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                                                                   Exhibit 10.12


                                                                      MoSys Inc.
                                                              1020 Stewart Drive
                                                             Sunnyvale, CA 94086
                                                                   July 17, 2000

Mr. F. Judson Mitchell
159 El Pinar
Los Gatos, CA 95032
Tel: (408) 379-8472

Dear Judd,

         I am pleased to offer you a position with Monolithic System Technology,
Inc. ("MoSys" or the "Company") as its Chief Financial Officer, an exempt
position, commencing on or before July 22, 2000. Your supervisor will be myself.
Your base compensation will be one hundred seventy five thousand dollars
($175,000) annually.

         Upon approval of the Company's Board of Directors, you will be granted
an option to purchase 250,000 shares of the Company's common stock. The terms of
such option shall be in accordance with the terms of the Company's stock option
plan. Accordingly, the option will vest 25% at the end of one year of employment
and 2% per month thereafter. The per share exercise price of the option shall be
the fair market value of the Company's common stock on the date of grant as
determined by the Company's Board of Directors, currently deemed to be $8.00 per
share.

         If (i) there is an event of change of control of more than 50% of the
voting power of the Company resulting from a merger, reorganization, sale of all
or substantially all assets or other similar acquisition transaction, and (ii)
you are terminated without Cause or Constructively Terminated (as such terms are
defined below) in connection with such change in control event or during the
twelve month period thereafter, then all unvested stock options granted to you
above shall be immediately accelerated and exercisable.

         "Cause" shall mean (i) an intentional material act of fraud or
dishonesty in connection with employee's duties, or in the course of employment
with the company; (ii) the conviction of a felony; (iii) a willful act by
Employee which is injurious to the Company: or (iv) a willful failure by
Employee to substantially perform his duties, other than a failure resulting
from the Employee's complete or partial incapacity due to physical or mental
illness or impairment.

         "Constructively Terminated" shall mean the termination of the
Employee's employment because of (i) an assignment to Employee of any duties
materially inconsistent with or which constitute a material detrimental change
of Employee's position, duties, responsibilities or status or (ii) a material
reduction in Employee's salary.

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         As a Company employee, you are also eligible to receive those employee
benefits that are generally offered to all employees of the Company.

         You should be aware that your employment with the Company is for no
specified period and constitutes at will employment. As a result, you are free
to resign at any time, for any reason or for no reason. Similarly, the Company
is free to conclude its employment relationship with you at any time, with or
without cause.

         Should your employment be terminated without Cause, the Employee will
receive one quarter (1/4) of the annual salary in effect at the time of the
termination as severance pay from the Company.

         In the event of any dispute or claim relating to or arising out of our
employment relationship, you and the Company agree that all such disputes shall
be fully and finally resolved by binding arbitration conducted by the American
Arbitration Association in Santa Clara County, California. However, we agree
that this arbitration provision shall not apply to any disputes or claims
relating to or arising out of the misuse or misappropriation of the Company's
trade secrets or proprietary information.

         To indicate your acceptance of the Company's offer, please sign and
date this letter in the space provided below and return it to me. This letter,
along with the agreement relating to proprietary rights between you and the
Company, set forth the terms of your employment with the Company and supersede
any prior representations or agreements, whether written or oral. This letter
may not be modified or amended except by a written agreement, signed by the
Company and by you.

         We look forward to working with you at MoSys Inc.

                                           Sincerely,

                                           /s/
                                           ----------------------------------
                                           Chief Executive Officer

ACCEPTED AND AGREED TO this 19 day of July 2000.

/s/ F J Mitchell
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F. Judson Mitchell

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