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                                                                     Exhibit 4.5
                                                                     -----------

                     SECOND AMENDMENT TO RIGHTS AGREEMENT

     This Second Amendment, dated as of December 11, 2000 (the "Amendment"),
amends that certain Rights Agreement, originally dated as of December 20, 1994
(the "Rights Agreement") and first amended on August 14, 1996 (the "First
Amendment"), between RF Monolithics, Inc., a Delaware corporation (the
"Company"), and Fleet National Bank (f/k/a BankBoston, N.A., f/k/a the First
National Bank of Boston ("Rights Agent").

     The Board of Directors of the Company has approved a second amendment to
the Rights Agreement pursuant to Section 27 thereof.

     Accordingly, in consideration of the premises and the mutual agreements
herein set forth, the parties hereby agree as follows:

     Section 1.   Certain Definitions. For purposes of this Amendment,
capitalized terms not otherwise defined shall have the meaning given them in the
Rights Agreement.

     Section 2.   Amendment. Section 1(i), as amended by the First Amendment
dated as of August 14, 1996, is hereby amended in its entirety to read as
follows:

     (i)  "Exempt Person" shall mean the following:  (1) Kopp Investment
Advisors, Inc. (and any successor thereto, but no purchaser or assignee thereof
or purchaser or assignee of any shares of Common Shares of the Company by such
Person) ("Kopp"), but only so long as Kopp does not become the Beneficial Owner
of 20% or more of the Common Shares of the Company then outstanding.
Notwithstanding the foregoing, Kopp shall not cease to be an "Exempt Person" as
the result of an acquisition of Common Shares by the Company which, by reducing
the number of shares outstanding, increases the proportionate number of shares
beneficially owned by Kopp to 20% or more of the Common Shares of the Company
then outstanding; provided, however, that if Kopp shall become the Beneficial
Owner of 20% or more of the Common Shares of the Company then outstanding by
reason of share purchases by the Company and shall, after such share purchases
by the Company, become the Beneficial Owner of any additional Common Shares of
the Company, then Kopp shall no longer be deemed to be an "Exempt Person"; and

     (2)  Orin Hirschman ("Hirschman"), but only so long as Hirschman does not
     become the Beneficial Owner of 16.6% or more of the Common Shares of the
     Company then outstanding.  Notwithstanding the foregoing, Hirschman shall
     not cease to be an "Exempt Person" as the result of (1) becoming entitled
     to receive or receiving any additional Common Shares of the Company
     acquired through anti-dilution rights under warrants beneficially owned by
     Hirschman or (2) an acquisition of Common Shares by the Company which, by
     reducing the number of shares outstanding, increases the proportionate
     number of shares beneficially owned by Hirschman to 16.6% or more of the
     Common Shares of the Company then outstanding; provided, however, that if
     Hirschman shall become the Beneficial Owner of 16.6% or more of the Common
     Shares of the Company then outstanding by reason of share purchases by the
     Company or Common Shares acquired through anti-dilution rights under
     warrants beneficially owned by Hirschman, and shall, after such share
     purchases by the Company or triggering of anti-dilution rights, become the
     Beneficial Owner of any additional Common Shares of the Company, then
     Hirschman shall no longer be deemed to be an "Exempt Person."

     Section 3.   Effect of Amendment. Except as expressly amended hereby and by
the First Amendment, the Rights Agreement shall remain in full force and effect.

     Section 4.   Severability. If any term, provision, covenant or restriction
of this Amendment is held by a court of competent jurisdiction or other
authority to be invalid, void or

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unenforceable, the remainder of the terms, provisions, covenants and
restrictions of this Amendment shall remain in full force and effect and shall
in no way be affected, impaired or invalidated.

     Section 5.   Governing Law. This Amendment and each Right Certificate
issued hereunder shall be deemed to be a contract made under the laws of the
State of Delaware and for all purposes shall be governed by and construed in
accordance with the laws of such State applicable to contracts to be made and
performed entirely within such State.

     Section 6.   Counterparts.  This Amendment may be executed in any number of
counterparts and each of such counterparts shall for all purposes be deemed to
be an original, and all such counterparts shall together constitute but one and
the same instrument.

     Section 7.   Descriptive Headings.  Descriptive headings of the several
Sections of this Amendment are inserted for convenience only and shall not
control or affect the meaning or construction of any of the provisions hereof.

     In Witness Whereof, parties hereto have caused this Amendment to be duly
executed and their seals attested, all as of the day and year first above
written.

                                       RF MONOLITHICS, INC.

Attest:
By:______________________________      By: /s/ David M. Kirk
                                          -------------------------------------
Name:____________________________          David M. Kirk
Title:___________________________          President and Chief Executive Officer


                                       Fleet National Bank, f/k/a BankBoston,
                                       N.A., f/k/a THE FIRST NATIONAL BANK OF
                                       BOSTON
Attest:
By:   /s/ Tracy Chipman                By: /s/ Carol Mulvey-Eori
   ------------------------------         -------------------------------------
Name: Tracy Chipman                    Name: Carol Mulvey-Eori
     ----------------------------           -----------------------------------
Title:Account Manager                  Title: Managing Director
      ---------------------------           -----------------------------------

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