AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON JUNE 29, 2001
================================================================================

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                   SCHEDULE TO
            TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR 13(e)(1)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

                                (AMENDMENT NO. 5)

                                __________________

                             SILICONIX INCORPORATED
                       (NAME OF SUBJECT COMPANY (ISSUER))

                                  _________________

                          VISHAY INTERTECHNOLOGY, INC.
                                       AND

              VISHAY TEMIC SEMICONDUCTOR ACQUISITION HOLDINGS CORP.
                                   (OFFERORS)

                 (NAMES OF FILING PERSONS (IDENTIFYING STATUS AS
                        OFFEROR, ISSUER OR OTHER PERSON))

                     COMMON STOCK, PAR VALUE $0.01 PER SHARE
                         (TITLE OF CLASS OF SECURITIES)

                                    82707923
                      (CUSIP NUMBER OF CLASS OF SECURITIES)

                                   AVI D. EDEN
                        C/O VISHAY INTERTECHNOLOGY, INC.
                               63 LINCOLN HIGHWAY
                        MALVERN, PENNSYLVANIA 19355-2120
                                 (610) 644-1300

  (NAME, ADDRESS AND TELEPHONE NUMBER OF PERSONS AUTHORIZED TO RECEIVE NOTICES
                 AND COMMUNICATIONS ON BEHALF OF FILING PERSONS)

                                    COPY TO:
                             ABBE L. DIENSTAG, ESQ.
                       KRAMER LEVIN NAFTALIS & FRANKEL LLP
                                919 THIRD AVENUE
                            NEW YORK, NEW YORK 10022
                                 (212) 715-9100

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[ ]   Check the box if the filing relates solely to preliminary communications
      made before the commencement of a tender offer:

      Check the appropriate boxes below to designate any transactions to which
the statement relates:

      [X]  third-party tender offer subject to Rule 14d-1.

      [ ]  issuer tender offer subject to Rule 13e-4.

      [ ]  going-private transaction subject to Rule 13e-3.

      [X]  amendment to Schedule 13D under Rule 13d-2.

      Check the following box if the filing is a final amendment reporting the
results of the tender offer: [ ]

      This Amendment No. 5 amends the Tender Offer Statement on Schedule TO (as
amended, this "Schedule TO"), filed by Vishay Intertechnology, Inc. ("Vishay"),
a Delaware corporation, and Vishay TEMIC Semiconductor Acquisition Holdings
Corp. ("Vishay TEMIC"), a Delaware corporation and a wholly-owned subsidiary of
Vishay. This Schedule TO relates to the offer by Vishay TEMIC to exchange Vishay
shares of common stock, par value $0.10 per share, for each outstanding share of
common stock, par value $0.01 per share, of Siliconix incorporated, a Delaware
corporation, that Vishay and its subsidiaries do not own, upon the terms and
subject to the conditions set forth in the Prospectus dated June 21, 2001 and in
the related Letter of Transmittal, copies of which have been filed as exhibits
to this Schedule TO.

      On June 28, 2001, Vishay issued a press release announcing that the
registration statement for the offer had been declared effective by the
Securities and Exchange Commission. A copy of the press release is incorporated
by reference into this Schedule TO as Exhibit (a)(26).

ITEM 11.

      Item 11 is amended by adding the following:

      On June 28, 2001, Vishay announced that it entered into an agreement to
acquire the infrared components business of Infineon Technologies AG for
approximately $120 million. A copy of the press release announcing the
acquisition is attached as an exhibit hereto.

ITEM 12.  MATERIAL TO BE FILED AS EXHIBITS.

      Item 12 is amended by adding the following exhibit:

(a)(26)   Press Release issued by Vishay on June 28, 2001 in respect of
          effectiveness of the registration statement for the exchange offer
          (incorporated by reference to the filing by Vishay on Form 425 on June
          28, 2001).

(a)(27)   Press Release issued by Vishay on June 28, 2001 in respect of an
          agreement to acquire the infrared components business of Infineon
          Technologies AG.

      After due inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.

                                VISHAY INTERTECHNOLOGY, INC.

                                By: /s/ Avi D. Eden
                                   ----------------------------------
                                Name: Avi D. Eden
                                Title:Vice Chairman of the Board, Executive Vice
                                      President and General Counsel

                                VISHAY TEMIC SEMICONDUCTOR ACQUISITION
                                HOLDINGS CORP.

                                By: /s/ Avi D. Eden
                                   ----------------------------------
                                Name:  Avi D. Eden
                                Title: Vice President
Dated: June 28, 2001

NEWS RELEASE

                                    Contact:

                                    Infineon Technologies AG
                                    Ralph Heinrich, +49 89/234-22404 (Media
                                    Relations) ralph.heinrich@infineon.com
                                    Chris Goodhart, +1 408 501 6389 (USA)
                                    chris.goodhart@infineon.com
                                    Kaye Lim,++65 8400 689 (Asia)
                                    kaye.lim@infineon.com
                                    Investor Relations, +49 89 234 26655
                                    investor.relations@infineon.com

                                    or

                                    Richard N. Grubb,
                                    +1 610 644 1300

FOR IMMEDIATE RELEASE

Vishay will acquire Infineon's infrared components business -- Infineon
focuses on core business -- Vishay expands market position

      MUNICH, Germany & MALVERN, Penn.--June 28, 2001--Vishay Intertechnology
Inc., Malvern, Pennsylvania (NYSE: VSH), and Infineon Technologies AG, Munich
(FSE/NYSE: IFX), today announced that Vishay will acquire Infineon's entire
infrared components business with worldwide headquarters in San Jose,
California, for approximately US$ 120 million. Under the terms of the
respective agreement Vishay will take over Infineon's development, marketing
and distribution activities in San Jose and its production facility in
Malaysia. A total workforce of approximately 1,200 is currently employed
within this business. In fiscal year 2000 Infineon's infrared components
business posted revenues of US$ 133 million. Subject to governmental
approvals including the anti-trust authorities, the sale is expected to be
completed by end of July 2001.

      The ownership of the production facility will be transfered in two
steps in order to guarantee a smooth transition. In the first stage, Vishay
will own 19 percent of Infineon Technologies Krubong Shd., the newly founded
production joint venture in Malaysia, while Infineon will own 81 percent of
the shares. The remaining shares of the production facility are expected to
be transferred to Vishay during the year 2002.

      `This divestiture is another important step to streamline our
communications portfolio. With the sale of the infrared components business
and the sale of our consumer electronics to Micronas last November, we have
completed our plan to concentrate our wireline activities for the present and
will continue to expand our strategic core activities in the field of local
area networks (LAN) and wide area networks (WAN) as well as in network
access,'' explained Dr. Ulrich Schumacher, President and CEO of Infineon.
``In Vishay, we have found an excellent partner with a mutual interest in
securing the future of the successful and profitable infrared components
business.''

      Dr. Felix Zandman, Chairman and CEO of Vishay stated: ``This
acquisition will enable Vishay to significantly strengthen its current
position in Optoelectronics and specifically in the growing Infrared
Components portion of that market.''

      Supporting the telecommunications and industrial markets, infrared
components are used primarily as optical interfaces in a broad array of
electronic devices including PCs, cell phones, PDAs, industrial automation
systems, set-top boxes, voice/data switching and data transmission equipment.
The products included in the acquisition are optocouplers and solid-state
relays, IrDT (Infrared Data Transmission) modules, DAA (Data Access
Arrangements) kits and custom opto modules.

About Vishay

      Vishay, a Fortune 1,000 Company with year 2000 sales of US$ 2.5
billion, is the largest U.S. and European manufacturer of passive electronic
components (resistors, capacitors, inductors) and a major producer of
discrete semiconductors (diodes, optoelectronics, transistors), IrCDs
(infrared communication devices), and power and analog switching integrated
circuits. The Company's components can be found in products manufactured in a
very broad range of industries worldwide. With headquarters in Malvern,
Pennsylvania, Vishay employs over 20,000 people in 66 facilities in the U.S.,
Mexico, Germany, Austria, the United Kingdom, France, Portugal, the Czech
Republic, Hungary, Israel, Taiwan, China and the Philippines. Vishay can be
found on the Internet at www.vishay.com.

About Infineon

      Infineon Technologies AG, Munich, Germany, offers semiconductor and
system solutions for applications in the wired and wireless communications
markets, for security systems and smartcards, for the automotive and
industrial sectors, as well as memory products. With a global presence,
Infineon operates in the US from San Jose, CA, in the Asia-Pacific region
from Singapore and in Japan from Tokyo. In the fiscal year 2000 (ending
September), the company achieved sales of Euro 7.28 billion with about 29,000
employees worldwide. Infineon is listed on the DAX index of the Frankfurt
Stock Exchange and on the New York Stock Exchange (ticker symbol: IFX).
Further information is available at www.infineon.com.

      This press release contains forward-looking statements based on current
expectations or beliefs, as well as a number of assumptions about future
events. These statements and all other statements that are not historical
facts, are subject to factors and uncertainties that could cause actual
results to differ materially from those described in the forward-looking
statements. The reader is cautioned not to put undue reliance on these
forward-looking statements, which are not a guarantee of future performance
and are subject to a number of uncertainties and other factors, many of which
are outside the control of Infineon and Vishay. The forward-looking
statements in this release address a variety of subjects including, for
example, the expected closing of the acquisition and the potential benefits
of the acquisition. The following factors, among others, could cause actual
results to differ materially from those described in these forward-looking
statements: the integration of Vishay's and Infineon's business; costs
associated with the acquisition; the successful completion of the
acquisition; including applicable regulatory requirements relating to the
transaction; increased competition and technological changes in the
industries in which Vishay and Infineon operate. For a detailed discussion of
these and other cautionary statements, please, refer to Infineon's filings
with the Securities and Exchange Commission.