<PAGE>

                                                                  EXHIBIT 4.2(a)




                                    BYLAWS

                                      OF

                        CENTILLIUM COMMUNICATIONS, INC.

                           (a Delaware Corporation)
<PAGE>

                                   BYLAWS OF

                        CENTILLIUM COMMUNICATIONS, INC.
                           (a Delaware Corporation)

                               TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                            Page
                                                                            ----
<S>                                                                         <C>
ARTICLE I.................................................................     1

     1.1  REGISTERED OFFICE................................................    1
     1.2  OTHER OFFICES....................................................    1

ARTICLE II................................................................     1

     2.1  PLACE OF MEETINGS...............................................     1
     2.2  ANNUAL MEETING..................................................     1
     2.3  SPECIAL MEETING.................................................     2
     2.4  NOTICE OF STOCKHOLDERS' MEETINGS................................     2
     2.5  ADVANCE NOTICE OF STOCKHOLDER NOMINEES AND STOCKHOLDER BUSINESS.     2
     2.6  MANNER OF GIVING NOTICE; AFFIDAVIT OF NOTICE....................     3
     2.7  QUORUM..........................................................     4
     2.8  ADJOURNED MEETING; NOTICE.......................................     4
     2.9  VOTING..........................................................     4
     2.10 WAIVER OF NOTICE................................................     5
     2.11 RECORD DATE FOR STOCKHOLDER NOTICE; VOTING......................     5
     2.12 PROXIES.........................................................     5
     2.13 ORGANIZATION....................................................     5
     2.14 LIST OF STOCKHOLDERS ENTITLED TO VOTE...........................     6

ARTICLE III...............................................................     6

     3.1  POWERS..........................................................     6
     3.2  NUMBER OF DIRECTORS.............................................     6
     3.3  ELECTION AND TERM OF OFFICE OF DIRECTORS........................     6
     3.4  RESIGNATION AND VACANCIES.......................................     7
     3.5  PLACE OF MEETINGS; MEETINGS BY TELEPHONE........................     7
     3.6  REGULAR MEETINGS................................................     7
     3.7  SPECIAL MEETINGS; NOTICE........................................     7
     3.8  QUORUM..........................................................     8
     3.9  WAIVER OF NOTICE................................................     8
     3.10 ADJOURNMENT.....................................................     8
     3.11 NOTICE OF ADJOURNMENT...........................................     8
     3.12 BOARD ACTION BY WRITTEN CONSENT WITHOUT A MEETING...............     8
     3.13 FEES AND COMPENSATION OF DIRECTORS..............................     9
</TABLE>
<PAGE>

                               TABLE OF CONTENTS
                                  (continued)

<TABLE>
<CAPTION>
                                                                        Page
                                                                        ----
<S>                                                                     <C>
      3.14  APPROVAL OF LOANS TO OFFICERS.............................     9

ARTICLE IV............................................................     9

      4.1   COMMITTEES OF DIRECTORS...................................     9
      4.2   MEETINGS AND ACTION OF COMMITTEES.........................    10
      4.3   COMMITTEE MINUTES.........................................    10

ARTICLE V.............................................................    10

      5.1   OFFICERS..................................................    10
      5.2   ELECTION OF OFFICERS......................................    11
      5.3   SUBORDINATE OFFICERS......................................    11
      5.4   REMOVAL AND RESIGNATION OF OFFICERS.......................    11
      5.5   VACANCIES IN OFFICES......................................    11
      5.6   CHAIRMAN OF THE BOARD.....................................    11
      5.7   PRESIDENT.................................................    11
      5.8   VICE PRESIDENTS...........................................    12
      5.9   SECRETARY.................................................    12
      5.10  CHIEF FINANCIAL OFFICER...................................    12

ARTICLE VI............................................................    13

      6.1   INDEMNIFICATION OF DIRECTORS AND OFFICERS.................    13
      6.2   INDEMNIFICATION OF OTHERS.................................    14
      6.3   INSURANCE.................................................    14

ARTICLE VII...........................................................    14

      7.1   MAINTENANCE AND INSPECTION OF RECORDS.....................    14
      7.2   INSPECTION BY DIRECTORS...................................    15
      7.3   ANNUAL STATEMENT TO STOCKHOLDERS..........................    15
      7.4   REPRESENTATION OF SHARES OF OTHER CORPORATIONS............    15
      7.5   CERTIFICATION AND INSPECTION OF BYLAWS....................    15

ARTICLE VIII..........................................................    15

      8.1   RECORD DATE FOR PURPOSES OTHER THAN NOTICE AND VOTING.....    15
      8.2   CHECKS; DRAFTS; EVIDENCES OF INDEBTEDNESS.................    16
      8.3   CORPORATE CONTRACTS AND INSTRUMENTS:  HOW EXECUTED........    16
      8.4   STOCK CERTIFICATES; TRANSFER; PARTLY PAID SHARES..........    16
      8.5   SPECIAL DESIGNATION ON CERTIFICATES.......................    17
      8.6   LOST CERTIFICATES.........................................    17
      8.7   TRANSFER AGENTS AND REGISTRARS............................    17
      8.8   CONSTRUCTION; DEFINITIONS.................................    17

ARTICLE IX............................................................    18
</TABLE>

                                     -ii-
<PAGE>

                                                                       EXHIBIT C

                                    BYLAWS
                                    ------

                                      OF
                                      --

                        CENTILLIUM COMMUNICATIONS, INC.
                        -------------------------------

                            (a Delaware Corporation)

                                   ARTICLE I

                               CORPORATE OFFICES
                               -----------------

1.1  REGISTERED OFFICE
     -----------------

     The registered office of the corporation shall be fixed in the certificate
of incorporation of the corporation.

1.2  OTHER OFFICES
     -------------

     The board of directors may at any time establish branch or subordinate
offices at any place or places where the corporation is qualified to do
business.

                                  ARTICLE II

                           MEETINGS OF STOCKHOLDERS
                           ------------------------

2.1  PLACE OF MEETINGS
     -----------------

     Meetings of stockholders shall be held at any place within or outside the
State of Delaware designated by the board of directors.  In the absence of any
such designation, stockholders' meetings shall be held at the principal
executive office of the corporation.

2.2  ANNUAL MEETING
     --------------

     The annual meeting of stockholders shall be held each year on a date and at
a time designated by the board of directors.  In the absence of such
designation, the annual meeting of stockholders shall be held on the third
Tuesday of May in each year at 10:00 a.m.  However, if such day falls on a legal
holiday, then the meeting shall be held at the same time and place on the next
succeeding full business day.  At the meeting, directors shall be elected, and
any other proper business may be transacted.
<PAGE>

2.3  SPECIAL MEETING
     ---------------

     A special meeting of the stockholders may be called at any time by the
board of directors, or by the chairman of the board, by the president, or by one
or more stockholders holding shares in the aggregate entitled to cast not less
than fifty percent (50%) of the votes at that meeting.

     If a special meeting is called by any person or persons other than the
board of directors or the president or the chairman of the board, then the
request shall be in writing, specifying the time of such meeting and the general
nature of the business proposed to be transacted, and shall be delivered
personally or sent by registered mail or by telegraphic or other facsimile
transmission to the chairman of the board, the president, any vice president or
the secretary of the corporation.  The officer receiving the request shall cause
notice to be promptly given to the shareholders entitled to vote, in accordance
with the provisions of Sections 2.4 and 2.5 of these bylaws, that a meeting will
be held at the time requested by the person or persons calling the meeting, so
long as that time is not less than thirty-five (35) nor more than sixty (60)
days after the receipt of the request.  If the notice is not given within twenty
(20) days after receipt of the request, then the person or persons requesting
the meeting may give the notice.  Nothing contained in this paragraph of this
Section 2.3 shall be construed as limiting, fixing or affecting the time when a
meeting of shareholders called by action of the board of directors may be held.

2.4  NOTICE OF STOCKHOLDERS' MEETINGS
     --------------------------------

     All notices of meetings of stockholders shall be sent or otherwise given in
accordance with Section 2.6 of these bylaws not less than ten (10) nor more than
sixty (60) days before the date of the meeting.  The notice shall specify the
place, date and hour of the meeting and (i) in the case of a special meeting,
the purpose or purposes for which the meeting is called (no business other than
that specified in the notice may be transacted) or (ii) in the case of the
annual meeting, those matters which the board of directors, at the time of
giving the notice, intends to present for action by the stockholders (but any
proper matter may be presented at the meeting for such action).  The notice of
any meeting at which directors are to be elected shall include the name of any
nominee or nominees who, at the time of the notice, the board intends to present
for election.

2.5  ADVANCE NOTICE OF STOCKHOLDER NOMINEES AND STOCKHOLDER BUSINESS
     ---------------------------------------------------------------

     Subject to the rights of holders of any class or series of stock having a
preference over the Common Stock as to dividends or upon liquidation,

     (a)  nominations for the election of directors, and

     (b)  business proposed to be brought before any stockholder meeting

may be made by the board of directors or proxy committee appointed by the board
of directors or by any stockholder entitled to vote in the election of directors
generally if such nomination or business proposed is otherwise proper business
before such meeting.  However, any such stockholder may nominate one or more
persons for election as directors at a meeting or propose business to be

                                      -2-
<PAGE>

brought before a meeting, or both, only if such stockholder has given timely
notice to the secretary of the corporation in proper written form of their
intent to make such nomination or nominations or to propose such business. To be
timely, such stockholder's notice must be delivered to or mailed and received at
the principal executive offices of the corporation not less than one hundred
twenty (120) calendar days in advance of the date of the corporation's proxy
statement released to stockholders in connection with the previous year's annual
meeting of stockholders; provided, however, that in the event that no annual
meeting was held in the previous year or the date of the annual meeting has been
changed by more than thirty (30) days from the date contemplated at the time of
the previous year's proxy statement, notice by the stockholder to be timely must
be so received a reasonable time before the solicitation is made. To be in
proper form, a stockholder's notice to the secretary shall set forth:

                         (i)    the name and address of the stockholder who
intends to make the nominations or propose the business and, as the case may be,
of the person or persons to be nominated or of the business to be proposed;

                         (ii)   a representation that the stockholder is a
holder of record of stock of the corporation entitled to vote at such meeting
and, if applicable, intends to appear in person or by proxy at the meeting to
nominate the person or persons specified in the notice;

                         (iii)  if applicable, a description of all arrangements
or understandings between the stockholder and each nominee and any other person
or persons (naming such person or persons) pursuant to which the nomination or
nominations are to be made by the stockholder;

                         (iv)   such other information regarding each nominee or
each matter of business to be proposed by such stockholder as would be required
to be included in a proxy statement filed pursuant to the proxy rules of the
Securities and Exchange Commission had the nominee been nominated, or intended
to be nominated, or the matter been proposed, or intended to be proposed by the
board of directors; and

                         (v)    if applicable, the consent of each nominee to
serve as director of the corporation if so elected.

     The chairman of the meeting shall refuse to acknowledge the nomination of
any person or the proposal of any business not made in compliance with the
foregoing procedure.

2.6  MANNER OF GIVING NOTICE; AFFIDAVIT OF  NOTICE

     Written notice of any meeting of stockholders shall be given either
personally or by first-class mail or by telegraphic or other written
communication.  Notices not personally delivered shall be sent charges prepaid
and shall be addressed to the stockholder at the address of that stockholder
appearing on the books of the corporation or given by the stockholder to the
corporation for the purpose of notice.  Notice shall be deemed to have been
given at the time when delivered personally or deposited in the mail or sent by
telegram or other means of written communication.

                                      -3-
<PAGE>

     An affidavit of the mailing or other means of giving any notice of any
stockholders' meeting, executed by the secretary, assistant secretary or any
transfer agent of the corporation giving the notice, shall be prima facie
evidence of the giving of such notice.

2.7  QUORUM
     ------

     The holders of a majority in voting power of the stock issued and
outstanding and entitled to vote thereat, present in person or represented by
proxy, shall constitute a quorum at all meetings of the stockholders for the
transaction of business except as otherwise provided by statute or by the
certificate of incorporation.  If, however, such quorum is not present or
represented at any meeting of the stockholders, then either (i) the chairman of
the meeting or (ii) the stockholders entitled to vote thereat, present in person
or represented by proxy, shall have power to adjourn the meeting in accordance
with Section 2.7 of these bylaws.

     When a quorum is present at any meeting, the vote of the holders of a
majority of the stock having voting power present in person or represented by
proxy shall decide any question brought before such meeting, unless the question
is one upon which, by express provision of the laws of the State of Delaware or
of the certificate of incorporation or these bylaws, a different vote is
required, in which case such express provision shall govern and control the
decision of the question.

     If a quorum be initially present, the stockholders may continue to transact
business until adjournment, notwithstanding the withdrawal of enough
stockholders to leave less than a quorum, if any action taken is approved by a
majority of the stockholders initially constituting the quorum.

2.8  ADJOURNED MEETING; NOTICE
     -------------------------

     When a meeting is adjourned to another time and place, unless these bylaws
otherwise require, notice need not be given of the adjourned meeting if the time
and place thereof are announced at the meeting at which the adjournment is
taken.  At the adjourned meeting the corporation may transact any business that
might have been transacted at the original meeting.  If the adjournment is for
more than thirty (30) days, or if after the adjournment a new record date is
fixed for the adjourned meeting, a notice of the adjourned meeting shall be
given to each stockholder of record entitled to vote at the meeting.

2.9  VOTING
     ------

     The stockholders entitled to vote at any meeting of stockholders shall be
determined in accordance with the provisions of Section 2.11 of these bylaws,
subject to the provisions of Sections 217 and 218 of the General Corporation Law
of Delaware (relating to voting rights of fiduciaries, pledgors and joint
owners, and to voting trusts and other voting agreements).

     Except as may be otherwise provided in the certificate of incorporation or
these bylaws, each stockholder shall be entitled to one vote for each share of
capital stock held by such stockholder with respect to any matter submitted to a
vote of the stockholders and stockholders shall not be entitled to cumulate
their votes in the election of directors.

                                      -4-
<PAGE>

2.10  WAIVER OF NOTICE
      ----------------

      Whenever notice is required to be given under any provision of the General
Corporation Law of Delaware or of the certificate of incorporation or these
bylaws, a written waiver thereof, signed by the person entitled to notice,
whether before or after the time stated therein, shall be deemed equivalent to
notice.  Attendance of a person at a meeting shall constitute a waiver of notice
of such meeting, except when the person attends a meeting for the express
purpose of objecting, at the beginning of the meeting, to the transaction of any
business because the meeting is not lawfully called or convened.  Neither the
business to be transacted at, nor the purpose of, any regular or special meeting
of the stockholders need be specified in any written waiver of notice unless so
required by the certificate of incorporation or these bylaws.

2.11  RECORD DATE FOR STOCKHOLDER NOTICE; VOTING
      ------------------------------------------

      For purposes of determining the stockholders entitled to notice of any
meeting or to vote thereat, the board of directors may fix, in advance, a record
date, which shall not precede the date upon which the resolution fixing the
record date is adopted by the board of directors and which shall not be more
than sixty (60) days nor less than ten (10) days before the date of any such
meeting, and in such event only stockholders of record on the date so fixed are
entitled to notice and to vote, notwithstanding any transfer of any shares on
the books of the corporation after the record date.

      If the board of directors does not so fix a record date, the record date
for determining stockholders entitled to notice of or to vote at a meeting of
stockholders shall be at the close of business on the business day next
preceding the day on which notice is given, or, if notice is waived, at the
close of business on the business day next preceding the day on which the
meeting is held.

      A determination of stockholders of record entitled to notice of or to vote
at a meeting of stockholders shall apply to any adjournment of the meeting
unless the board of directors fixes a new record date for the adjourned meeting,
but the board of directors shall fix a new record date if the meeting is
adjourned for more than thirty (30) days from the date set for the original
meeting.

      The record date for any other purpose shall be as provided in Section 8.1
of these bylaws.

2.12  PROXIES
      -------

      Every person entitled to vote for directors, or on any other matter, shall
have the right to do so either in person or by one or more agents authorized by
a written proxy signed by the person and filed with the secretary of the
corporation, but no such proxy shall be voted or acted upon after three (3)
years from its date unless the proxy provides for a longer period.  A proxy
shall be deemed signed if the stockholder's name is placed on the proxy (whether
by manual signature, typewriting, telegraphic transmission, telefacsimile or
otherwise) by the stockholder or the stockholder's attorney-in-fact.  The
revocability of a proxy that states on its face that it is irrevocable shall be
governed by the provisions of Section 212(e) of the General Corporation Law of
Delaware.

2.13  ORGANIZATION
      ------------

                                      -5-
<PAGE>

      The president, or in the absence of the president, the chairman of the
board, or, in the absence of the president and the chairman of the board, one of
the corporation's vice presidents, shall call the meeting of the stockholders to
order, and shall act as chairman of the meeting.  In the absence of the
president, the chairman of the board, and all of the vice presidents, the
stockholders shall appoint a chairman for such meeting.  The chairman of any
meeting of stockholders shall determine the order of business and the procedures
at the meeting, including such matters as the regulation of the manner of voting
and the conduct of business.  The secretary of the corporation shall act as
secretary of all meetings of the stockholders, but in the absence of the
secretary at any meeting of the stockholders, the chairman of the meeting may
appoint any person to act as secretary of the meeting.

2.14  LIST OF STOCKHOLDERS ENTITLED TO VOTE
      -------------------------------------

      The officer who has charge of the stock ledger of the corporation shall
prepare and make, at least ten (10) days before every meeting of stockholders, a
complete list of the stockholders entitled to vote at the meeting, arranged in
alphabetical order, and showing the address of each stockholder and the number
of shares registered in the name of each stockholder.  Such list shall be open
to the examination of any stockholder, for any purpose germane to the meeting,
during ordinary business hours, for a period of at least ten (10) days prior to
the meeting, either at a place within the city where the meeting is to be held,
which place shall be specified in the notice of the meeting, or, if not so
specified, at the place where the meeting is to be held.  The list shall also be
produced and kept at the time and place of the meeting during the whole time
thereof, and may be inspected by any stockholder who is present.

                                  ARTICLE III

                                   DIRECTORS
                                   ---------
3.1   POWERS
      ------

      Subject to the provisions of the General Corporation Law of Delaware and
any limitations in the certificate of incorporation and these bylaws relating to
action required to be approved by the stockholders or by the outstanding shares,
the business and affairs of the corporation shall be managed and all corporate
powers shall be exercised by or under the direction of the board of directors.

3.2   NUMBER OF DIRECTORS
      -------------------

      The board of directors shall consist of no less than five and no more than
seven members.  The board of directors may increase or decrease the number of
directors constituting the board of directors upon the approval of a majority of
the directors then in office.  The number of directors so determined shall be
the authorized number of directors of the corporation.  No reduction of the
authorized number of directors shall have the effect of removing any director
before that director's term of office expires.

3.3   ELECTION AND TERM OF OFFICE OF DIRECTORS
      ----------------------------------------

                                      -6-
<PAGE>

     Except as provided in Section 3.4 of these bylaws, directors shall be
elected at each annual meeting of stockholders to hold office until the next
annual meeting. Each director, including a director elected or appointed to fill
a vacancy, shall hold office until the expiration of the term for which elected
and until a successor has been elected and qualified.

3.4  RESIGNATION AND VACANCIES
     -------------------------

     Any director may resign effective on giving written notice to the chairman
of the board, the president, the secretary or the board of directors, unless the
notice specifies a later time for that resignation to become effective.  If the
resignation of a director is effective at a future time, the board of directors
may elect a successor to take office when the resignation becomes effective.

     All vacancies in the board of directors may be filled by a majority of the
remaining directors, even if less than a quorum, or by a sole remaining
director; provided, that whenever the holders of any class or classes of stock
or series thereof are entitled to elect one or more directors by the provisions
of the certificate of incorporation, vacancies and newly created directorships
of such class or classes or series may be filled by a majority of the directors
elected by such class or classes or series thereof then in office, or by a sole
remaining director so elected.

3.5  PLACE OF MEETINGS; MEETINGS BY TELEPHONE
     ----------------------------------------

     Regular meetings of the board of directors may be held at any place within
or outside the State of Delaware that has been designated from time to time by
resolution of the board.  In the absence of such a designation, regular meetings
shall be held at the principal executive office of the corporation.  Special
meetings of the board may be held at any place within or outside the State of
Delaware that has been designated in the notice of the meeting or, if not stated
in the notice or if there is no notice, at the principal executive office of the
corporation.

     Any meeting, regular or special, may be held by conference telephone or
similar communication equipment, so long as all directors participating in the
meeting can hear one another; and all such directors shall be deemed to be
present in person at the meeting.

3.6  REGULAR MEETINGS
     ----------------

     Regular meetings of the board of directors may be held without notice if
the times of such meetings are fixed by the board of directors.  If any regular
meeting day shall fall on a legal holiday, then the meeting shall be held next
succeeding full business day.

3.7  SPECIAL MEETINGS; NOTICE
     ------------------------

     Special meetings of the board of directors for any purpose or purposes may
be called at any time by the chairman of the board, the president, any vice
president, the secretary or any two directors.

     Notice of the time and place of special meetings shall be delivered
personally or by telephone to each director or sent by first-class mail or
telegram, charges prepaid, addressed to each director at

                                      -7-
<PAGE>

that director's address as it is shown on the records of the corporation. If the
notice is mailed, it shall be deposited in the United States mail at least four
(4) days before the time of the holding of the meeting. If the notice is
delivered personally or by telephone or telegram, it shall be delivered
personally or by telephone or to the telegraph company at least forty-eight (48)
hours before the time of the holding of the meeting. Any oral notice given
personally or by telephone may be communicated either to the director or to a
person at the office of the director who the person giving the notice has reason
to believe will promptly communicate it to the director. The notice need not
specify the purpose or the place of the meeting, if the meeting is to be held at
the principal executive office of the corporation.

3.8   QUORUM
      ------

      A majority of the authorized number of directors shall constitute a quorum
for the transaction of business, except to adjourn as provided in Section 3.10
of these bylaws.  Every act or decision done or made by a majority of the
directors present at a duly held meeting at which a quorum is present shall be
regarded as the act of the board of directors, subject to the provisions of the
certificate of incorporation and other applicable law.

      A meeting at which a quorum is initially present may continue to transact
business notwithstanding the withdrawal of directors, if any action taken is
approved by at least a majority of the required quorum for that meeting.

3.9   WAIVER OF NOTICE
      ----------------

      Notice of a meeting need not be given to any director (i) who signs a
waiver of notice or a consent to holding the meeting or an approval of the
minutes thereof, whether before or after the meeting, or (ii) who attends the
meeting without protesting, prior thereto or at its commencement, the lack of
notice to such directors.  All such waivers, consents, and approvals shall be
filed with the corporate records or made part of the minutes of the meeting.  A
waiver of notice need not specify the purpose of any regular or special meeting
of the board of directors.

3.10  ADJOURNMENT
      -----------

      A majority of the directors present, whether or not constituting a quorum,
may adjourn any meeting to another time and place.

3.11  NOTICE OF ADJOURNMENT
      ---------------------

      Notice of the time and place of holding an adjourned meeting need not be
given unless the meeting is adjourned for more than twenty-four (24) hours.  If
the meeting is adjourned for more than twenty-four (24) hours, then notice of
the time and place of the adjourned meeting shall be given before the adjourned
meeting takes place, in the manner specified in Section 3.7 of these bylaws, to
the directors who were not present at the time of the adjournment.

3.12  BOARD ACTION BY WRITTEN CONSENT WITHOUT A MEETING
      -------------------------------------------------

                                      -8-
<PAGE>

      Any action required or permitted to be taken by the board of directors may
be taken without a meeting, provided that all members of the board individually
or collectively consent in writing to that action.  Such action by written
consent shall have the same force and effect as a unanimous vote of the board of
directors. Such written consent and any counterparts thereof shall be filed with
the minutes of the proceedings of the board.

3.13  FEES AND COMPENSATION OF DIRECTORS
      ----------------------------------

      Directors and members of committees may receive such compensation, if any,
for their services and such reimbursement of expenses as may be fixed or
determined by resolution of the board of directors.  This Section 3.13 shall not
be construed to preclude any director from serving the corporation in any other
capacity as an officer, agent, employee or otherwise and receiving compensation
for those services.

3.14  APPROVAL OF LOANS TO OFFICERS
      -----------------------------

      The corporation may lend money to, or guarantee any obligation of, or
otherwise assist any officer or other employee of the corporation or any of its
subsidiaries, including any officer or employee who is a director of the
corporation or any of its subsidiaries, whenever, in the judgment of the
directors, such loan, guaranty or assistance may reasonably be expected to
benefit the corporation.  The loan, guaranty or other assistance may be with or
without interest and may be unsecured, or secured in such manner as the board of
directors shall approve, including, without limitation, a pledge of shares of
stock of the corporation.  Nothing contained in this section shall be deemed to
deny, limit or restrict the powers of guaranty or warranty of the corporation at
common law or under any statute.

                                  ARTICLE IV

                                  COMMITTEES
                                  ----------
4.1   COMMITTEES OF DIRECTORS
      -----------------------

      The board of directors may, by resolution adopted by a majority of the
authorized number of directors, designate one (1) or more committees, each
consisting of two or more directors, to serve at the pleasure of the board.  The
board may designate one (1) or more directors as alternate members of any
committee, who may replace any absent member at any meeting of the committee.
The appointment of members or alternate members of a committee requires the vote
of a majority of the authorized number of directors.  Any committee, to the
extent provided in the resolution of the board, shall have and may exercise all
the powers and authority of the board, but no such committee shall have the
power of authority to:

     (a)  amend the certificate of incorporation (except that a committee may,
to the extent authorized in the resolution or resolutions providing for the
issuance of shares of stock adopted by the board of directors as provided in
Section 151(a) of the General Corporation Law of Delaware, fix the designations
and any of the preferences or rights of such shares relating to dividends,
redemption, dissolution, any distribution of assets of the corporation or the
conversion into, or the

                                      -9-
<PAGE>

exchange of such shares for, shares of any other class or classes or any other
series of the same or any other class or classes of stock of the corporation);

     (b)  adopt an agreement of merger or consolidation under Sections 251 or
252 of the General Corporation Law of Delaware;

     (c)  recommend to the stockholders the sale, lease or exchange of all or
substantially all of the corporation's property and assets;

     (d)  recommend to the stockholders a dissolution of the corporation or a
revocation of a dissolution; or

     (e)  amend the bylaws of the corporation; and, unless the board resolution
establishing the committee, the bylaws or the certificate of incorporation
expressly so provide, no such committee shall have the power or authority to
declare a dividend, to authorize the issuance of stock, or to adopt a
certificate of ownership and merger pursuant to Section 253 of the General
Corporation Law of Delaware.

4.2  MEETINGS AND ACTION OF COMMITTEES
     ---------------------------------

     Meetings and actions of committees shall be governed by, and held and taken
in accordance with, the provisions of Article III of these bylaws, Section 3.5
(place of meetings), Section 3.6 (regular meetings), Section 3.7 (special
meetings and notice), Section 3.8 (quorum), Section 3.9 (waiver of notice),
Section 3.10 (adjournment), Section 3.11 (notice of adjournment), and Section
3.12 (action without meeting), with such changes in the context of those bylaws
as are necessary to substitute the committee and its members for the board of
directors and its members; provided, however, that the time of regular meetings
of committees may be determined either by resolution of the board of directors
or by resolution of the committee, that special meetings of committees may also
be called by resolution of the board of directors, and that notice of special
meetings of committees shall also be given to all alternate members, who shall
have the right to attend all meetings of the committee.  The board of directors
may adopt rules for the government of any committee not inconsistent with the
provisions of these bylaws.

4.3  COMMITTEE MINUTES
     -----------------

     Each committee shall keep regular minutes of its meetings and report the
same to the board of directors when required.

                                   ARTICLE V

                                   OFFICERS
                                   --------

5.1  OFFICERS
     --------

     The officers of the corporation shall be a president, a secretary, and a
chief financial officer.  The corporation may also have, at the discretion of
the board of directors, a chairman of the board, one or more vice presidents,
one or more assistant secretaries, one or more assistant treasurers, and

                                      -10-
<PAGE>

such other officers as may be appointed in accordance with the provisions of
Section 5.3 of these bylaws. Any number of offices may be held by the same
person.

5.2  ELECTION OF OFFICERS
     --------------------

     The officers of the corporation, except such officers as may be appointed
in accordance with the provisions of Section 5.3 or Section 5.5 of these bylaws,
shall be chosen by the board, subject to the rights, if any, of an officer under
any contract of employment.

5.3  SUBORDINATE OFFICERS
     --------------------

     The board of directors may appoint, or may empower the president to
appoint, such other officers as the business of the corporation may require,
each of whom shall hold office for such period, have such authority, and perform
such duties as are provided in these bylaws or as the board of directors may
from time to time determine.

5.4  REMOVAL AND RESIGNATION OF OFFICERS
     -----------------------------------

     Subject to the rights, if any, of an officer under any contract of
employment, any officer may be removed, either with or without cause, by the
board of directors at any regular or special meeting of the board or, except in
case of an officer chosen by the board of directors, by any officer upon whom
such power of removal may be conferred by the board of directors.

     Any officer may resign at any time by giving written notice to the
corporation.  Any resignation shall take effect at the date of the receipt of
that notice or at any later time specified in that notice; and, unless otherwise
specified in that notice, the acceptance of the resignation shall not be
necessary to make it effective.  Any resignation is without prejudice to the
rights, if any, of the corporation under any contract to which the officer is a
party.

5.5  VACANCIES IN OFFICES
     --------------------

     A vacancy in any office because of death, resignation, removal,
disqualification or any other cause shall be filled in the manner prescribed in
these bylaws for regular appointments to that office.

5.6  CHAIRMAN OF THE BOARD
     ---------------------

     The chairman of the board, if such an officer be elected, shall, if
present, preside at meetings of the board of directors and exercise and perform
such other powers and duties as may from time to time be assigned to him by the
board of directors or as may be prescribed by these bylaws.  If there is no
president, then the chairman of the board shall also be the chief executive
officer of the corporation and shall have the powers and duties prescribed in
Section 5.7 of these bylaws.

5.7  PRESIDENT
     ---------

     Subject to such supervisory powers, if any, as may be given by the board of
directors to the chairman of the board, if there be such an officer, the
president shall be the chief executive officer of the corporation and shall,
subject to the control of the board of directors, have general supervision,

                                      -11-
<PAGE>

direction, and control of the business and the officers of the corporation.  He
shall preside at all meetings of the stockholders and, in the absence or
nonexistence of a chairman of the board, at all meetings of the board of
directors.  He shall have the general powers and duties of management usually
vested in the office of president of a corporation, and shall have such other
powers and duties as may be prescribed by the board of directors or these
bylaws.

5.8  VICE PRESIDENTS
     ---------------

     In the absence or disability of the president, the vice presidents, if any,
in order of their rank as fixed by the board of directors or, if not ranked, a
vice president designated by the board of directors, shall perform all the
duties of the president and when so acting shall have all the powers of, and be
subject to all the restrictions upon, the president.  The vice presidents shall
have such other powers and perform such other duties as from time to time may be
prescribed for them respectively by the board of directors, these bylaws, the
president or the chairman of the board.

5.9  SECRETARY
     ---------

     The secretary shall keep or cause to be kept, at the principal executive
office of the corporation or such other place as the board of directors may
direct, a book of minutes of all meetings and actions of directors, committees
of directors and stockholders.  The minutes shall show the time and place of
each meeting, whether regular or special (and, if special, how authorized and
the notice given), the names of those present at directors' meetings or
committee meetings, the number of shares present or represented at stockholders'
meetings, and the proceedings thereof.

     The secretary shall keep, or cause to be kept, at the principal executive
office of the corporation or at the office of the corporation's transfer agent
or registrar, as determined by resolution of the board of directors, a share
register, or a duplicate share register, showing the names of all stockholders
and their addresses, the number and classes of shares held by each, the number
and date of certificates evidencing such shares, and the number and date of
cancellation of every certificate surrendered for cancellation.

     The secretary shall give, or cause to be given, notice of all meetings of
the stockholders and of the board of directors required to be given by law or by
these bylaws.  He shall keep the seal of the corporation, if one be adopted, in
safe custody and shall have such other powers and perform such other duties as
may be prescribed by the board of directors or by these bylaws.

5.10 CHIEF FINANCIAL OFFICER
     -----------------------

     The chief financial officer shall keep and maintain, or cause to be kept
and maintained, adequate and correct books and records of accounts of the
properties and business transactions of the corporation, including accounts of
its assets, liabilities, receipts, disbursements, gains, losses, capital,
retained earnings, and shares.  The books of account shall at all reasonable
times be open to inspection by any director.

     The chief financial officer shall deposit all money and other valuables in
the name and to the credit of the corporation with such depositaries as may be
designated by the board of directors. He

                                      -12-
<PAGE>

shall disburse the funds of the corporation as may be ordered by the board of
directors, shall render to the president and directors, whenever they request
it, an account of all of his transactions as chief financial officer and of the
financial condition of the corporation, and shall have such other powers and
perform such other duties as may be prescribed by the board of directors or
these bylaws.

                                  ARTICLE VI

              INDEMNIFICATION OF DIRECTORS, OFFICERS, EMPLOYEES,
              --------------------------------------------------
                               AND OTHER AGENTS
                               ----------------

6.1  INDEMNIFICATION OF DIRECTORS AND OFFICERS
     -----------------------------------------

     The corporation shall, to the maximum extent and in the manner permitted by
the General Corporation Law of Delaware as the same now exists or may hereafter
be amended, indemnify any person against expenses (including attorneys' fees),
judgments, fines, and amounts paid in settlement actually and reasonably
incurred in connection with any threatened, pending or completed action, suit,
or proceeding in which such person was or is a party or is threatened to be made
a party by reason of the fact that such person is or was a director or officer
of the corporation.  For purposes of this Section 6.1, a "director" or "officer"
of the corporation shall mean any person (i) who is or was a director or officer
of the corporation, (ii) who is or was serving at the request of the corporation
as a director or officer of another corporation, partnership, joint venture,
trust or other enterprise, or (iii) who was a director or officer of a
corporation which was a predecessor corporation of the corporation or of another
enterprise at the request of such predecessor corporation.

     The corporation shall be required to indemnify a director or officer in
connection with an action, suit, or proceeding (or part thereof) initiated by
such director or officer only if the initiation of such action, suit, or
proceeding (or part thereof) by the director or officer was authorized by the
Board of Directors of the corporation.

     The corporation shall pay the expenses (including attorney's fees) incurred
by a director or officer of the corporation entitled to indemnification
hereunder in defending any action, suit or proceeding referred to in this
Section 6.1 in advance of its final disposition; provided, however, that payment
of expenses incurred by a director or officer of the corporation in advance of
the final disposition of such action, suit or proceeding shall be made only upon
receipt of an undertaking by the director or officer to repay all amounts
advanced if it should ultimately be determined that the director of officer is
not entitled to be indemnified under this Section 6.1 or otherwise.

     The rights conferred on any person by this Article shall not be exclusive
of any other rights which such person may have or hereafter acquire under any
statute, provision of the corporation's Certificate of Incorporation, these
bylaws, agreement, vote of the stockholders or disinterested directors or
otherwise.

     Any repeal or modification of the foregoing provisions of this Article
shall not adversely affect any right or protection hereunder of any person in
respect of any act or omission occurring prior to the time of such repeal or
modification.

                                      -13-
<PAGE>

6.2  INDEMNIFICATION OF OTHERS
     -------------------------

     The corporation shall have the power, to the maximum extent and in the
manner permitted by the General Corporation Law of Delaware as the same now
exists or may hereafter be amended, to indemnify any person (other than
directors and officers) against expenses (including attorneys' fees), judgments,
fines, and amounts paid in settlement actually and reasonably incurred in
connection with any threatened, pending or completed action, suit, or
proceeding, in which such person was or is a party or is threatened to be made a
party by reason of the fact that such person is or was an employee or agent of
the corporation.  For purposes of this Section 6.2, an "employee" or "agent" of
the corporation (other than a director or officer) shall mean any person (i) who
is or was an employee or agent of the corporation, (ii) who is or was serving at
the request of the corporation as an employee or agent of another corporation,
partnership, joint venture, trust or other enterprise, or (iii) who was an
employee or agent of a corporation which was a predecessor corporation of the
corporation or of another enterprise at the request of such predecessor
corporation.

6.3  INSURANCE
     ---------

     The corporation may purchase and maintain insurance on behalf of any person
who is or was a director, officer, employee or agent of the corporation, or is
or was serving at the request of the corporation as a director, officer,
employee or agent of another corporation, partnership, joint venture, trust or
other enterprise against any liability asserted against him or her and incurred
by him or her in any such capacity, or arising out of his or her status as such,
whether or not the corporation would have the power to indemnify him or her
against such liability under the provisions of the General Corporation Law of
Delaware.

                                  ARTICLE VII

                              RECORDS AND REPORTS
                              -------------------

7.1  MAINTENANCE AND INSPECTION OF RECORDS
     -------------------------------------

     The corporation shall, either at its principal executive office or at such
place or places as designated by the board of directors, keep a record of its
stockholders listing their names and addresses and the number and class of
shares held by each stockholder, a copy of these bylaws as amended to date,
accounting books and other records of its business and properties.

     Any stockholder of record, in person or by attorney or other agent, shall,
upon written demand under oath stating the purpose thereof, have the right
during the usual hours for business to inspect for any proper purpose the
corporation's stock ledger, a list of its stockholders, and its other books and
records and to make copies or extracts therefrom.  A proper purpose shall mean a
purpose reasonably related to such person's interest as a stockholder.  In every
instance where an attorney or other agent is the person who seeks the right to
inspection, the demand under oath shall be accompanied by a power of attorney or
such other writing that authorizes the attorney or other agent to so act on
behalf of the stockholder. The demand under oath shall be directed to the
corporation at its registered office in Delaware or at its principal place of
business.

                                      -14-
<PAGE>

7.2  INSPECTION BY DIRECTORS
     -----------------------

     Any director shall have the right to examine (and to make copies of) the
corporation's stock ledger, a list of its stockholders and its other books and
records for a purpose reasonably related to his or her position as a director.

7.3  ANNUAL STATEMENT TO STOCKHOLDERS
     --------------------------------

     The board of directors shall present at each annual meeting, and at any
special meeting of the stockholders when called for by vote of the stockholders,
a full and clear statement of the business and condition of the corporation.

7.4  REPRESENTATION OF SHARES OF OTHER CORPORATIONS
     ----------------------------------------------

     The chairman of the board, if any, the president, any vice president, the
chief financial officer, the secretary or any assistant secretary of this
corporation, or any other person authorized by the board of directors or the
president or a vice president, is authorized to vote, represent and exercise on
behalf of this corporation all rights incident to any and all shares of the
stock of any other corporation or corporations standing in the name of this
corporation.  The authority herein granted may be exercised either by such
person directly or by any other person authorized to do so by proxy or power of
attorney duly executed by such person having the authority.

7.5  CERTIFICATION AND INSPECTION OF BYLAWS
     --------------------------------------

     The original or a copy of these bylaws, as amended or otherwise altered to
date, certified by the secretary, shall be kept at the corporation's principal
executive office and shall be open to inspection by the stockholders of the
corporation, at all reasonable times during office hours.

                                 ARTICLE VIII

                                GENERAL MATTERS
                                ---------------

8.1  RECORD DATE FOR PURPOSES OTHER THAN NOTICE AND VOTING
     -----------------------------------------------------

     For purposes of determining the stockholders entitled to receive payment of
any dividend or other distribution or allotment of any rights or the
stockholders entitled to exercise any rights in respect of any other lawful
action, the board of directors may fix, in advance, a record date, which shall
not be more than sixty (60) days before any such action.  In that case, only
stockholders of record at the close of business on the date so fixed are
entitled to receive the dividend, distribution or allotment of rights, or to
exercise such rights, as the case may be, notwithstanding any transfer of any
shares on the books of the corporation after the record date so fixed, except as
otherwise provided in the General Corporation Law of Delaware.

     If the board of directors does not so fix a record date, then the record
date for determining stockholders for any such purpose shall be at the close of
business on the day on which the board adopts the applicable resolution.

                                      -15-
<PAGE>

8.2  CHECKS; DRAFTS; EVIDENCES OF INDEBTEDNESS
     -----------------------------------------

     From time to time, the board of directors shall determine by resolution
which person or persons may sign or endorse all checks, drafts, other orders for
payment of money, notes or other evidences of indebtedness that are issued in
the name of or payable to the corporation, and only the persons so authorized
shall sign or endorse those instruments.

8.3  CORPORATE CONTRACTS AND INSTRUMENTS:  HOW EXECUTED
     --------------------------------------------------

     The board of directors, except as otherwise provided in these bylaws, may
authorize any officer or officers, or agent or agents, to enter into any
contract or execute any instrument in the name of and on behalf of the
corporation; such authority may be general or confined to specific instances.
Unless so authorized or ratified by the board of directors or within the agency
power of an officer, no officer, agent or employee shall have any power or
authority to bind the corporation by any contract or engagement or to pledge its
credit or to render it liable for any purpose or for any amount.

8.4  STOCK CERTIFICATES; TRANSFER; PARTLY PAID SHARES
     ------------------------------------------------

     The shares of the corporation shall be represented by certificates,
provided that the board of directors of the corporation may provide by
resolution or resolutions that some or all of any or all classes or series of
its stock shall be uncertificated shares.  Any such resolution shall not apply
to shares represented by a certificate until such certificate is surrendered to
the corporation.  Notwithstanding the adoption of such a resolution by the board
of directors, every holder of stock represented by certificates and, upon
request, every holder of uncertificated shares, shall be entitled to have a
certificate signed by, or in the name of the corporation by, the chairman or
vice-chairman of the board of directors, or the president or vice-president, and
by the treasurer or an assistant treasurer, or the secretary or an assistant
secretary of such corporation representing the number of shares registered in
certificate form.  Any or all of the signatures on the certificate may be a
facsimile.  In case any officer, transfer agent or registrar who has signed or
whose facsimile signature has been placed upon a certificate has ceased to be
such officer, transfer agent or registrar before such certificate is issued, it
may be issued by the corporation with the same effect as if he or she were such
officer, transfer agent or registrar at the date of issue.

     Certificates for shares shall be of such form and device as the board of
directors may designate and shall state the name of the record holder of the
shares represented thereby; its number; date of issuance; the number of shares
for which it is issued; a summary statement or reference to the powers,
designations, preferences or other special rights of such stock and the
qualifications, limitations or restrictions of such preferences and/or rights,
if any; a statement or summary of liens, if any; a conspicuous notice of
restrictions upon transfer or registration of transfer, if any; a statement as
to any applicable voting trust agreement; if the shares be assessable, or, if
assessments are collectible by personal action, a plain statement of such facts.

     Upon surrender to the secretary or transfer agent of the corporation of a
certificate for shares duly endorsed or accompanied by proper evidence of
succession, assignment or authority to transfer,

                                      -16-
<PAGE>

it shall be the duty of the corporation to issue a new certificate to the person
entitled thereto, cancel the old certificate and record the transaction upon its
books.

     The corporation may issue the whole or any part of its shares as partly
paid and subject to call for the remainder of the consideration to be paid
therefor.  Upon the face or back of each stock certificate issued to represent
any such partly paid shares, or upon the books and records of the corporation in
the case of uncertificated partly paid shares, the total amount of the
consideration to be paid therefor and the amount paid thereon shall be stated.
Upon the declaration of any dividend on fully paid shares, the corporation shall
declare a dividend upon partly paid shares of the same class, but only upon the
basis of the percentage of the consideration actually paid thereon.

8.5  SPECIAL DESIGNATION ON CERTIFICATES
     -----------------------------------

     If the corporation is authorized to issue more than one class of stock or
more than one series of any class, then the powers, the designations, the
preferences and the relative, participating, optional or other special rights of
each class of stock or series thereof and the qualifications, limitations or
restrictions of such preferences and/or rights shall be set forth in full or
summarized on the face or back of the certificate that the corporation shall
issue to represent such class or series of stock; provided, however, that,
except as otherwise provided in Section 202 of the General Corporation Law of
Delaware, in lieu of the foregoing requirements there may be set forth on the
face or back of the certificate that the corporation shall issue to represent
such class or series of stock a statement that the corporation will furnish
without charge to each stockholder who so requests the powers, the designations,
the preferences and the relative, participating, optional or other special
rights of each class of stock or series thereof and the qualifications,
limitations or restrictions of such preferences and/or rights.

8.6  LOST CERTIFICATES
     -----------------

     Except as provided in this Section 8.6, no new certificates for shares
shall be issued to replace a previously issued certificate unless the latter is
surrendered to the corporation and cancelled at the same time.  The board of
directors may, in case any share certificate or certificate for any other
security is lost, stolen or destroyed, authorize the issuance of replacement
certificates on such terms and conditions as the board may require; the board
may require indemnification of the corporation secured by a bond or other
adequate security sufficient to protect the corporation against any claim that
may be made against it, including any expense or liability, on account of the
alleged loss, theft or destruction of the certificate or the issuance of the
replacement certificate.

8.7  TRANSFER AGENTS AND REGISTRARS
     ------------------------------

     The board of directors may appoint one or more transfer agents or transfer
clerks, and one or more registrars, each of which shall be an incorporated bank
or trust company -- either domestic or foreign, who shall be appointed at such
times and places as the requirements of the corporation may necessitate and the
board of directors may designate.

8.8  CONSTRUCTION; DEFINITIONS
     -------------------------

                                      -17-
<PAGE>

     Unless the context requires otherwise, the general provisions, rules of
construction, and definitions in the General Corporation Law of Delaware shall
govern the construction of these bylaws.  Without limiting the generality of
this provision, the singular number includes the plural, the plural number
includes the singular, and the term "person" includes both a corporation and a
natural person.

                                  ARTICLE IX

                                  AMENDMENTS
                                  ----------

     The original or other bylaws of the corporation may be adopted, amended or
repealed by the stockholders entitled to vote or by the board of directors of
the corporation.  The fact that such power has been so conferred upon the
directors shall not divest the stockholders of the power, nor limit their power
to adopt, amend or repeal bylaws.

     Whenever an amendment or new bylaw is adopted, it shall be copied in the
book of bylaws with the original bylaws, in the appropriate place.  If any bylaw
is repealed, the fact of repeal with the date of the meeting at which the repeal
was enacted or the filing of the operative written consent(s) shall be stated in
said book.

                                      -18-
<PAGE>

                       CERTIFICATE OF ADOPTION OF BYLAWS

                                      OF

                        CENTILLIUM COMMUNICATIONS, INC.
                        -------------------------------

                           Adoption by Incorporator
                           ------------------------

     The undersigned person appointed in the Certificate of Incorporation to act
as the Incorporator of Centillium Communications, Inc. hereby adopts the
foregoing bylaws, comprising nineteen (19) pages, as the Bylaws of the
corporation.

     Executed this _____th day of November, 1999.


                                    /s/ Stephen Kim
                                    ____________________________________________
                                    Stephen Kim, Incorporator


             Certificate by Secretary of Adoption by Incorporator
             ----------------------------------------------------

     The undersigned hereby certifies that he is the duly elected, qualified,
and acting Secretary of Centillium Communications, Inc. and that the foregoing
Bylaws, comprising nineteen (19) pages, were adopted as the Bylaws of the
corporation on November __, 1999 by the person appointed in the Certificate of
Incorporation to act as the Incorporator of the corporation.

     IN WITNESS WHEREOF, the undersigned has hereunto set his hand and affixed
the corporate seal this _____th day of  November, 1999.


                                    /s/ Stephen Kim
                                    ____________________________________________
                                    Stephen Kim, Secretary

                                      -19-