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                                  AMENDMENT NO. 2 TO
                   SILICONIX KEY PROFESSIONAL INCENTIVE BONUS PLAN


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

    1.   A new Article X is hereby added to the Siliconix Key Professional
Incentive Bonus Plan, to read in full as follows:

    "X.  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 for the
              1997 calendar year 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, and the
              participants' personal goals will be evaluated as of the date of
              consummation of the change in control.  In no event, however,
              will an employee receive a larger bonus in the event of a change
              in 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 their 1998 bonus for the period from
              January 1, 1998 to the date of consummation of the change in
              control.  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 the participants' personal goals will be
              evaluated as of the date of consummation of the change in
              control.  The remaining share of the 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 amounts previously paid after consummation
              of the change in control will be deducted from the payments to be
              made in February 1999.


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         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
              Incentive Bonus 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 X will apply to all participants in the
Siliconix Key Professional Incentive Bonus Plan, regardless of whether they are
participating as part of a functional unit, part of a product unit, or
otherwise.

    3.   The foregoing Article X supersedes and is controlling over all other
provisions of the Siliconix Key Professional Incentive Bonus Plan.  To the
extent that any other provision of the Siliconix Key Professional Incentive
Bonus Plan may be inconsistent with any provision of the foregoing Article X,
the said provision of Article X 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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