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                                                                 Exhibit 10.24

                       PROMISSORY NOTE/SECURITY INTEREST

$227,867.50                                                    Phoenix, AZ
5.54% Interest                                                 November 8, 1999

     James Thorburn ("Thorburn") for value received, hereby promises to pay
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to the order of Semiconductor Components Industries, LLC ("SCI"), at its
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offices located at 5005 East McDowell Rd., Phoenix, AZ 85008, or such other
place as the holder hereof may designate by notice to Thorburn, the
principal amount of Two Hundred Twenty-Seven Thousand Eight Hundred
Sixty-Seven Dollars and Fifty Cents ($227,867.50)("Principal Amount"), plus
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interest of 5.54 percent per annum ("Interest")(Interest payable hereunder
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shall be computed on the basis of actual days elapsed and a year of 360
days), in lawful money of the United States, in the manner set forth in
Section 1 hereof.

          1. Payment/Prepayment
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          (a) Thorburn shall pay all proceeds that he receives from any sale
of any portion of the Property (as defined in Section 2 below) to the holder
of the Note until the Principal Amount plus accrued Interest is paid in full.
Thorburn shall make such payments as soon as practicable after the date of
such sale (but in no event more than five (5) business days after such sale).
For the avoidance of doubt, no payments of Principal Amount or Interest shall
be due until Thorburn sells the Property or any portion thereof.

          (b) This Note may be prepaid at any time, in whole or in part,
without penalty or premium. Each partial prepayment shall be applied first to
the Interest and then to the Principal Amount. This Note is a non-recourse
note secured by the Property (as defined in Section 2 below).

          2. Acknowledgement
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          Thorburn acknowledges and confirms that (i) SCI has loaned Thorburn
the Principal Amount of the Note for the sole purpose of Thorburn purchasing
70,000 shares of common stock of Zilog Inc. (the "Property") and (ii) he will
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use the proceeds of the Note solely for such purpose.

          3. Event of Acceleration
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          The holder of this Note, by written notice to Thorburn, may declare
the entire outstanding Principal Amount plus Interest immediately due and
payable in the event that Thorburn breaches any of the terms of the Note or
the Pledge and Security Agreement (a form of which is attached
hereto)("Acceleration Event"), in which event the maturity of the then unpaid
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balance of the Note shall be accelerated and shall become immediately due and
payable.


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          4. Security Interest
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     As collateral security for the full and timely payment of all amounts
due under the Note, Thorburn hereby agrees to grant SCI a security interest
in the Property by executing the Pledge and Security Agreement and pledging
the Property to SCI, and Thorburn also agrees to execute any and all
additional documents necessary to provide such security interest.  SCI shall
hold the Property in accordance with the Pledge and Security Agreement and
shall release the Property upon payment of the Principal Amount and Interest
in full, provided that SCI may, at Thorburn's request or upon default as
provided above, dispose of any portion or all of the Property and offset any
proceeds received upon such disposal against SCI's expenses (as provided in
the Pledge and Security Agreement), then against the Principal Amount and
Interest as payment of the Note in full and then pay over the excess
proceeds, if any, to Thorburn.  Upon payment of the Principal Amount and
Interest under the Note, SCG shall promptly release its security interest in
the Property.

          5. Miscellaneous
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     (a) Thorburn shall pay all costs and expenses incurred by the holder in
connection with the collection of the Note, including reasonable attorneys'
fees.

     (b) This Note shall be governed by and construed in accordance with the
laws of Arizona applicable to agreements made and to be performed therein and
cannot be changed orally.

     (c) No delay or failure on the part of the holder of this Note to
exercise any power or right given under this Note, including, but not limited
to, the right to accelerate the amounts due, shall operate as a waiver of
the power or right and no right or remedy of the holder shall be deemed
abridged or modified by any course of conduct.  All rights and remedies
existing hereunder are cumulative and not exclusive of each other or any
rights or remedies otherwise available.

     (d) All notices and other communications hereunder shall be in writing
and shall be deemed given when delivered personally, three days after being
mailed by registered mail, return receipt requested, or the following day if
sent by overnight courier service, to SCI, attention Secretary, at the
address set forth at the beginning of this Note and to Thorburn at 5005 East
McDowell Rd., Phoenix, AZ 85008, or such other address as either party may
specify by notice given pursuant hereto.

     (e) To the extent permitted by applicable law, Thorburn hereby waives
all benefit that might accrue by virtue of any present or future moratorium
laws exempting any of the Property, or any other property, real or personal,
or any part of the proceeds arising from any sale of any such property, from
attachment, levy, or sale under execution, or providing for any stay of
execution to be issued on any judgment recovered on this Note (excepting only
any stay of execution).

     (f) If any term or provision of this Note or the application thereof to
any circumstance shall, to any extent, be invalid, illegal or unenforceable,
such term or such provisions shall be ineffective to the extent of such
invalidity, illegality or unenforceability without invalidating or rendering
unenforceable any remaining terms and provisions hereof or thereof or the
application

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of such term or provision to circumstances other than those as to which it is
held invalid, illegal or unenforceable.

     (g) This Note shall not be transferable, except that SCI may transfer
the Note to any other person or entity without Thorburn's consent.



                                           /s/ James Thorburn
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                                               James Thorburn




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