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                                                                    EXHIBIT 10.8

     CONFIDENTIAL MATERIALS OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
     EXCHANGE COMMISSION. THE LOCATIONS OF THE OMITTED MATERIALS ARE INDICATED
     BY THE FOLLOWING NOTATION: [***].

                         SALES REPRESENTATIVE AGREEMENT

THIS AGREEMENT (the "Agreement") is made as of July 5, 2007 between Sanken
Electric Co., Ltd., a Japanese corporation with its principal offices at 3-6-3
Kitano, Niiza-shi, Saitama, Japan ("Sanken"); and Allegro MicroSystems, Inc., a
Delaware corporation with its principal offices at 115 Northeast Cutoff,
Worcester, Massachusetts 01615 ("Allegro").

WHEREAS, Sanken desires that Allegro act as a sales representative for certain
Sanken products in the continents of North and South America, and Allegro is
willing to act in such capacity; and

WHEREAS, Sanken and Allegro wish to stipulate the terms and conditions of such
activity and supersede that certain Representative Agreement between the parties
dated October 1, 1997.

NOW, THEREFORE, the parties hereby agree as follows:

1.   DEFINITIONS.

In this Agreement, the following terms shall have the meanings set forth below:

     1.1 "Commencement Date" means July 20, 2007.

     1.2 "Intellectual Property" means any patent, copyright, trademark or other
industrial or intellectual property right of Sanken in respect of the Products.

     1.3 "Products" means those Sanken products that are listed on Exhibit A to
this Agreement.

     1.4 "Territory" means North and South America, including Puerto Rico.

2.   APPOINTMENT AND ACCEPTANCE.

     2.1 Non-Exclusive Representative. Sanken hereby appoints Allegro as its
non-exclusive sales representative for the Products in the Territory and Allegro
accepts such appointment, subject to the terms of this Agreement. It is agreed
that Allegro may solicit orders through sub-representatives in the Territory.

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     2.2 Scope of Appointment. Allegro shall not knowingly solicit orders from
customers who intend to sell the Products outside of the Territory.

     2.3 Product Modification or Discontinuance. Sanken may modify Products or
discontinue the production of any or all of the Products at any time at its sole
discretion. Sanken shall provide reasonable notice of such changes to Allegro
and Sanken shall be responsible for resolving any customer issues resulting from
its modification or discontinuation of its Products.

     2.4 Relationship. Allegro is a representative of Sanken for the purpose of
procuring orders from customers for Products. The parties are not principal and
agent. Neither party shall have the right or authority to incur or create any
warranty, liability or obligation of any kind on behalf of the other party.

3.   ALLEGRO'S OBLIGATIONS.

Allegro shall, during the term of this Agreement:

     3.1 Use commercially reasonable efforts to promote the sale of Products in
the Territory through a qualified sales organization.

     3.2 Ensure that its sales personnel participate in sales training programs
that Sanken may conduct, and conduct its own internal training to instill in its
personnel, effective sales methods for the Products.

     3.3 Keep Sanken reasonably informed of developments in the market for
Products in the Territory, including changes in applicable regulatory
requirements, and provide Sanken such other information relating to the sale and
service of Products as Sanken may reasonably require from time to time.

     3.4 Refrain from advertising the Products in the Territory, unless Sanken
has been given the opportunity to review and approve advertising materials in
advance.

     3.5 If requested by Sanken and at Sanken's expense, either at the premises
of Allegro or at Sanken's premises, make its employees available for instruction
by Sanken Allegro in the use, sale, maintenance and application of Products.

     3.6 Refrain from becoming a representative or distributor of products
manufactured by a third party that compete with the Products.

     3.7 Bear all expenses associated with selling the Products, such as those
for communication, travel and other sales associated disbursements, incurred in
connection with its activities under this Agreement, unless otherwise agreed by
the parties in writing.


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     3.8 Comply with all applicable laws and regulations relating to the import
of Products into the Territory, including, without limitation, licensing and
documentation requirements in the Territory and such other jurisdictions with
jurisdiction over Allegro and such import activities.

4.   SANKEN'S OBLIGATIONS.

Sanken shall, during the term of this Agreement:

     4.1 Provide adequate training for Allegro employees and reasonable field
sales support.

     4.2 Provide such information and support as may reasonably be requested by
Allegro with respect to Products, including then existing marketing materials,
brochures and other information regarding Products.

     4.3 As mutually agreed with Allegro, participate with Allegro in fairs and
exhibitions in the Territory.

     4.4 Comply with all applicable laws and regulations relating to the export
of Products from their place of manufacture or assembly into the Territory,
including, without limitation, licensing and documentation requirements in the
Territory and such other jurisdictions with jurisdiction over Sanken and such
export activities.

5.   ORDERS, TERMS AND COMMISSIONS.

     5.1 Orders. Orders for Products shall be submitted in accordance with
procedures indicated by Sanken from time to time. Sanken reserves the right to
reject any order at its sole discretion.

     5.2 Terms and Conditions of Sale. Sanken's terms and conditions of sale
shall apply to all sales of Products. No deviation from Sanken's terms and
conditions shall be binding unless accepted in writing by Sanken.

     5.3 Prices. Sanken reserves the right to change Product prices at any time.
Orders accepted by Sanken prior to a price increase will be invoiced at the
price in effect at the time of acceptance. Orders based upon a prior quotation
will be accepted at prices in effect on the date of the quotation if the order
is received by Sanken within thirty (30) days after the date of the quotation.

     5.4 Commissions. Allegro shall be entitled to receive commissions as
specified on Exhibit B to this Agreement.

     5.5 Order Termination. Sanken reserves the right to terminate the balance
of any accepted customer order if Sanken learns that the customer's use of the
Products is not suitable for such customer's application, or if the customer
intends to use the Products in any life-support


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<PAGE>

device or system if a failure of such Product can reasonably be expected to
cause a failure of that life-support device or system or to effect the safety or
effectiveness of that device or system.

6.   INTELLECTUAL PROPERTY.

     6.1 License Grant. During the term of this Agreement, Sanken hereby grants
to Allegro a license and privilege to use the trademarks included within the
Intellectual Property in the Territory for the specific purposes of this
Agreement. Sanken warrants that it owns the rights to the Intellectual Property
in the Territory, or has a valid license to such rights. Sanken shall retain
ownership of its Intellectual Property and Allegro shall not by operation of
this Agreement acquire any ownership interest therein.

     6.2 Protection of Intellectual Property. Allegro will not use any
trademarks or trade names in the Territory that are likely to cause confusion
with the trademarks or trade names of Sanken. Following the receipt of notice or
other knowledge of any actual, threatened or suspected infringement in the
Territory of any Intellectual Property or any claim of a third party that the
sale of Products in the Territory infringes such party's intellectual property
rights, Allegro will promptly notify Sanken thereof. Allegro will assist Sanken,
at Sanken's expense, in maintaining Sanken's ownership rights to the
Intellectual Property in the Territory, including any action against
infringement of the Intellectual Property in the Territory, or negotiation of
any permit or license.

     6.3 Infringement Indemnification. Sanken shall defend and hold Allegro
harmless from and against any and all claims, damages, suits, causes of action,
liabilities or expenses (including without limitation reasonable attorneys'
fees) arising from any allegation or claim that the sale of Products in the
Territory infringes the intellectual property rights of any third party.

7.   TERM AND TERMINATION.

     7.1 Term. This Agreement shall take effect on the Commencement Date and
shall remain in effect for a period of one year. This Agreement may be
terminated as of the one year anniversary of the Commencement Date by either
party upon three (3) months prior written notice to the other party. If neither
party gives such notice of termination, this Agreement shall be renewed for one
additional year. Thereafter, this Agreement shall automatically renew for a
successive one year periods until either party gives notice of termination at
least three (3) months prior to the expiration of any renewal term.

     7.2 Termination. Either party hereto may immediately terminate this
Agreement as follows: (a) if proceedings in bankruptcy or insolvency are
instituted by or against the other party, a receiver or trustee is appointed, or
such party makes an assignment for the benefit of its creditors or enters into
any voluntary arrangement with creditors, or a substantial part of the assets of
such party is the subject of attachment; or (b) upon default by the other party
in the performance of its obligations under this Agreement, whereby such default
is not cured within sixty (60) days after receipt by the defaulting party of
written notice of the default.


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     7.3 Effect of Termination. Upon the termination or expiration of this
Agreement for any reason:

          7.3.1 Allegro will promptly return to Sanken, or otherwise dispose of
as Sanken may instruct, all Confidential Information (as defined in Section
8.1), technical instruction manuals, sales promotion materials, specifications
or other documents relating to any of the Products.

          7.3.2 Allegro will immediately cease to market or advertise the
Products in the Territory.

          7.3.3 Sanken shall satisfy all orders for Products accepted from any
customer by Sanken prior to such termination if the customer order was procured,
at least in part, through the efforts of Allegro.

     7.4 Effect of Non-Completion. Sanken may withhold the payment of
commissions due after the termination or expiration of this Agreement until all
obligations owed by Allegro have been completed.

8.   CONFIDENTIALITY.

     8.1 Confidential Information. Except as provided in Section 8.2, neither
party shall disclose to any third party, nor use for any purpose other than the
purchase or sale of Products under this Agreement, any Confidential Information
of the other party without the other party's prior written consent. As used in
this Agreement, "Confidential Information" shall include but not be limited to
all information regarding current or future Products, designs, marketing plans,
processes, inventions, formulae, pricing and cost information, specifications,
drawings, samples or other confidential or proprietary information or data
furnished by one party to the other. "Confidential Information" shall not
include any information that is publicly known through no fault of the receiving
party, was previously known to or developed by the receiving party or an
employee of the receiving party who has not had access to any Confidential
Information of the disclosing party, or was received from a third party without
breach of any confidentiality obligation imposed on that third party.

     8.2 Permitted Disclosures. A party may disclose Confidential Information
(i) to the extent required by law or by court order or other governmental
action, but only to the extent so ordered; or (ii) to the extent necessary to
implement this Agreement, to the party's employees, agents or subcontractors as
reasonably necessary or appropriate, provided that before disclosure such
recipients are informed of the confidentiality requirements of this Agreement.
The disclosing party shall ensure compliance by its employees, agents or
subcontractors with the confidentiality provisions of this Agreement.


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     8.3 Governmental Filings. Each party shall determine in its sole discretion
whether such party is required to file or otherwise submit this Agreement and/or
any description hereof with or to any governmental authorities or securities
exchanges, including, without limitation, the U.S. Securities and Exchange
Commission, NASDAQ, the Japanese Securities and Exchange Surveillance Commission
or the Tokyo Stock Exchange. If a party (as the Submitting Party) determines
that it is required to file or otherwise submit this Agreement and/or any
description hereof with or to any such governmental authority or securities
exchange, as applicable, then such Submitting Party shall with respect to such
proposed filing or submission: (i) provide a copy of such filing or submission
to the other party (as the Non-Submitting Party) reasonably prior to its filing
or submission, and (ii) to the extent that the Submitting Party intends to
request confidential treatment for any portion or portions of this Agreement,
the Submitting Party will (A) provide a reasonable amount of time for the
Non-Submitting Party's review of such confidentiality request and any redactions
comprising such intended request and (B) give good faith consideration to the
Non-Submitting Party's comments and requests for any additional or different
redactions.

9.   MISCELLANEOUS PROVISIONS.

     9.1 Entire Agreement. This Agreement, and the attached Exhibits,
constitutes the entire understanding between the parties with respect to
Allegro's status as a sales representative for the Products in the Territory,
and supersedes all prior agreements, negotiations and discussions between the
parties regarding such subject matter, including without limitation that certain
Representative Agreement between the parties dated October 1, 1997.

     9.2 Amendments. No amendment or modification of this Agreement shall be
effective unless set forth in writing and signed by a duly authorized
representative of each party.

     9.3 Assignment. Neither party shall assign any or all of its rights and
obligations under this Agreement without the prior written consent of the other
party.

     9.4 Waiver. Any failure by any party to exercise or enforce any right under
this Agreement shall not be deemed a waiver of such party's right thereafter to
enforce each and every term and condition of this Agreement.

     9.5 Force Majeure. The obligations of a party under this Agreement will be
suspended during the period and to the extent that such party is prevented or
hindered from complying therewith by any cause beyond its reasonable control
including (insofar as such cause is beyond such party's control but without
prejudice to the generality of the foregoing expression): strikes, lockouts,
labor disputes, act of God, war, riot, civil commotion, malicious damage,
compliance with any law or governmental order, rule, regulation or direction,
accident, breakdown of plant or machinery, fire, flood or storm. In the event of
either party being so hindered or prevented such party will give notice of
suspension as soon as reasonably possible to the other party stating the date
and extent of such suspension and the cause thereof and the omission to give
such notice will forfeit the rights of such party to claim such suspension. Any
party whose obligations have been suspended as aforesaid will not be deemed to
be in default of


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its contractual obligations nor will any penalties or damages be payable. Any
such party will resume the performance of such obligations as soon as reasonably
possible after the removal of the cause and will so notify the other party. In
the event that such cause continues for more than three months either party may
terminate this Agreement on fourteen (14) days written notice.

     9.6 Indemnification. Each party shall fully indemnify the other party
against all actions, claims, demands, costs, charges, expenses or liabilities
arising from or in connection with any breach of its obligations under this
Agreement. NEITHER PARTY SHALL BE LIABLE TO THE OTHER (OR TO ANYONE ASSERTING A
CLAIM ON A PARTY'S BEHALF) FOR INCIDENTAL, CONSEQUENTIAL, SPECIAL OR PUNITIVE
DAMAGES OF ANY NATURE, INCLUDING WITHOUT LIMITATION LOST PROFITS OR REVENUES.
The obligation of Sanken to so indemnify Allegro under this Section 9.6 is in
addition to any indemnity provided by Sanken to Allegro under Section 6.3.

     9.7 Language. This Agreement was drafted and executed in the English
language.

     9.8 Notices. Notices under this Agreement may be sent by e-mail or courier
service. Notice shall be sent to the address set forth on the first page of this
Agreement or to such other address and contact person as a party may designate,
or to the email address of any such designated contact person.

     9.9 Severability. The invalidity or unenforceability of any portion of this
Agreement shall not affect the validity or enforceability of the remainder of
this Agreement.

     9.10 Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of Japan.

     9.11 Dispute Resolution. The parties shall make best efforts to try to
resolve any and all claims, controversies or difficulties between the parties
("Claims") by mutual discussions in good faith. Should the parties be unable to
reach resolution themselves, Claims shall be finally settled by arbitration as
follows: if Allegro initiates the arbitration proceedings, arbitration will be
held in Tokyo, Japan in accordance with the Commercial Arbitration Rules of the
Japan Commercial Arbitration Association; and if Sanken initiates the
arbitration proceedings, arbitration will be held in the State of Massachusetts
in accordance with the Commercial Arbitration Rules of the American Arbitration
Association.


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IN WITNESS WHEREOF, the parties have executed this Agreement as of the date and
year first written above.

SANKEN ELECTRIC CO., LTD.               ALLEGRO MICROSYSTEMS, INC.


By: /s/ Hirohito Sekine                 By: /s/ Daniel Demingware
    ---------------------------------       ------------------------------------
    Mr. Hirohito Sekine                     Mr. Daniel Demingware
    General Manager, Sales                  Vice President Sales
    Headquarters


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                                                                       EXHIBIT A

                                    Products

AC adapters

Switching mode power supplies

Transformers


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                                                                       EXHIBIT B

                                   Commissions

The following terms shall apply to sales representative commissions payable to
Allegro pursuant to Section 5.4:

     1.   Commission.

     Allegro shall be entitled to a commission of [***] percent ([***]%) of the
     "Net Sales" of Products. The term "Net Sales" shall mean the total revenues
     for Products shipped during a three-month quarter less returns and less the
     amount of any revenues previously included in net sales that Sanken
     determines during such month to be uncollectible.

     2.   Payment in Dollars.

     Payments shall be made to Allegro in U.S. Dollars.

     3.   Exchange Rate.

     Commissions shall be converted from local currency into U.S. Dollars on a
     quarterly basis pursuant to procedures established by the parties from time
     to time.

     4.   Payment Terms.

     Payments shall be made to Allegro by the end of the month following the
     quarter for which quarterly Net Sales are calculated.


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