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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
Unitrode Corporation
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(Name of Issuer)
Common Stock
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(Title of Class of Securities)
913283107
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(CUSIP Number)
Check the following box is a fee is being paid with this statement. [ ] (A
fee is not required only if the filing person: (1) has a previous statement on
file reporting beneficial ownership of more than five percent of the class of
securities described in Item 1; and (2) has filed no amendment subsequent
thereto reporting beneficial ownership of five percent or less of such class.)
(See Rule 13d-7.)
*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1945 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to al other provisions of the act (however, see the Notes).
Page 1 of 6 Pages
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13G
Cusip No. 913283107 Page 2 of 6 pages
1. Name of Reporting Person
S.S. or I.R.S. Identification No. of Above Person
WESTPORT ASSET MANAGEMENT, INC.
2. Check the appropriate box if a member of a group* (a) [ ]
(b) [ ]
3. SEC Use Only
4. Citizenship or Place or Organization
CONNECTICUT
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Number of 5. Sole Voting Power
Shares 6,000
Beneficially 6. Shared Voting Power
Owned By 1,797,200
Each 7. Sole Dispositive Power
Reporting 6,000
Person 8. Shared Dispositive Power
With 1,797,200
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9. Aggregate Amount Beneficially Owned by each Reporting Person
1,803,200
10. Check Box if the aggregate amount in row (9) excludes certain shares * [ ]
11. Percent of Class Represented by Amount in Row 9
5.69%
12. Type of Reporting Person*
IA
* SEE INSTRUCTION BEFORE FILLING OUT
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Page 3 of 6 pages
Item 1 (a) Name of Issuer:
UNITRODE CORPORATION
Item 1 (b): Address of Issuer's Principal Executive Offices:
7 CONTINENTAL BOULEVARD
MERRIMACK, NH 03054
Item 2 (a): Name of Person Filing:
WESTPORT ASSET MANAGEMENT, INC.
Item 2 (b): Address of Principal Business Office:
253 RIVERSIDE AVENUE
WESTPORT, CT 06880
Item 2(c): Citizenship:
CONNECTICUT
Item 2(d): Title of Class of Securities:
COMMON STOCK
Item 2 (e): CUSIP Number:
913283107
Item 3. If this stated is filed pursuant to Rules
13d-1(b), or 13d-2(b), check whether the person
filing is a:
(a) ( ) Broker or Dealer registered under
Section 15 of the Act
(b) ( ) Bank as defined in Section 3(b)(6)
of the Act
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Page 4 of 6 pages
(c) ( ) Insurance Company as defined in
Section 3(a) (19) of the Act
(d) ( ) Investment Company registered
under Section 8 of the Investment
Company Act
(e) (X) Investment Adviser registered
under Section 203 of the Investment
Advisors Act of 1940
(f) ( ) Employee Benefit Plan, Pension
Fund which is subject to the
Provisions of the Employee Retire-
ment Income Security Act of 1974
or Endowment Fund; see 'SS'240.13d-1
(b)(1)(ii)(F)
(g) ( ) Parent Holding Company, in accor-
dance with 'SS'240.13d-1(b)(ii)(G)
(Note: See Item 7)
(h) ( ) Group in accordance with 'SS'240.13d-1
(b)(1)(ii)(H)
Item 4. Ownership.
(a) Amount Beneficially owned: 1,803,200 shares
(b) Percent of Class: 5.69%
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote: 6,000
(ii) shared power to vote or to direct the vote:
1,797,200
(iii) sole power to dispose or to direct the
disposition of: 6,000
(iv) shared power to dispose or to direct the
disposition of: 1,797,200
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Page 5 of 6 pages
Item 5. Ownership of Five Percent or Less of a Class
If this statement is being filed to report the fact that as
of the date hereof the reporting person has ceased to be the
beneficial owner of more than five percent of the class of
securities, check the following ( )
Item 6. Ownership of More than Five Percent on Behalf of Another
Person:
A PORTION OF THE SHARES OF COMMON STOCK OF THE ISSUER
REPORTED HEREBY, AMOUNTING IN THE AGGREGATE TO 5.67% OF SUCH SHARES OUTSTANDING,
ARE HELD IN CERTAIN DISCRETIONARY MANAGED ACCOUNTS OF WESTPORT ASSET MANAGEMENT,
INC. (THE "REPORTING PERSON"). THE REMAINING SHARES OF COMMON STOCK OF THE
ISSUER REPORTED HEREBY, AMOUNTING TO 0.02% OF SUCH SHARES OUTSTANDING ARE
BENEFICIALLY OWNED BY OFFICERS AND STOCKHOLDERS OF THE REPORTING PERSON. THE
REPORTING PERSON DISCLAIMS BENEFICIAL OWNERSHIP OF SUCH SHARES BENEFICIALLY
OWNED BY SUCH PERSONS AND DISCLAIMS THE EXISTENCE OF A GROUP.
Item 7. Identification and Classification of the Subsidiary
Which acquired the Security Being Reported on By
the Parent Holding Company.
N/A
Item 8. Identification and Classification of Members of
the Group.
N/A
Item 9. Notice of Dissolution of Group.
N/A
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Page 6 of 6 pages
Item 10. Certification
By signing below, I certify that, to the best of my
knowledge and belief, the securities referred to above were acquired in the
ordinary course of business and were not acquired for the purpose of and do not
have the effect of changing or influencing the control of the issuer of such
securities and were not acquired in connection with or as a participant in any
transaction having such purpose or effect.
Disclaimer
The undersigned expressly declares that the filing of this
Schedule 13G shall not be construed as an admission that such person is, for the
purpose of Section 13(d) or 13(g) of the Securities Act of 1934, the beneficial
owner of any securities covered by this statement.
Signature. After reasonable inquiry and to
the best of my knowledge and belief, I certify
that the information set forth in this statement
is true, complete and correct.
Date: February 16, 1999
WESTPORT ASSET MANAGEMENT, INC.
BY
ANDREW J. KNUTH, CHAIRMAN
STATEMENT OF DIFFERENCES
The section mark shall be expressed as...........................'SS'
