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                                                                   EXHIBIT 10.13


JULY 26, 1995

Mr. William C. Caldwell
17101 San Pedro Circle
Foutain Valley, CA 92708

Dear Bill:

         This letter confirms the following agreements with you regarding
termination of your employment with QLogic Corporation, a Delaware corporation
("QLogic"):

         1. It is acknowledged that on July 26, 1995 (the "Termination Date")
you resigned as an employee and officer of QLogic and any or all of its
subsidiaries or affiliates.

         2. You will be paid your base salary, allowances, and benefits for your
services as an employee of QLogic, as in effect immediately prior to the
Termination Date, through July 26, 1995; provided, however, that you will not
accrue any additional entitlement to any employee benefits or be entitled to
receive vacation or sick leave benefits after the Termination Date. You will
also not receive any bonus for services prior to the Termination Date.

         3. After the Termination Date, QLogic will provide you with gross
separation payments equal to the regular amount of your prorated base salary for
each payroll period, as in effect immediately prior to the Termination Date.
Such separation payments shall be payable over the six (6) month period
commencing July 27, 1995 and ending January 26, 1996 (the "Separation Payment
Period") and shall be paid in equal installments on the customary QLogic salary
payment days. Such separation payments are beyond that provided by QLogic policy
or by law. There will, of course, be deductions and withholdings from the gross
amount for applicable federal, state and local income and employment taxes,
FICA, etc. Unless you make other arrangements with QLogic, checks will be mailed
to your home or deposited in your bank if you so designate.

         4. After the Termination Date, the group health benefits you were
receiving as of the Termination Date will cease. You may extend after the
Termination Date, for yourself and your covered dependents, the group health
coverage that you
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were receiving as of the Termination Date by selecting COBRA coverage. You can
only extend the type of coverage in effect as of the Termination Date, without
any additions, deletions, or modifications. If you elect to continue your
coverage under COBRA, QLogic will pay the applicable premiums for yourself and
your electing covered dependents through the end of the Separation Payment
Period. After the end of the Separation Payment Period, in order to continue
coverage under COBRA, you will be required to pay the full amount of the
applicable premium cost of providing benefits and an additional administrative
charge. The payment of the applicable premium through the end of the Separation
Payment Period will be contingent on your continued eligibility for COBRA
continuation coverage and will not operate to extend the continuation coverage
period required by the provisions of applicable law.

         5. Anything set forth in this letter to the contrary notwithstanding,
if you accept and commence part-time or fulltime employment (as an employee,
consultant, or otherwise) with any other employer prior to the end of the
Separation Payment Period, the compensation, benefits and payments QLogic would
otherwise be obligated to provide to you under this agreement will be reduced to
the extent of, and by amounts equal to, the total compensation and economic
value of benefits received by you from such other employer for your services
prior to the end of the Separation Payment Period. You will promptly report any
such other employment, compensation, and benefits to QLogic.

         6. The payments and benefits provided for you above shall be in lieu of
and in full satisfaction of any and all obligations of QLogic and any and all
other rights you may otherwise have to compensation and benefits from QLogic,
including, without limitation, any and all rights to compensation or benefits
under or with respect to the management bonus plan, the cash profit sharing
plan, the discretionary bonus plan, the employee stock option plan, vacation,
sick leave, and the like; provided, however, that the indemnification
obligations of QLogic to you with respect to your actions or omissions as an
employee or officer of QLogic or its affiliates shall remain and continue,
without change or amendment, and shall survive this agreement.

         7. On or before July 28, 1995, you will return and/or account for all
QLogic property in your possession, including, without limitation, i.d. badge,
keys, credit cards (telephone, car rental, air travel, etc.) manuals, supplies,
equipment, etc. You will also promptly transfer to QLogic any and all club
memberships purchased by QLogic on your behalf or offered to you as a result of
your employment status with QLogic.
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         8. You will submit to QLogic, within a reasonable period of time, all
outstanding business expenses for reconciliation and reimbursement. QLogic will
pay only for business expenses incurred prior to the Termination Date and only
according to its established expense reimbursement policy.

         9. Before you begin a new employment position, you will inform QLogic
of the name and address of your new employer and the expected date of
commencement of your new employment. You will also inform QLogic if you change
your residence address and/or telephone number so that contact may be maintained
with you at all times during the term of this agreement.

         10. You hereby forever release and discharge QLogic, all of its
respective subsidiaries, and all of their successors, affiliates, assigns,
employees, former employees, attorneys, agents, officers, directors, and
shareholders from any and all causes of actions, judgments, liens, indebtedness,
damages, losses, claims, liabilities, and demands of every kind and character,
known or unknown, suspected, or unsuspected, absolute or contingent, prior to
the date of execution of this agreement including but not limited to claims
arising out of or in any manner relating to (i) your employment with QLogic,
your position as an officer of QLogic or any of its subsidiaries, and/or
termination of such employment or positions; (ii) any restrictions on the right
of QLogic or any of the released parties to terminate employees; (iii) any
common law claims or actions; (iv) any statements made by any of the released
parties; or (v) any federal, state, or governmental statute, regulation, or
ordinance, including, without limitation, title VII of the Civil Rights Act of
1964, the Age Discrimination in Employment Act, the California Fair Employment
and Housing Act, and claims with any division of the California Department of
Industrial Relations or Employment department. You hereby waive any and all
rights you may have under California Civil Code Section 1542 (or any analogous
state law or federal law or regulation) which provides:

A general release does not extend to claims which the creditor does not know or
suspect to exist in his favor at the time of executing the release, which if
known by him must have materially affected his settlement with the debtor.

         The foregoing release does not apply to any of the obligations of
QLogic under this agreement.


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July 26, 1995 
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         11. It is understood and agreed that this agreement is fully
integrated, represents the entire understanding of the parties, and there are no
other agreements, representations, promises, or negotiations which have not been
expressly set forth herein except for the Technical/Professional Employee
Invention and Nondisclosure Agreement or other agreements of similar import
previously executed by you, any outstanding stock option agreements, and any
other employee benefit plans sponsored by QLogic in which you were participating
as of the Termination Date which will remain in effect in accordance with their
terms after termination of your employment as provided therein. Nothing
contained herein shall constitute or imply any admission of liability or
wrongdoing by any party. This agreement can be amended, modified, or terminated
only by an instrument in writing executed by you and the chief executive officer
of QLogic.

         12. You agree that you are still bound by the Technical/Professional
Employee Invention and Nondisclosure Agreement and any and all other agreements
of similar import which you previously executed. You further agree and
understand that pursuant to said agreement you are prohibited for a period of
two years from employing or attempting to employ in competition with QLogic any
of QLogic's employees and that you agree not to divert or attempt to divert by
solicitation or any other means the customers, of QLogic existing at the
Termination Date. You further agree that you will not in any way disparage
QLogic or any of its employees or directors, or engage in any conduct adverse to
QLogic's interests, including but not limited to the disclosure to competitors,
diversion or attempted diversion by solicitation or any other means of any of
QLogic's prospective customers, joint venturers or business opportunities
existing, identified or for which discussions were initiated prior to the
Termination Date, confidential information, technology or proprietary rights
(including without limitation, any of those relating in any manner to "Project
Callisto"). Should you violate this or any other provision of this agreement,
you understand and agree that you will forfeit any and all remaining payments
under this agreement.
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JULY 26, 1995
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13. It is understood and agreed that:

                  a. In the event of any dispute, controversy, or claim
concerning this agreement, its validity, interpretation, enforcement, or breach,
the prevailing party, in addition to all other legal or equitable remedies
possessed, shall recover his or its reasonable attorneys fees and costs in
connection with any such dispute, controversy, or claim. Any such dispute,
controversy, or claim shall be resolved by arbitration in the City of Costa
Mesa, California, in accordance with the then - existing commercial arbitration
rules of the American Arbitration Association, and judgment upon any award
rendered by the arbitrator(s) may be entered by any state or federal court
having jurisdiction thereof. The arbitrator shall have the authority only to
enforce the legal and contractual rights of the parties and shall not add to
modify, disregard or refuse to enforce any contractual provision. The arbitrator
shall have no right, power or jurisdiction to award a party any punitive or
exemplary damages of any kind. The parties acknowledge and agree that by
entering into this agreement they are agreeing to this arbitration provision and
are waiving all rights to a trial by jury. The provisions of California Code of
Civil Procedure Sections 1281, et seq. govern this arbitration provision. The
parties intend that this agreement to arbitrate shall be valid, enforceable, and
irrevocable.

                  b. This paragraph 13 shall only operate to require arbitration
of claims for money damages. Should a party wish to seek injunctive or other
non-monetary relief, those claims shall be brought in a court of competent
jurisdiction.

14. It is understood, acknowledged, and agreed that:

                  a. In consideration of the additional separation payments
provided hereunder, which payments and benefits are beyond those provided by
QLogic policy or by law, you after knowingly and voluntarily waiving various
rights and claims, including any possible claims for age discrimination under
the federal law known as the Age Discrimination and Employment Act of 1967, as
amended. You understand that this waiver does not extend to rights or claims
that may arise after the date this agreement is executed.

                  b. You have been given a period of at least 21 days within
which to consider this letter agreement, and you have consulted with an attorney
regarding it.
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                  c. You understand that you may revoke this letter agreement
within seven days following its execution, and that this letter agreement shall
not become effective or enforceable Until this seven-day revocation period has
expired.

         15. Should any portion, word, clause, phrase, sentence or paragraph of
this letter agreement be declared void or unenforceable, such portion shall be
considered independent and severable from the agreement, the validity of which
shall remain unaffected.

         16. During the Separation Payment Period, you will provide such
assistance as QLogic may reasonably request to transfer all of your
responsibilities to other QLogic employees as promptly and expeditiously as
possible.

         Please confirm your agreement to the foregoing by dating and signing
this letter agreement where indicated below and returning a signed copy to
QLogic.

Sincerely,

QLOGIC CORPORATION

By:
     Joseph F. Pleso
     President and CEO

Agreed this 26th day of July 1995

                               William C. Caldwell