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                                                                     EXHIBIT 4.5

                                 FIRST AMENDMENT
                                     TO THE
                        LITTELFUSE, INC. RETIREMENT PLAN

      WHEREAS, pursuant to Section 6.4 of the Littelfuse, Inc. Retirement Plan
(the "Plan"), Littelfuse, Inc. (the "Company") has reserved the right to amend
the Plan;

      WHEREAS, certain changes have been made to the Internal Revenue Code of
1986, as amended (the "Code");

      WHEREAS, the Plan must be amended to reflect the changes to the Code;

      WHEREAS, this Amendment is intended as good faith compliance with the
requirements of the Economic Growth and Tax Relief Reconciliation Act of 2001
("EGTRRA") and is to be construed in accordance with EGTRRA and guidance issued
thereunder;

      WHEREAS, this Amendment also amends the minimum required distribution
provisions of the Plan;

      WHEREAS, this Amendment shall supercede the provisions of the Plan to the
extent those provisions are inconsistent with the provisions of this Amendment;

      NOW, THEREFORE, the Company amends the Plan as of January 1, 2002, unless
otherwise indicated, as follows:

      1. Effective for Plan Years commencing after December 31, 2001, amend
Sections 1.1(A)(7) and 4.1(A)(4)(e) by adding the following to the end of each
such sections:

            The annual Compensation of each Participant taken into account in
      determining benefit accruals in any Plan Year beginning after December 31,
      2001, shall not exceed $200,000. Annual Compensation means Compensation
      during the Plan Year or such other consecutive 12-month period over which
      Compensation is otherwise determined under the Plan (the determination
      period). For purposes of determining benefit accruals in a Plan Year
      beginning after December 31, 2001, Compensation for any prior
      determination period shall be $200,000.

            For purposes of the definition of Compensation under this Section
      4.1(e), effective for Plan Years beginning after December 31, 2002,
      amounts under Section 125 of the Code include any amounts not available to
      a Participant in cash in lieu of group health coverage because the
      participant is unable to certify that he or she has other health

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      coverage. An amount will be treated as an amount under Section 125 of the
      Code only if the Employer does not request or collect information
      regarding the Participant's other health coverage as part of the
      enrollment process for the health plan.

            The $200,000 limit on annual Compensation in the immediately
      preceding paragraph shall be adjusted for cost-of-living increases in
      accordance with Section 401(a)(17)(B) of the Code. The cost-of-living
      adjustment in effect for a calendar year applies to annual Compensation
      for the determination period that begins with or within such calendar
      year.

      2. Effective for Plan Years commencing after January 1, 1997, amend
Section 1.4(B) and Section 1.4(C)(1) as follows:

      (B) Reemployment of Vested Terminated Participant Prior to Commencement of
      Payments. If a Participant's service is terminated on or after his Initial
      Vesting Date for a reason other than his normal retirement or early
      retirement as described in Sections 2.1 and 2.2 hereof, respectively, and
      he subsequently reenters the active service of the Employer prior to his
      Annuity Starting Date, and such Participant has not prior to his reentry
      received the full actuarially equivalent value of the benefit provided on
      his behalf under Section 2.4(A)(1), he will become a Participant upon the
      date of such reentry and will be entitled to a reinstatement of the
      Vesting Service and Credited Service that he had accrued on the date of
      termination of his service in lieu of the benefits to which he was
      entitled on such date under Section 2.4(A)(1); provided, however, that
      such Participant's Accrued Deferred Monthly Retirement Income Commencing
      at Normal Retirement Date (or his accrued monthly normal retirement
      income, if applicable) determined as of any given date after the date of
      his reentry shall be reduced on an actuarially equivalent basis, if
      applicable, to take into account any death benefit coverage that was in
      effect under Section 2.4(A) hereof after the date of termination of his
      service and prior to the date of his reentry; and provided further,
      however, that the benefit payable to such Participant commencing at Normal
      Retirement Date shall not be less than the amount to which he was entitled
      under Section 2.4(A)(1) hereof prior to his reentry into the service of
      the Employer.

      (C) Reemployment of Retired or Vested Terminated Participant After
      Commencement of Payments.

            (1) If a Participant, whose service is terminated on or after the
            Effective Date of the Plan and who has received a portion but not
            all of the retirement income to which he is entitled under the
            provisions of Section 2.1, 2.2 or 2.4(A)(1) hereof subsequently
            reenters the active service of the Employer on or after his Annuity
            Starting Date, he shall become a Participant upon the date of such
            reentry and the following provisions shall apply:

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      3. Effective for Plan Years commencing after December 31, 2001, amend
Section 4 by adding new Section 4.7 as follows:

            (A) Modification of Top-Heavy Rules - Effective date. This Section
      shall apply for purposes of determining whether the Plan is a top-heavy
      plan under Section 416(g) of the Code for Plan Years beginning after
      December 31, 2001, and whether the Plan satisfies the minimum benefits
      requirements of Section 416(c) of the Code for such years. This Section
      4.7 amends Section 4.6 of the Plan.

            (B) Determination of Top-Heavy status-Key Employee. Key Employee
      means any employee or former employee (including any deceased employee)
      who at any time during the Plan Year that includes the determination date
      was an officer of the Employer having annual Compensation greater than
      $130,000 (as adjusted under Section 416(i)(1) of the Code for Plan Years
      beginning after December 31, 2002), a 5-percent owner of the Employer, or
      a 1-percent owner of the Employer having annual Compensation of more than
      $150,000. For this purpose, annual Compensation means Compensation within
      the meaning of Section 415(c)(3) of the Code. The determination of who is
      a Key Employee will be made in accordance with Section 416(i)(1) of the
      Code and the applicable regulations and other guidance of general
      applicability issued thereunder.

            (C) Determination of present values and amounts. This Section (C)
      shall apply for purposes of determining the present values of accrued
      benefits and the amounts of account balances of Employees as of the
      determination date.

            (1) Distributions During Year Ending on the Determination Date. The
      present values of accrued benefits and the amounts of account balances of
      an Employee as of the determination date shall be increased by the
      distributions made with respect to the employee under the Plan and any
      Plan aggregated with the Plan under Section 416(g)(2) of the Code during
      the 1-year period ending on the determination date. The preceding sentence
      shall also apply to distributions under a terminated plan which, had it
      not been terminated, would have been aggregated with the Plan under
      Section 416(g)(2)(A)(i) of the Code. In the case of a distribution made
      for a reason other than separation from service, death, or disability,
      this provision shall be applied by substituting 5-year period for 1-year
      period.

            (2) Employees Not Performing Services During Year Ending on the
      Determination Date. The accrued benefits and accounts of any individual
      who has not performed services for the Employer during the 1-year period
      ending on the determination date shall not be taken into account.

            (D) Minimum benefits. For purposes of satisfying the minimum benefit
      requirements of Section 416(c)(l) of the Code and the Plan, in determining
      years of service with the Employer, any service with the Employer shall be
      disregarded to the extent that such service occurs during a Plan Year when
      the Plan benefits (within the meaning of Section 410(b) of the Code) no
      Key Employee or former Key Employee.

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      4. Effective for Plan Years commencing after December 31, 2001, amend
Section 4.1 by adding new Section 4.1(H) as follows:

            (H) Direct Rollovers of Plan Distributions Effective date. This
      Section shall apply to distributions made after December 31, 2001.

            (I) Modification of Definition of Eligible Retirement Plan. For
      purposes of the direct rollover provisions in Section 4.1(I) of the Plan,
      an eligible retirement plan shall also mean an annuity contract described
      in Section 403(b) of the Code and an eligible plan under Section 457(b) of
      the Code which is maintained by a state, political subdivision of a state,
      or any agency or instrumentality of a state or political subdivision of a
      state and which agrees to separately account for amounts transferred into
      such plan from this Plan. The definition of eligible retirement plan shall
      also apply in the case of a distribution to a surviving spouse, or to a
      spouse or former spouse who is the alternate payee under a qualified
      domestic relation order, as defined in Section 414(p) of the Code.

      5. Effective for Plan Years commencing after December 31, 2002, amend the
Plan by adding Second Supplement to Littelfuse, Inc. Retirement Plan as follows:

                                SECOND SUPPLEMENT
                                       TO
                        LITTELFUSE, INC. RETIREMENT PLAN
                AS AMENDED AND RESTATED EFFECTIVE JANUARY 1, 1997

SECTION 1. GENERAL RULES.

      Section 1.1. Effective Date. The provisions of this Second Supplement will
apply for purposes of determining required minimum distributions for calendar
years beginning with the 2003 calendar year.

      Section 1.2. Precedence. The requirements of this Second Supplement will
take precedence over any inconsistent provisions of the Plan.

      Section 1.3. Requirements of Treasury Regulations Incorporated. All
distributions required under this Second Supplement will be determined and made
in accordance with the treasury regulations under Section 401(a)(9) of the Code.

      Section 1.4. TEFRA Section 242(b)(2) Elections. Notwithstanding the other
provisions of this Second Supplement, other than Section 1.4, distributions may
be made under a designation made before January 1, 1984, in accordance with
Section 242(b)(2) of the Tax Equity and Fiscal Responsibility Act (TEFRA) and
the provisions of the Plan that relate to Section 242(b)(2) of TEFRA.

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SECTION 2. TIME AND MANNER OF DISTRIBUTION.

      Section 2.1. Required Beginning Date. The Participant's entire interest
will be distributed, or begin to be distributed, to the Participant no later
than the Participant's required beginning date.

      Section 2.2. Death of Participant Before Distributions Begin. If the
Participant dies before distributions begin, the Participant's entire interest
will be distributed, or begin to be distributed, no later than as follows:

            (a) If the Participant's surviving spouse is the Participant's sole
      designated beneficiary, then, distributions to the surviving spouse will
      begin by December 31 of the calendar year immediately following the
      calendar year in which the Participant died, or by December 31 of the
      calendar year in which the Participant would have attained age 70 1/2, if
      later.

            (b) If the Participant's surviving spouse is not the Participant's
      sole designated beneficiary, then, distributions to the designated
      beneficiary will begin by December 31 of the calendar year immediately
      following the calendar year in which the Participant died.

            (c) If there is no designated beneficiary as of September 30 of the
      year following the year of the Participant's death, the Participant's
      entire interest will be distributed by December 31 of the calendar year
      containing the fifth anniversary of the Participant's death.

            (d) If the Participant's surviving spouse is the Participant's sole
      designated beneficiary and the surviving spouse dies after the Participant
      but before distributions to the surviving spouse begin, this Section 2.2,
      other than Section 2.2(a), will apply as if the surviving spouse were the
      Participant.

      For purposes of this Section 2.2 and Section 5, distributions are
considered to begin on the Participant's required beginning date (or, if Section
2.2(d) applies, the date distributions are required to begin to the surviving
spouse under Section 2.2(a)). If annuity payments irrevocably commence to the
Participant before the Participant's required beginning date (or to the
Participant's surviving spouse before the date distributions are required to
begin to the surviving spouse under Section 2.2(a)), the date distributions are
considered to begin is the date distributions actually commence.

      Section 2.3. Form of Distribution. Unless the Participant's interest is
distributed in the form of an annuity purchased from an insurance company or in
a single sum on or before the required beginning date, as of the first
distribution calendar year distributions will be made in accordance with
Sections 3, 4 and 5 of this Second Supplement. If the Participant's interest is
distributed in the form of an annuity purchased from an insurance company,
distributions thereunder will be made in accordance with the requirements of
Section 401(a)(9) of the Code and the treasury regulations. Any part of the
Participant's interest which is in the form of an

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individual account described in Section 414(k) of the Code will be distributed
in a manner satisfying the requirements of Section 401(a)(9) of the Code and the
treasury regulations that apply to individual accounts.

SECTION 3. DETERMINATION OF AMOUNT TO BE DISTRIBUTED EACH YEAR.

      Section 3.1. General Annuity Requirements. If the Participant's interest
is paid in the form of annuity distributions under the Plan, payments under the
annuity will satisfy the following requirements:

            (a) the annuity distributions will be paid in periodic payments made
      at intervals not longer than one year;

            (b) the distribution period will be over a life (or lives) or over a
      period certain not longer than the period described in Section 4 or 5;

            (c) once payments have begun over a period certain, the period
      certain will not be changed even if the period certain is shorter than the
      maximum permitted;

            (d) payments will either be nonincreasing or increase only as
      follows:

                  (1) by an annual percentage increase that does not exceed the
            annual percentage increase in a cost-of-living index that is based
            on prices of all items and issued by the Bureau of Labor Statistics;

                  (2) to the extent of the reduction in the amount of the
            Participant's payments to provide for a survivor benefit upon death,
            but only if the beneficiary whose life was being used to determine
            the distribution period described in Section 4 dies or is no longer
            the Participant's beneficiary pursuant to a qualified domestic
            relations order within the meaning of Section 414(p);

                  (3) to provide cash refunds of employee contributions upon the
            Participant's death; or

                  (4) to pay increased benefits that result from a Plan
            amendment.

      Section 3.2. Amount Required to be Distributed by Required Beginning Date.
The amount that must be distributed on or before the Participant's required
beginning date (or, if the Participant dies before distributions begin, the date
distributions are required to begin under Section 2.2(a) or (b)) is the payment
that is required for one payment interval. The second payment need not be made
until the end of the next payment interval even if that payment interval ends in
the next calendar year. Payment intervals are the periods for which payments are
received, e.g., bi-monthly, monthly, semi-annually, or annually. All of the
Participant's benefit accruals as of the last day of the first distribution
calendar year will be included in the calculation of the amount of the annuity
payments for payment intervals ending on or after the Participant's required
beginning date.

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      Section 3.3. Additional Accruals After First Distribution Calendar Year.
Any additional benefits accruing to the Participant in a calendar year after the
first distribution calendar year will be distributed beginning with the first
payment interval ending in the calendar year immediately following the calendar
year in which such amount accrues.

SECTION 4. REQUIREMENTS FOR ANNUITY DISTRIBUTIONS THAT COMMENCE DURING
           PARTICIPANT'S LIFETIME.

      Section 4.1. Joint Life Annuities Where the Beneficiary Is Not the
Participant's Spouse. If the Participant's interest is being distributed in the
form of a joint and survivor annuity for the joint lives of the Participant and
a nonspouse beneficiary, annuity payments to be made on or after the
Participant's required beginning date to the designated beneficiary after the
Participant's death must not at any time exceed the applicable percentage of the
annuity payment for such period that would have been payable to the Participant
using the table set forth in Q&A-2 of Section 1.401(a)(9)-6T of the treasury
regulations. If the form of distribution combines a joint and survivor annuity
for the joint lives of the Participant and a nonspouse beneficiary and a period
certain annuity, the requirement in the preceding sentence will apply to annuity
payments to be made to the designated beneficiary after the expiration of the
period certain.

      Section 4.2. Period Certain Annuities. Unless the Participant's spouse is
the sole designated beneficiary and the form of distribution is a period certain
and no life annuity, the period certain for an annuity distribution commencing
during the Participant's lifetime may not exceed the applicable distribution
period for the Participant under the Uniform Lifetime Table set forth in Section
1.401(a)(9)-9 of the treasury regulations for the calendar year that contains
the annuity starting date. If the annuity starting date precedes the year in
which the Participant reaches age 70, the applicable distribution period for the
Participant is the distribution period for age 70 under the Uniform Lifetime
Table set forth in Section 1.401(a)(9)-9 of the treasury regulations plus the
excess of 70 over the age of the Participant as of the Participant's birthday in
the year that contains the annuity starting date. If the Participant's spouse is
the Participant's sole designated beneficiary and the form of distribution is a
period certain and no life annuity, the period certain may not exceed the longer
of the Participant's applicable distribution period, as determined under this
Section 4.2, or the joint life and last survivor expectancy of the Participant
and the Participant's spouse as determined under the Joint and Last Survivor
Table set forth in Section 1.401(a)(9)-9 of the treasury regulations, using the
Participant's and spouse's attained ages as of the Participant's and spouse's
birthdays in the calendar year that contains the annuity starting date.

SECTION 5. REQUIREMENTS FOR MINIMUM DISTRIBUTIONS WHERE PARTICIPANT DIES BEFORE
           DATE DISTRIBUTIONS BEGIN.

      Section 5.1. Participant Survived by Designated Beneficiary. Except as
provided in the adoption agreement, if the Participant dies before the date
distribution of his or her interest begins and there is a designated
beneficiary, the Participant's entire interest will be distributed, beginning no
later than the time described in Section 2.2(a) or (b), over the life of the
designated beneficiary or over a period certain not exceeding:

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            (a) unless the annuity starting date is before the first
      distribution calendar year, the life expectancy of the designated
      beneficiary determined using the beneficiary's age as of the beneficiary's
      birthday in the calendar year immediately following the calendar year of
      the Participant's death; or

            (b) if the annuity starting date is before the first distribution
      calendar year, the life expectancy of the designated beneficiary
      determined using the beneficiary's age as of the beneficiary's birthday in
      the calendar year that contains the annuity starting date.

      Section 5.2. No Designated Beneficiary. If the Participant dies before the
date distributions begin and there is no designated beneficiary as of September
30 of the year following the year of the Participant's death, distribution of
the Participant's entire interest will be completed by December 31 of the
calendar year containing the fifth anniversary of the Participant's death.

      Section 5.3. Death of Surviving Spouse Before Distributions to Surviving
Spouse Begin. If the Participant dies before the date distribution of his or her
interest begins, the Participant's surviving spouse is the Participant's sole
designated beneficiary, and the surviving spouse dies before distributions to
the surviving spouse begin, this Section 5 will apply as if the surviving spouse
were the Participant, except that the time by which distributions must begin
will be determined without regard to Section 2.2(a).

SECTION 6. DEFINITIONS.

      Section 6.1. Designated Beneficiary. The individual who is designated as
the beneficiary under Section 3 of the Plan and is the designated beneficiary
under Section 401(a)(9) of the Code and Section 1.401(a)(9)-l, Q&A-4, of the
treasury regulations.

      Section 6.2. Distribution Calendar Year. A calendar year for which a
minimum distribution is required. For distributions beginning before the
Participant's death, the first distribution calendar year is the calendar year
immediately preceding the calendar year which contains the Participant's
required beginning date. For distributions beginning after the Participant's
death, the first distribution calendar year is the calendar year in which
distributions are required to begin pursuant to Section 2.2.

      Section 6.3. Life Expectancy. Life expectancy as computed by use of the
Single Life Table in Section 1.401(a)(9)-9 of the treasury regulations.

      Section 6.4. Required Beginning Date. The date specified in Section 2.1(D)
of the Plan.

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      IN WITNESS WHEREOF, the Company has caused this First Amendment of the
Plan to be executed by a duly authorized officer of the Company on this ___ day
of December, 2002.

                                        LITTELFUSE, INC.


(Corporate Seal)                        By
                                          ______________________________________
                                           Its__________________________________
ATTEST:

_______________________________
Secretary