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                                                                     Exhibit 3.1

                AMENDED AND RESTATED ARTICLES OF INCORPORATION

                                      OF

                       INTEGRATED CIRCUIT SYSTEMS, INC.



                                  ARTICLE ONE

        The name of the Corporation is Integrated Circuit Systems, Inc.


                                  ARTICLE TWO

         The address of the Corporation's registered office in the State of
Pennsylvania is 2435 Boulevard of the Generals, City of Valley Forge, County of
Montgomery, State of Pennsylvania. The name of its registered agent at such
address is Hock E. Tan.


                                 ARTICLE THREE

         The corporation is incorporated under the Business Corporation Law of
1988 of the Commonwealth of Pennsylvania (the "Business Corporation Law")
approved the 5th day of May, 1933, P.L. 364. The nature of the business or
purposes to be conducted or promoted is to engage in any lawful act or activity
for which corporations may be organized under the Business Corporation Law.

                                 ARTICLE FOUR

                             A. AUTHORIZED SHARES

         The total number of shares of capital stock which the Corporation has
authority to issue is 305,000,000 shares, consisting of:

         (1)      5,000,000 shares of Preferred Stock, par value $0.01 per share
                  ("Preferred Stock"); and

         (2)      300,000,000 shares of Common Stock, par value $0.01 per share
                  ("Common Stock").

The Preferred Stock and the Common Stock shall have the rights, preferences and
limitations set forth below.
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                              B. PREFERRED STOCK

         The Preferred Stock may be issued from time to time and in one or more
series. The board of directors of the Corporation is authorized to determine or
alter the powers, preferences and rights, and the qualifications, limitations
and restrictions granted to or imposed upon any wholly unissued series of
Preferred Stock, and within the limitations or restrictions stated in any
resolution or resolutions of the board of directors originally fixing the number
of shares constituting any series of Preferred Stock, to increase or decrease
(but not below the number of shares of any such series of Preferred Stock, then
outstanding) the number of shares of any such series of Preferred Stock, and to
fix the number of shares of any series of Preferred Stock. In the event that the
number of shares of any series of Preferred Stock shall be so decreased, the
shares constituting such decrease shall resume the status which such shares had
prior to the adoption of the resolution originally fixing the number of shares
of such series of Preferred Stock subject to the requirements of applicable law.

                                C. COMMON STOCK

         Section 1. Dividends. Except as otherwise provided by the Business
Corporation Law or these Amended and Restated Articles of Incorporation (the
"Restated Articles"), the holders of Common Stock: (i) subject to the rights of
holders of any series of Preferred Stock, shall share ratably in all dividends
payable in cash, stock or otherwise and other distributions, whether in respect
of liquidation or dissolution (voluntary or involuntary) or otherwise and (ii)
are subject to all the powers, rights, privileges, preferences and priorities of
any series of Preferred Stock as provided herein or in any resolution or
resolutions adopted by the board of directors pursuant to authority expressly
vested in it by the provisions of Part B of this Article Four.

         Section 2. Conversion Rights. The Common Stock shall not be convertible
into, or exchangeable for, shares of any other class or classes or of any other
series of the same class of the Corporation's capital stock.

         Section 3. Cumulative Voting. The shareholders of the Corporation shall
not be entitled to cumulate their votes for the election of directors.

         Section 4. Voting Rights. Except as otherwise provided by the Business
Corporation Law or the Restated Articles and subject to the rights of holders of
any series of Preferred Stock, all of the voting power of the shareholders of
the Corporation shall be vested in the holders of the Common Stock, and each
holder of Common Stock shall have one vote for each share held by such holder on
all matters voted upon by the shareholders of the Corporation.

         Section 5. Registration or Transfer. The Corporation shall keep at its
principal office (or such other place as the Corporation reasonably designates)
a register for the registration of Common Stock. Upon the surrender of any
certificate representing shares of any class of Common Stock at such place, the
Corporation shall, at the request of the registered holder of such certificate,
execute and deliver a new certificate or certificates in exchange therefor
representing in the aggregate the number of shares of such class represented by
the surrendered
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certificate, and the Corporation forthwith shall cancel such surrendered
certificate. Each such new certificate will be registered in such name and will
represent such number of shares of such class as is requested by the holder of
the surrendered certificate and shall be substantially identical in form to the
surrendered certificate. The issuance of new certificates shall be made without
charge to the holders of the surrendered certificates for any issuance tax in
respect thereof or other cost incurred by the Corporation in connection with
such issuance.

         Section 6. Replacement. Upon receipt of evidence reasonably
satisfactory to the Corporation (an affidavit of the registered holder will be
satisfactory) of the ownership and the loss, theft, destruction or mutilation of
any certificate evidencing one or more shares of any class of Common Stock, and
in the case of any such loss, theft or destruction, upon receipt of indemnity
reasonably satisfactory to the Corporation (provided that if the holder is a
financial institution or other institutional investor its own agreement will be
satisfactory), or, in the case of any such mutilation upon surrender of such
certificate, the Corporation shall (at its expense) execute and deliver in lieu
of such certificate a new certificate of like kind representing the number of
shares of such class represented by such lost, stolen, destroyed or mutilated
certificate and dated the date of such lost, stolen, destroyed or mutilated
certificate.

         Section 7. Notices. All notices referred to herein shall be in writing,
shall be delivered personally or by first class mail, postage prepaid, and shall
be deemed to have been given when so delivered or mailed to the Corporation at
its principal executive offices and to any shareholder at such holder's address
as it appears in the stock records of the Corporation (unless otherwise
specified in a written notice to the Corporation by such holder).

         Section 8. Fractional Shares. In no event will holders of fractional
shares be required to accept any consideration in exchange for such shares other
than consideration which all holders of Common Stock are required to accept.
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                                 ARTICLE FIVE

         The Corporation is to have perpetual existence.

                                  ARTICLE SIX

         In furtherance and not in limitation of the powers conferred by
statute, the board of directors is expressly authorized to make, alter or repeal
the Bylaws of the Corporation.

                                 ARTICLE SEVEN

          Meetings of shareholders may be held within or without the State of
Pennsylvania, as the Bylaws may provide. The books of the Corporation may be
kept (subject to any provision contained in the statutes) outside the
Commonwealth of Pennsylvania at such place or places as may be designated from
time to time by the board of directors or in the Bylaws of the Corporation.
Elections of directors need not be by written ballot unless the Bylaws of the
Corporation shall so provide.

                                 ARTICLE EIGHT

          (a) To the fullest extent permitted by the Business Corporation Law as
the same exists or as it may hereafter be amended, no director of the
Corporation shall be personally liable to the Corporation or its shareholders
for monetary damages for breach of fiduciary duty as a director.

         (b) The corporation may indemnify to the fullest extent permitted by
law any person made or threatened to be made a party to an action or proceeding,
whether criminal, civil, administrative or investigative, by reason of the fact
that he, his testator or intestate is or was a director, officer or employee of
the Corporation or any predecessor of the Corporation or serves or served at any
other enterprise as a director, officer or employee at the request of the
Corporation or any predecessor of the Corporation.

         (c) Neither any amendment nor repeal of this Article, nor the adoption
of any provision of these Restated Articles inconsistent with this Article,
shall eliminate or reduce the effect of this Article in respect of any matter
occurring, or any cause of action, proceeding, suit or claim accruing or
arising, or that, but for this Article, would accrue or arise, prior to such
amendment, repeal or adoption of an inconsistent provision.
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                                 ARTICLE NINE

          The Corporation expressly elects not to be governed by Section 2538
(Adoption of Transactions with Interested Shareholders) and the provisions
contained in Subchapters E (Control Transactions), G (Control-Share
Acquisitions), H (Disgorgement by Certain Controlling Shareholders for Employees
Terminated Following Attempts to Acquire Control), I (Severance Compensation for
Employees Terminated Following Certain Control-Share Acquisitions) and J
(Business Combination Transactions - Labor Contracts) of Chapter 25 of the
Business Corporation Law.

                                  ARTICLE TEN

          The Corporation reserves the right to amend, alter, change or repeal
any provision contained in this certificate of incorporation in the manner now
or hereafter prescribed herein and by the laws of the Commonwealth of
Pennsylvania, and all rights conferred upon shareholders herein are granted
subject to this reservation.

                                ARTICLE ELEVEN

                  Section 1. Classification of Directors. At each annual meeting
of shareholders, directors of the Corporation shall be elected to hold office
until the expiration of the term for which they are elected, and until their
successors have been duly elected and qualified; except that if any such
election shall be not so held, such elections shall take place at a
shareholders' meeting called and held in accordance with the Business
Corporation Law. From and after November 15, 2000, the directors of the
Corporation shall be divided into three classes as nearly equal in size as is
practicable, hereby designated as Class I, Class II and Class III. The Class I
and Class II directors shall be those directors who were denominated as member
of Class I and Class II, respectively, prior to the date of the annual meeting
of shareholders held on November 15, 2000, other than any director who was
elected at such annual meeting to serve as a member of Class III. The Class I
directors in office on November 15, 2000 shall hold office until the 2001 annual
meeting of shareholders and until their respective successors shall have been
duly elected and qualified or until their earlier death, resignation or removal;
the Class II directors in office on November 15, 2000 shall hold office until
the 2002 annual meeting of shareholders and until their respective successors
shall have been duly elected and qualified or until their earlier death,
resignation or removal; and the Class III directors elected at the annual
meeting of shareholders held on November 15, 2000 shall hold office until the
2003 annual meeting of shareholders and until their respective successors shall
have been duly elected and qualified or until their earlier death, resignation
or removal. At each annual meeting of shareholders, directors to replace those
of a class whose terms expire at such annual meeting shall be elected to hold
office until the third succeeding annual meeting and until their respective
successors shall have been duly elected and qualified or until their earlier
death, resignation or removal. If the number of directors is hereafter changed,
any newly created directorships or decrease in directorships shall be so
apportioned among the classes as to make all classes as nearly equal in number
as practicable.

                  Section 2. Vacancies. Vacancies occurring on the board of
directors for any reason may be filled by vote of a majority of the remaining
members of the board of directors,
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although less than a quorum, at any meeting of the board of directors. A person
so elected by the board of directors to fill a vacancy shall hold office until
the next election of directors of the class for which such person has been
elected as a director and until his or her successor shall have been duly
elected and qualified or until his or her earlier death, resignation or removal.


                                ARTICLE TWELVE

         The shareholders of the Corporation may not take any action by written
consent in lieu of a meeting, and must take any actions at a duly called annual
or special meeting of shareholders and the power of shareholders to consent in
writing without a meeting is specifically denied. Special meetings of
shareholders of the Corporation may be called only by either the board of
directors pursuant to a resolution adopted by the affirmative vote of the
majority of the total number of directors then in office or by the chief
executive officer of the Corporation.

                               ARTICLE THIRTEEN

         Notwithstanding any other provisions of the Restated Articles or any
provision of law which might otherwise permit a lesser vote or no vote, but in
addition to any affirmative vote of the holders of the capital stock required by
law or the Restated Articles, the affirmative vote of the holders of at least
two-thirds (2/3) of the combined voting power of all of the then outstanding
shares of the Corporation eligible to be cast in the election of directors shall
be required to alter, amend or repeal Articles Eleven or Twelve hereof, or this
Article Thirteen, or any provision thereof or hereof, unless such amendment
shall be approved by a majority of the directors of the Corporation not
affiliated or associated with any person or entity holding (or which has
announced an intention to obtain) twenty percent (20%) or more of the voting
power of the Corporation's outstanding capital stock (other than Bain Capital
Fund VI, L.P., BCIP Associates II, BCIP Trust Associates II, L.P., BCIP
Associates II-B, BCIP Trust Associates II-B, BCIP Associates II-C, PEP
Investments PTY Ltd., and Randolph Street Partners II).