<PAGE>

                                  AMENDMENT NO. 2 TO
                   SILICONIX KEY PROFESSIONAL PERFORMANCE UNIT PLAN


    The Siliconix Key Professional Performance Unit Plan is hereby amended as
follows, effective as of September 15, 1997:

    1.   A new Article III is hereby added to the Siliconix Key Professional
Performance Unit Plan, to read in full as follows:

    "III.     CHANGE IN CONTROL

              A.   DEFINITION

                   "Change in Control" is any corporate transaction that
                   results in Daimler-Benz AG owning, directly or indirectly,
                   less than 50% of the voting common stock of Siliconix
                   incorporated.

              B.   CHANGE IN CONTROL IN 1997

                   If a change in control is consummated in 1997, bonuses under
                   the Plan for the 1995-1997 period will be paid in full as
                   soon as practicable after the consummation of the change in
                   control.  Bonuses will be computed on the assumption that
                   the latest Siliconix Forecast for 1997 represents the actual
                   results for 1997.  In no event, however, will an employee
                   receive a larger bonus in the event of a change of control
                   than he or she would have received had there been no change
                   in control and bonuses had been paid as usual in February
                   1998.

              C.   CHANGE IN CONTROL IN 1998

                   If a change in control is consummated in 1998, participants
                   will be paid a pro rata share of specified percentages of
                   their bonuses to be received under the Plan, for the period
                   from January 1, 1998 to the date of consummation of the
                   change in control.  The following percentages of the bonuses
                   for the respective three-year periods will be paid:

                   -    100% of the bonus for the 1996-1998 period
                   -    66-2/3% of the bonus for the 1997-1999 period
                   -    33-1/3% of the bonus for the 1998-2000 period

                   The pro rata portion of the participants' bonuses will be
                   paid as soon as practicable after the consummation of the
                   change in control.  Bonuses will be computed on the
                   assumption that the latest Siliconix Forecast for 1998
                   represents the actual results for 1998, and that Siliconix
                   achieved 100% of its corporate goals for 1999 and 2000.  The
                   remaining share of the 


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                   participants' bonuses (from the date of consummation of the
                   change in control to December 31, 1998) will be paid in the
                   same manner and at the same time as if there had been no
                   change in control.  Bonuses will be computed in the usual
                   way, and the portions of the amounts previously paid after
                   consummation of the change in control that were allocable to
                   the 1996-1998, 1997-1999 and 1998-2000 periods,
                   respectively, will be deducted from the payments to be made
                   in February 1999, February 2000 and February 2001.


              D.   AMENDMENT OR TERMINATION OF PLAN IN 1998

                   Notwithstanding any other provision hereof, if a change in
                   control is consummated in 1998, this Siliconix Key
                   Professional Performance Unit Plan may not, prior to January
                   1, 1999, be (i) terminated or (ii) amended in such a way
                   that any participant's bonus hereunder is adversely affected
                   in any manner whatsoever by such amendment."

    2.   The foregoing Article III supersedes and is controlling over all other
provisions of the Siliconix Key Professional Performance Unit Plan.  To the
extent that any other provision of the Siliconix Key Professional Performance
Unit Plan may be inconsistent with any provision of the foregoing Article III,
the said provision of Article III will prevail and will be controlling over said
inconsistent other provision.


Dated:   September 15, 1997                 SILICONIX INCORPORATED


                                            By /s/ Richard J. Kulle 
                                               -----------------------
                                                   Richard J. Kulle
                                                   President & CEO


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