates the variable intrinsic current limit
`
`threshold created by the regulation circuit.
`
`
`
`10
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`variable current
`limit threshold
`
`
`
`Id., Fig. 2; Ex. 1003 ¶ 18. As illustrated, sawtooth signal 20 linearly increases
`
`during the switching cycle. Ex. 1001, 4:34-37, Fig. 2. The regulation circuit of the
`
`power supply uses sawtooth signal 20 to create the variable intrinsic current limit
`
`threshold 22. Id., 4:54-5:4, Fig. 2. During each switching cycle, the variable
`
`intrinsic current limit threshold begins at constant value K1 and increases
`
`proportionally to the time elapsed (e.g., K2*telapsed). Id., 5:1-4.
`
`Comparator 70 may monitor the current through the power switch, and
`
`disable the switch when the current reaches the variable intrinsic current limit
`
`threshold. Id., 4:47-49. For example, node 37, one input to comparator 70, is
`
`proportional to the drain current (IDRAIN 7) across the power supply switch. Id.,
`
`4:42-45. The other input to comparator 70 is the variable current limit threshold at
`
`node 22. Id., 4:48, Fig. 1. When the voltage at node 37 (e.g., representing the
`
`current through the switch) exceeds the voltage at node 22 (e.g., representing the
`
`variable intrinsic current limit threshold), comparator 70 resets latch 90, thereby
`
`
`
`11
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`disabling the switch. Id., 4:45-49.
`
`The variable intrinsic current limit threshold of the ’605 Patent may reduce
`
`variations in the actual current limit caused by different input voltages. Id., 3:37-
`
`44. For example, when the input voltage is high, the current through the primary
`
`winding of the energy transfer element may increase faster, and thus reach the
`
`intrinsic current limit earlier in the switching cycle when the variable intrinsic
`
`current limit is lower. Id., 3:31-33, 3:40-41, 3:47-51, 4:66-5:4; Ex. 1003 ¶ 22. At
`
`the same time, the higher input voltage may cause a higher amount of excess
`
`current during the delay time (i.e., the delay between when the intrinsic current
`
`limit threshold is reached and when the control circuitry fully disables the switch).
`
`Ex. 1001, 3:31-33. As a result, the lower intrinsic current limit compensates for
`
`the higher excess current during the delay time. See Ex. 1001, 3:36-44; Ex. 1003 ¶
`
`22.
`
`Conversely, when the input voltage is low, the current through the primary
`
`winding of the energy transfer element may increase slowly, and thus reach the
`
`intrinsic current limit later in the switching cycle when the variable intrinsic
`
`current limit is higher. Ex. 1001, 3:52-53; Ex. 1003 ¶ 23. The lower input voltage,
`
`however, may cause a lower amount of excess current in the delay time. Ex. 1001,
`
`3:28-31. As a result, the higher intrinsic current limit compensates for the lower
`
`excess current during the delay time. See id., 3:36-44; Ex. 1003 ¶ 23.
`
`
`
`12
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`Accordingly, the actual current limit (i.e., the sum of the current limit and the
`
`excess current) may become constant across different input voltages as a result of
`
`the variable intrinsic current limit threshold. Id., 3:14-18, Abstract; Ex. 1003 ¶ 23.
`
`In sum, the ’605 Patent discloses a variable intrinsic current threshold to
`
`achieve a constant actual current limit. Id., 3:28-33. The constant actual current
`
`limit may reduce variation in the output current caused by changes to the input
`
`voltage in order to create an approximately constant output current below an output
`
`threshold voltage. Id., 3:14-18, 3:39-40. However, as explained in the next
`
`section, the claims of the ’605 Patent were broadened such that they do not require
`
`a constant actual current limit or a constant output current.
`
`C. The History of the ’605 Patent
`
`The ’605 Patent is a continuation of U.S. App. No. 11/784,560, filed on
`
`April 6, 2007, now U.S. Patent No. 7,646,184, which is a continuation of
`
`application U.S. App. No. 11/397,524, filed on April 3, 2006, now U.S. Patent No.
`
`7,215,105, which is a continuation of U.S. App. No. 10/892,300, filed on July 15,
`
`2004, now U.S. Patent No. 7,110,270 (“the ’270 Patent”). See Ex. 1001.
`
`Patent Owner asserted claims 6-9 the ’270 Patent in the D. Del. Litigation.
`
`Ex. 1006. Independent claim 6 of the ’270 Patent recites a power supply regulator
`
`comprising:
`
`
`
`13
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`a comparator having first and second inputs and an
`output, the first input of the comparator to sense a voltage
`developed by a switch, during an on time of the switch,
`the second input of the comparator coupled to receive a
`current limit threshold signal to increase during the on
`time of the switch; and
`a control circuit to generate a control signal in
`response to the output of the comparator, the control
`signal to be coupled to a control terminal of the switch to
`control switching of the switch to provide a power supply
`to have an output
`characteristic having an
`approximately constant output current below an output
`threshold voltage, the variable current limit threshold
`signal to vary between a first level and a second level
`during a time when the switch is to be on in response to
`the control signal.
`Ex. 1002, Claim 6. (emphasis added). As shown, claim 6 recites a “variable
`
`current limit threshold” as well as the “constant output current” that results from
`
`the variable current limit threshold. Claim 6 of the ’270 Patent is thus directed to a
`
`variable current limit threshold used for the specific purpose disclosed in the
`
`specification and described above (i.e., to maintain an output characteristic having
`
`an approximately constant output current below an output threshold voltage). See
`
`supra Section III.B.
`
`Over a year into the D. Del. Litigation, the Patent Owner filed the
`
`
`
`14
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`continuation application that is now the ’605 Patent. See Ex. 1002. Claim 1 of the
`
`’605 Patent is the only independent claim. As shown below, claim 1 recites the
`
`“variable current limit threshold,” but does not include the “constant output
`
`current” limitation:
`
`A power supply regulator, comprising:
`a comparator having a first input coupled to sense
`a voltage representative of a current flowing through a
`switch during an on time of the switch, the comparator
`having a second input coupled to receive a variable
`current limit threshold that increases during the on
`time of the switch;
`a feedback circuit coupled to receive a feedback
`signal representative of an output voltage at an output of
`a power supply; and
`a control circuit coupled to generate a control
`signal in response to an output of the comparator and in
`response to an output of the feedback circuit, the control
`signal to be coupled to a control terminal of the switch to
`control switching of the switch.
`Ex. 1001, Claim 1. (emphasis added). A comparison of the claims in the ’270
`
`Patent and the ’605 Patent illustrate how the claims of the ’605 Patent were
`
`broadened beyond the scope of the purported invention described in the common
`
`specifications of the patents.
`
`With broadened claim 1 of the ’605 Patent, Patent Owner seeks to cover any
`
`
`
`15
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`power supply regulator with a variable current limit threshold, regardless of
`
`whether the variable current limit threshold is used for the purpose described in the
`
`shared specification of the ’270 and ’605 Patents. However, this expansion of
`
`claim scope is an overreach that encompasses prior art switch mode power supplies
`
`that utilized variable current limit thresholds for other purposes. See State
`
`Contracting & Eng’g Corp. v. Condotte Am., Inc., 346 F.3d 1057, 1068 (Fed. Cir.
`
`2003) (a reference may be “directed to an entirely different problem than the one
`
`addressed by the inventor, . . . yet the reference is still anticipatory if it explicitly or
`
`inherently discloses every limitation recited in the claims.”). As described below,
`
`the prior art de Sartre patent discloses one such switch mode power supply, which
`
`utilizes a current limit threshold that varies while the switch is on, albeit for a
`
`different purpose than described by the shared specification of the ’270 and ’605
`
`Patents.
`
`IV. SUMMARY OF PRIOR ART
`
`A. de Sartre
`
`United States Patent No. 4,692,853 by de Sartre et al. (“de Sartre”) issued on
`
`September 9, 1987 (see Ex. 1005), and thus qualifies as § 102(b) prior art. de
`
`Sartre was not considered during the original prosecution of the ’605 Patent or
`
`during the D. Del. Litigation. See Ex. 1001, Ex. 1010.
`
`de Sartre discloses a switch mode power supply that includes two integrated
`
`
`
`16
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`circuits: “regulation circuit CI1” and “regulation circuit CI2.”
`
`power source 10
`
`primary side
`
`secondary side
`
`switch
`sense resistor
`
`output Vs
`
`Regulation circuit CI1
`
`Regulation circuit CI2
`
`
`
`Ex. 1005, Fig. 1. Regulation circuit CI1, located on the primary side of the power
`
`supply, may control the base of power transistor TP (e.g., a switch). Id., 1:30-31.
`
`Transistor TP controls the flow of current from electric mains line 10 (i.e., the
`
`power source) into the primary winding of the transformer. Id., 1:28-45, Fig. 1.
`
`On the secondary side of the power supply, regulation circuit CI2 monitors the
`
`output voltage Vs and sends regulation signals back to regulation circuit CI1
`
`through transformer TX. Id., 1:36-41, Fig. 1.
`
`During normal operation of the power supply, regulation circuit CI2 sends
`
`regulation signals to regulation circuit CI1 to cause transistor TP to turn on and off.
`
`Id., 10:45-50. The regulation signals from regulation circuit CI2 are received at
`
`
`
`17
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`terminal 40 of regulation circuit CI1. Id., Fig. 2, 9:56-57. Positive control signals
`
`at terminal 40 cause transistor TP to turn on, and negative control signals cause
`
`transistor TP to turn off during the switching cycle. Id., 10:45-50.
`
`To protect transistor TP, the power supply may utilize a safety mode during
`
`start up or when a dangerous overcurrent condition is detected. Id., 2:48-53.
`
`Regulation circuit CI1 may detect start up or overcurrent through terminal 40 (i.e.,
`
`absence of regulation signals from regulation circuit CI2) and terminal 44 (i.e.,
`
`current measuring input from transistor TP). Id., 8:46-51, 11:49-53.
`
`from regulation circuit CI2
`
`regulation circuit CI1
`
`signal to switch
`
`current measuring input from sense resistor
`
`Id., Fig. 2.
`
`In safety mode, the regulation circuit slowly ramps up the current through
`
`transistor TP to prevent destruction of the transistor. Id., 2:9-18. Bursts of
`
`triggering pulses may be sent to transistor TP during short enablement windows in
`
`
`
`18
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`which the current limit threshold is gradually increased. Ex. 1005, Abstract,
`
`11:39-44. Oscillator 82 generates a low frequency (e.g., 1Hz) sawtooth waveform
`
`82 that comparator 88 in turn uses to generate a short (10% duty cycle) periodic
`
`square waveform (i.e., as enablement window). Id., 7:8-28, 8:55-64.
`
`enablement windows
`
`current limit
`increasing during
`on-time of switch
`
`variable current
`limit threshold
`
`Id., Fig. 4. To protect transistor TP, the current limit from circuit 90 (i.e., the
`
`current limit threshold at which transistor TP is turned off by comparator 92) is set
`
`to a low value (Vs2) and then gradually increased to the current limit threshold
`
`used during normal operation of the power supply (Vs1). Id., 9:19-25, Fig. 2,
`
`Fig. 4; Ex. 1003 ¶ 33.
`
`Each burst of triggering pulses to transistor TP during an enablement
`
`window is subject to a “current limitation threshold [that] passes progressively
`
`from its second relatively low value to its normal higher value.” Ex. 1005, 9:39-
`
`42. Ex. 1003 ¶ 34. Each triggering pulse may enable, or turn on transistor TP. Ex.
`
`1005, 8:55-65, 10:45-46; Ex. 1003 ¶ 34. As illustrated below, the variable current
`19
`
`
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`limit threshold increases during each triggering pulse to transistor TP (i.e., during
`
`the on-time of the switch).
`
`on-time of the switch
`(e.g., transistor TP)
`
`variable current limit threshold increasing
`during the on-time of the switch
`
`
`
`Ex. 1005, Fig. 4 (excerpt and annotation); Ex. 1003 ¶ 34.
`
`In sum, de Sartre discloses a power supply that operates in safety mode
`
`during start up and overcurrent conditions. Ex. 1005, 2:48-53, Abstract. In safety
`
`mode, transistor TP may be turned on as the current limit threshold is increased.
`
`Id., 9:19-25, Fig. 2, Fig. 4; Ex. 1003 ¶ 35. Thus, de Sartre discloses a current limit
`
`threshold that increases during the on-time of the switch. Ex. 1003 ¶ 35. The
`
`purpose of the variable current limit threshold in de Sartre (i.e., to protect transistor
`
`TP during start up and overcurrent conditions) may be different than that described
`
`in the specification of the ’605 Patent (i.e., reduce variations in the actual current
`
`limit caused by different input voltages). Id., ¶ 35. However, as explained in
`
`Section III.C, the claims of the ’605 Patent were broadened to encompass prior art
`
`switch mode power supplies that utilized variable current limit thresholds for other
`
`
`
`20
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`purposes.
`
`V. CLAIM CONSTRUCTION
`
`In an IPR, claims are given their “broadest reasonable construction in light
`
`of the specification.” See 37 C.F.R. § 42.100(b); In re Cuozzo Speed Technologies,
`
`LLC, 793 F.3d 1268, 1275-78 (Fed. Cir. 2015). Thus, the words of the claim are
`
`given their plain meaning unless inconsistent with the specification. See Aventis
`
`Pharma S.A. v. Hospira, Inc., 675 F.3d 1324, 1330 (Fed. Cir. 2012); see also In re
`
`Zletz, 893 F.2d 319, 321 (Fed. Cir. 1989). Petitioner does not believe that
`
`construction of any claims is required for, or material to, the resolution of this IPR.
`
`VI. THERE
`IS A REASONABLE LIKELIHOOD THAT THE
`CHALLENGED CLAIMS ARE UNPATENTABLE
`
`A. Ground 1: de Sartre Anticipates Claims 1, 2, 5, and 9 Under 35
`U.S.C. § 102
`
`1. Claim 1
`
`Claim 1[pre]:2 “A power supply regulator, comprising:”
`
`de Sartre discloses a “chopped power supply control circuit.” Ex. 1005,
`
`Abstract. The power supply includes various circuit elements, including regulation
`
`circuit CI1 and regulation circuit CI2, which regulate the output of the power
`
`supply. Ex. 1005, 1:28-45, Fig. 1.
`
`
`2 Petitioner contends that the preambles of each of the challenged claims are non-
`limiting, but are nonetheless disclosed by the prior art.
`21
`
`
`
`
`
`Petition for IPR of U.S. Patent 7,834,605
`
`Regulation circuit CI1
`
`Regulation circuit CI2
`Id., Fig. 1. Accordingly, de Sartre discloses a “power supply regulator,” as recited
`
`by the preamble of claim 1. Ex. 1003, ¶ 39.
`
`1[pre]. A
`power
`supply
`regulator,
`comprising:
`
`
`de Sartre:
`Ex. 1005, Abstract: “A chopped power supply control circuit is
`provided intended to receive regulation control signals and to
`produce square waves for enabling a switch.”
`
`Ex. 1005, 1:28-45: “In chopped power supply architecture
`proposed by the applicant and shown in FIG. 1, two integrated
`circuits are used. One of the circuits CI1, serves for controlling the
`base of a power transistor TP for applying thereto periodic enabling
`and disabling control signals. The base control circuit CI1 is placed
`on the primary winding side (EP) of the transformer (TA) for
`reasons which will be better under
Accessing this document will incur an additional charge of $.
After purchase, you can access this document again without charge.
Accept $ Charge
Still Working On It
This document is taking longer than usual to download. This can happen if we need to contact the court directly to obtain the document and their servers are running slowly.
Give it another minute or two to complete, and then try the refresh button.
A few More Minutes ... Still Working
It can take up to 5 minutes for us to download a document if the court servers are running slowly.
Thank you for your continued patience.
This document could not be displayed.
We could not find this document within its docket. Please go back to the docket page and check the link. If that does not work, go back to the docket and refresh it to pull the newest information.
Your account does not support viewing this document.
You need a Paid Account to view this document. Click here to change your account type.
Your account does not support viewing this document.
Set your membership
status to view this document.
With a Docket Alarm membership, you'll
get a whole lot more, including:
- Up-to-date information for this case.
- Email alerts whenever there is an update.
- Full text search for other cases.
- Get email alerts whenever a new case matches your search.
One Moment Please
The filing “” is large (MB) and is being downloaded.
Please refresh this page in a few minutes to see if the filing has been downloaded. The filing will also be emailed to you when the download completes.
Your document is on its way!
If you do not receive the document in five minutes, contact support at support@docketalarm.com.
Sealed Document
We are unable to display this document, it may be under a court ordered seal.
If you have proper credentials to access the file, you may proceed directly to the court's system using your government issued username and password.
Access Government Site
