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EXHIBIT 10.8


                       AMENDMENT NO. 4 TO LOAN AGREEMENT


        THIS AMENDMENT NO. 4 TO LOAN AGREEMENT (this "Amendment"), is made this
28th day of May, 1999, by and between BURR-BROWN CORPORATION, a Delaware
corporation ("Borrower"), and WELLS FARGO BANK, NATIONAL ASSOCIATION,
successor-by-merger to First Interstate Bank of Arizona, N.A. (the "Bank").

1.     Recitals.

       1.1 Borrower and the Bank (as successor-by-merger to First Interstate
Bank of Arizona, N.A.) are parties to that Loan Agreement dated January 31,
1996, Amendment No. 1 to Loan Agreement dated November 15, 1996, Amendment No. 2
to Loan Agreement dated December 21, 1997, and Amendment No. 3 to Loan Agreement
dated December 2, 1998 (the "Loan Agreement"). Capitalized terms used without
definition herein are used with the meanings attributed to such terms in the
Loan Agreement.

       1.2 Borrower and the Bank desire to modify and amend the Loan Agreement
to provide, among other things, (a) that the definition of Termination Date be
amended, and (b) that the Commitment Fee be reduced.

                   Accordingly, in consideration of the premises and other good
and valuable consideration, the receipt and adequacy of which are acknowledged
by the parties hereto, the parties hereto agree as follows:

2.     Modification and Amendment of Loan Agreement.

       2.1 The Loan Agreement is hereby modified and amended as follows:

                   2.1.1 Definition of "Termination Date". The definition of
"Termination Date" set forth in Annex 1 to the Loan Agreement is hereby amended
in its entirety to read as follows:

                  '"Termination Date" means the earlier of the following: (a)
May 4, 2001 or (b) the date on which the Revolving Commitment is terminated
pursuant to subsection 10.2."'

                   2.1.2 Amendment of Section 3.4 Commitment Fee. The words
"three-eights of one percent (0.375%)" are deleted from the first sentence of
Section 3.4 of the Loan Agreement, and the words "three-sixteenths of one
percent (0.1875%)" are inserted in place thereof. For purposes of calculation,
this amendment shall become effective as of April 1, 1999.

3.     Borrower's Representations; Effectiveness of this Amendment.

       Borrower represents and warrants to the Bank that:

       3.1 Immediately before and after giving effect to this Amendment, the
representations and warranties of the Borrower in Section 7 of the Loan
Agreement are true and correct as though made on the date hereof, except for
changes that are permitted by the terms of the Loan Agreement; and

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       3.2 Immediately before and after giving effect to this Amendment, no
Default and no Event of Default shall have occurred and be continuing.

This Amendment shall become effective when the Bank and Borrower shall each have
executed and delivered to the other a counterpart of this Amendment.

4. Acknowledgements. Borrower and the Bank acknowledge that, as amended hereby,
the Loan Agreement remains in full force and effect and that each reference to
the Loan Agreement shall refer to the Loan Agreement as amended hereby. The
Borrower confirms that it will continue to comply with the covenants set out in
the Loan Agreement and the other Loan Documents, as amended hereby, and that its
representations and warranties set out in the Loan Agreement and the other Loan
Documents, as amended hereby, are true and correct as of the date of this
Amendment in all material respects. The Borrower further represents and warrants
that (i) the execution, delivery and performance of this Amendment by the
Borrower is within its corporate powers and has been duly authorized by all
necessary corporate action; and (ii) this Amendment has been duly executed and
delivered by Borrower and constitutes the legal, valid and binding obligation of
Borrower enforceable against Borrower in accordance with its terms.

5. General.

       5.1 Borrower agrees to reimburse the Bank upon demand for all reasonable
expenses (including reasonable attorneys fees and legal expenses) incurred by
the Bank in the preparation, negotiation and execution of this Amendment and any
other document required to be furnished herewith.

       5.2 This Amendment may be executed in as many counterparts as may be
deemed necessary or convenient, and by the different parties hereto on separate
counterparts, each of which, when so executed, shall be deemed an original but
all such counterparts shall constitute but one and the same instrument.

       5.3 Any provision of this Amendment which is prohibited or unenforceable
in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent
of such prohibition or unenforceability without invalidating the remaining
portions hereof or affecting the validity or enforceability of such provisions
in any other jurisdiction.

       5.4 This Amendment shall be governed by, and construed in accordance
with, the internal law, and not the law of conflicts, of the State of Arizona,
but giving effect to federal laws applicable to national banks.

       5.5 This Amendment shall be binding upon and inure to the benefit of
Borrower and the Bank and their respective successors and assigns.

        5.6 This instrument supersedes and replaces any and all prior versions
of this Amendment No. 4 to Loan Agreement.

       IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 4
to Loan Agreement to be executed as of the day and year first above written.


WELLS FARGO BANK,
 NATIONAL ASSOCIATION

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By: ____________________________________
             Paul C. Hornung
             Vice President


BURR-BROWN CORPORATION

By: ____________________________________
             G. Roger Myers
             Treasurer




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