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                                                                     EXHIBIT 4.2

                             SYNAPTICS INCORPORATED

              0.75% CONVERTIBLE SENIOR SUBORDINATED NOTES DUE 2024

                          REGISTRATION RIGHTS AGREEMENT

                                                                December 7, 2004


Bear, Stearns & Co. Inc.
Credit Suisse First Boston LLC
c/o Bear, Stearns & Co. Inc.
383 Madison Avenue
New York, NY 10179

Ladies and Gentlemen:

      Synaptics Incorporated, a Delaware corporation (the "Company"), proposes
to issue and sell to the initial purchasers named in the purchase agreement (the
"Initial Purchasers"), upon the terms set forth in such purchase agreement dated
December 1, 2004 (the "Purchase Agreement"), its 0.75% Convertible Senior
Subordinated Notes due 2024 (the "Securities"). As an inducement to the Initial
Purchasers to enter into the Purchase Agreement and in satisfaction of a
condition to the obligations of the Initial Purchasers thereunder, the Company
agrees with the Initial Purchasers for the benefit of Holders (as defined
herein) from time to time of the Registrable Securities (as defined herein) as
follows:

      1.    Definitions.

      (a)   Capitalized terms used herein without definition shall have the
meanings ascribed to them in the Purchase Agreement. As used in this Agreement,
the following defined terms shall have the following meanings:

      "Additional Interest" has the meaning assigned thereto in Section 7(a)
hereof.

      "Affiliate" of any specified person means any other person which, directly
or indirectly, is in control of, is controlled by, or is under common control
with such specified person. For purposes of this definition, control of a person
means the power, direct or indirect, to direct or cause the direction of the
management and policies of such person whether by contract or otherwise; and the
terms "controlling" and "controlled" have meanings correlative to the foregoing.

      "Business Day" means each Monday, Tuesday, Wednesday, Thursday and Friday
that is not a day on which banking institutions in the city of New York are
authorized or obligated by law or executive order to close.

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      "Commission" means the Securities and Exchange Commission, or any other
federal agency at the time administering the Exchange Act or the Securities Act,
whichever is the relevant statute for the particular purpose.

      "Common Stock" means the Company's common stock, par value $0.001 per
share.

      "DTC" means The Depository Trust Company.

      "Effectiveness Period" has the meaning assigned thereto in Section 2(b)(i)
hereof.

      "Effective Time" means the time at which the Commission declares any Shelf
Registration Statement effective or at which any Shelf Registration Statement
otherwise becomes effective.

      "Exchange Act" means the United States Securities Exchange Act of 1934, as
amended.

      "Holder" means any person that is the record owner of Registrable
Securities (and includes any person that has a beneficial interest in any
Registrable Security in book-entry form).

      "Indenture" means the Indenture, dated as of December 7, 2004, between the
Company and American Stock Transfer & Trust Company, pursuant to which the
Securities are to be issued, and as amended and supplemented from time to time
in accordance with its terms.

      "Issue Date" means the first date of original issuance of the Securities.

      "Majority of Holders" means Holders holding over 50% of the aggregate
principal amount of Registrable Securities outstanding.

      "Notice and Questionnaire" means a Selling Securityholder Notice and
Questionnaire substantially in the form of Appendix A hereto.

      "Notice Holder" has the meaning assigned thereto in Section 3(a)(iii)
hereof.

      The term "person" means an individual, partnership, corporation, trust or
unincorporated organization, or a government or agency or political subdivision
thereof.

      "Prospectus" means the prospectus included in any Shelf Registration
Statement, as amended or supplemented by any prospectus supplement with respect
to the terms of the offering of any portion of the Registrable Securities
covered by any Shelf Registration Statement and by all other amendments and
supplements to such prospectus, including all material incorporated by reference
in such prospectus and all documents filed after the date of such prospectus by
the Company under the Exchange Act and incorporated by reference therein.

      "Registrable Securities" means all or any portion of the Securities issued
from time to time under the Indenture and the shares of Common Stock issuable
upon conversion of such Securities until the earlier of: (x) the date on which
such security has been registered under the Securities Act and disposed of
pursuant to an effective registration statement, (y) the date that is two years
after the later of (1) the last date of original issuance of the Securities and
(2) the last date that the Company or any of its Affiliates was the owner of
such Securities (or any

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predecessor thereto), or such shorter period of time as permitted by Rule 144(k)
under the Securities Act or any successor provisions thereunder or (z) its sale
to the public pursuant to Rule 144 under the Securities Act.

      "Registration Default" has the meaning assigned thereto in Section 7(a)
hereof.

      "Securities Act" means the United States Securities Act of 1933, as
amended.

      "Shelf Registration" means a registration effected pursuant to Section 2
hereof.

      "Shelf Registration Statement" means a "shelf" registration statement
filed under the Securities Act providing for the registration of, and the sale
on a continuous or delayed basis by the Holders of, all of the Registrable
Securities pursuant to Rule 415 under the Securities Act and/or any similar rule
that may be adopted by the Commission, filed by the Company pursuant to the
provisions of Section 2 of this Agreement, including the Prospectus contained
therein, any amendments and supplements to such registration statement,
including post-effective amendments, and all exhibits and all material
incorporated by reference in such registration statement, and any additional
"shelf" registration statements filed under the Securities Act to permit the
registration and sale of Registrable Securities pursuant to Section 3(a)(ii)
hereof.

      "Suspension Period" has the meaning assigned thereto in Section 2(c)
hereof.

      "Trust Indenture Act" means the Trust Indenture Act of 1939, or any
successor thereto, and the rules, regulations and forms promulgated thereunder,
as the same shall be amended from time to time.

      The term "underwriter" means any underwriter, or any person deemed to be
an underwriter pursuant to the Securities Act and Exchange Act and the
respective rules and regulations thereunder, as in effect at any relevant time,
of Registrable Securities in connection with an offering thereof under a Shelf
Registration Statement.

      (b)   Wherever there is a reference in this Agreement to a percentage of
the "principal amount" of Registrable Securities or to a percentage of
Registrable Securities, each share of Common Stock issued upon conversion of the
Securities shall represent a principal amount or percentage of Registrable
Securities determined based on a quotient, (i) the numerator of which shall be
equal to the aggregate principal amount of Securities issued, less the aggregate
principal amount of Securities outstanding as of the date of determination, and
(ii) the denominator of which shall be equal to the aggregate number of shares
of Common Stock issued upon conversion of the Securities as of the date of
determination.

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      2.    Shelf Registration.

      (a)   The Company shall, no later than 90 calendar days following the
Issue Date, file with the Commission a Shelf Registration Statement relating to
the offer and sale of the Registrable Securities by the Holders from time to
time in accordance with the methods of distribution elected by such Holders,
subject to Section 3(n) hereof, and, thereafter, shall use its reasonable best
efforts to cause such initial Shelf Registration Statement to be declared
effective under the Securities Act no later than 180 calendar days following the
Issue Date; provided, however, that no Holder shall be entitled to be named as a
selling securityholder in any Shelf Registration Statement as of the date it is
declared effective or to use the Prospectus forming a part thereof for offers
and resales of Registrable Securities unless such Holder is a Notice Holder.

      (b)   The Company shall use its reasonable best efforts:

            (i)   to keep any Shelf Registration Statement effective,
      supplemented and amended as required by the provisions of Section 3(j)
      hereof, in order to permit the Prospectus forming a part thereof to be
      usable by Holders until the earlier of two years from the last date of
      original issuance of any Registrable Securities or such shorter period
      ending on the date that all Registrable Securities have ceased to be
      Registrable Securities (such period being referred to herein as the
      "Effectiveness Period"); and

            (ii)  after the Effective Time of the initial Shelf Registration
      Statement, as promptly as practicable but in any event within 5 Business
      Days or, if the Company is required to file with the Commission a new, or
      post-effective amendment to a, Shelf Registration Statement, 30 calendar
      days, of the receipt of a completed Notice and Questionnaire from any
      Holder of Registrable Securities that is not then a Notice Holder, to take
      any action reasonably necessary to enable such Holder to use the
      Prospectus forming a part thereof for resales of Registrable Securities,
      including, without limitation, any action necessary to identify such
      Holder as a selling securityholder in a Shelf Registration Statement;
      provided, however, that nothing in this subparagraph shall relieve such
      Holder of the obligation to return a completed and signed Notice and
      Questionnaire to the Company in accordance with Section 3(a)(ii) hereof.
      Notwithstanding the foregoing, the Company shall not be required to file
      more than one post-effective amendment to the Registration Statement in
      any calendar quarter.

The Company shall be deemed not to have used its reasonable best efforts to keep
any Shelf Registration Statement effective during the Effectiveness Period if
the Company voluntarily takes any action that would result in Holders of
Registrable Securities covered thereby not being able to offer and sell any of
such Registrable Securities during that period, unless such action is (A)
required by applicable law and the Company thereafter promptly complies with the
requirements of paragraph 3(j) below or (B) permitted pursuant to Section 2(c)
below.

      (c)   The Company may suspend the use of any Prospectus for a period not
to exceed 45 days in any 90-day period or an aggregate of 90 days in any
12-month period, during the period beginning on the last date of original
issuance and ending on or prior to the second anniversary of the last date of
original issuance of any Securities (each, a "Suspension Period") if the Board
of Directors of the Company shall have determined in good faith that because of
valid business reasons (not including avoidance of the Company's obligations
hereunder), including

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the acquisition or divestiture of assets, pending corporate developments and
similar events or because of filings with the Commission, it is in the best
interests of the Company to suspend such use, and prior to suspending such use
the Company provides the Holders with written notice of such suspension, which
notice need not specify the nature of the event giving rise to such suspension.

      3.    Registration Procedures. In connection with the Shelf Registration
Statements, the following provisions shall apply:

            (a)(i)  Not less than 30 calendar days prior to the intended
      Effective Time of the initial Shelf Registration Statement, the Company
      shall distribute the Notice and Questionnaire to the Holders of
      Registrable Securities. The Company shall take action to name each Holder
      that is a Notice Holder as of the date that is 5 Business Days prior to
      the effectiveness of the initial Shelf Registration Statement as a selling
      securityholder in the initial Shelf Registration Statement at the time of
      its effectiveness so that such Holder is permitted to deliver the
      Prospectus forming a part thereof as of such time to purchasers of such
      Holder's Registrable Securities in accordance with applicable law. The
      Company shall not be required to take any action to name any Holder as a
      selling securityholder in the initial Shelf Registration Statement or to
      enable any Holder to use the Prospectus forming a part thereof for resales
      of Registrable Securities until such Holder has returned a completed and
      signed Notice and Questionnaire to the Company.

              (ii)  From and after the Effective Time of the initial Shelf
      Registration Statement, the Company shall, upon the request of any Holder
      of Registrable Securities that is not then a Notice Holder, promptly send
      a Notice and Questionnaire to such Holder. From and after the Effective
      Time of the initial Shelf Registration Statement, the Company shall (A) as
      promptly as is practicable after the date a completed and signed Notice
      and Questionnaire is delivered to the Company, and in any event within 5
      Business Days or, if the Company is required to file with the Commission a
      new, or post-effective amendment to a, Shelf Registration, 30 calendar
      days, after such date, prepare and file with the Commission (x) a
      supplement to the Prospectus or, if required by applicable law, a
      post-effective amendment to the Shelf Registration Statement or an
      additional Shelf Registration Statement and (y) any other document
      required by applicable law, so that the Holder delivering such Notice and
      Questionnaire is named as a selling securityholder in a Shelf Registration
      Statement and is permitted to deliver the Prospectus to purchasers of such
      Holder's Registrable Securities in accordance with applicable law and (B)
      if the Company shall file a post-effective amendment to the Shelf
      Registration Statement, or an additional Shelf Registration Statement, use
      its reasonable best efforts to cause such post-effective amendment or such
      additional Shelf Registration Statement to become effective under the
      Securities Act as promptly as is practicable, but in any event by the date
      that is (i) 10 Business Days after the date such post-effective amendment
      is filed with the Commission or (ii) 45 calendar days after the date such
      additional Shelf Registration Statement is required to be filed; provided,
      however, that if a Notice and Questionnaire is delivered to the Company
      during a Suspension Period, the Company shall not be obligated to take the
      actions set forth in this clause (ii) until the termination of such
      Suspension Period. Notwithstanding the foregoing, the Company

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      shall not be required to file more than one post-effective amendment to
      the Registration Statement in any calendar quarter.

              (iii) The term "Notice Holder" shall mean any Holder of
      Registrable Securities that has returned a completed and signed Notice and
      Questionnaire to the Company in accordance with Section 3(a)(i) or
      3(a)(ii) hereof.

      (b)   Before filing any Shelf Registration Statement or Prospectus or any
amendments or supplements (other than supplements solely for the purpose of
naming one or more Notice Holders as selling securityholders) thereto with the
Commission, furnish to the Initial Purchasers copies of all such documents
proposed to be filed and use efforts to reflect in each such document when so
filed with the Commission such comments as the Initial Purchasers reasonably
shall reasonably propose within three (3) Business Days of the delivery of such
copies to the Initial Purchasers.

      (c)   The Company shall promptly take such action as may be necessary so
that (i) each of the Shelf Registration Statements and any amendment thereto and
the Prospectus forming a part thereof and any amendment or supplement thereto
(and each report or other document incorporated therein by reference in each
case) complies in all material respects with the Securities Act and the Exchange
Act and the respective rules and regulations thereunder, as in effect at any
relevant time, (ii) each of the Shelf Registration Statements and any amendment
thereto does not, when it becomes effective, contain an untrue statement of a
material fact or omit to state a material fact required to be stated therein or
necessary to make the statements therein not misleading, and (iii) each of the
Prospectus forming a part of any Shelf Registration Statement, and any amendment
or supplement to such Prospectus, in the form delivered to purchasers of the
Registrable Securities during the Effectiveness Period does not include an
untrue statement of a material fact or omit to state a material fact necessary
in order to make the statements therein, in the light of the circumstances under
which they were made, not misleading.

      (d)   The Company shall promptly advise each Notice Holder, and shall
confirm such advice in writing if so requested by any such Notice Holder:

            (i)   when the initial Shelf Registration Statement has been filed
      with the Commission and when the initial Shelf Registration Statement has
      become effective, in each case making a public announcement thereof by
      release made to Dow Jones & Company, Inc. or Bloomberg Business News or
      other similarly broad public medium that is customary for such releases;

            (ii)  when any Prospectus supplement, Shelf Registration Statement
      or post-effective amendment to a Shelf Registration has been filed with
      the Commission and, with respect to a Shelf Registration Statement or any
      post-effective amendment, when the same has been declared effective by the
      Commission;

            (iii) of any request by the Commission for amendments or supplements
      to any Shelf Registration Statement or the Prospectus included therein or
      for additional information, which notice shall be sent to legal counsel
      for the Notice Holders and need not be provided to each Notice Holder;

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            (iv)  of the issuance by the Commission of any stop order suspending
      the effectiveness of any Shelf Registration Statement or the initiation of
      any proceedings for such purpose;

            (v)   of the receipt by the Company of any notification with respect
      to the suspension of the qualification of the securities included in any
      Shelf Registration Statement for sale in any jurisdiction or the
      initiation of any proceeding for such purpose; and

            (vi)  of the happening of any event or the existence of any state of
      facts that requires the making of any changes in any Shelf Registration
      Statement or the Prospectus included therein so that, as of such date,
      such Shelf Registration Statement and Prospectus do not contain an untrue
      statement of a material fact and do not omit to state a material fact
      required to be stated therein or necessary to make the statements therein
      (in the case of the Prospectus, in the light of the circumstances under
      which they were made) not misleading (which advice shall be accompanied by
      an instruction to such Holders to suspend the use of the Prospectus until
      the requisite changes have been made, which notice need not specify the
      nature of the event giving rise to such suspension).

      (e)   The Company shall use its reasonable best efforts to prevent the
issuance, and if issued to obtain the withdrawal at the earliest possible time,
of any order suspending the effectiveness of any Shelf Registration Statement.

      (f)   As promptly as reasonably practicable furnish to each Notice Holder
and each Initial Purchaser, upon their request and without charge, at least one
(1) conformed copy of the Registration Statement and any amendment thereto,
including financial statements but excluding schedules, all documents
incorporated or deemed to be incorporated therein by reference and all exhibits
(unless requested in writing to the Company by such Notice Holder or such
Initial Purchaser, as the case may be).

      (g)   The Company shall, during the Effectiveness Period, deliver to each
Notice Holder, without charge, as many copies of each Prospectus in which the
Notice Holder is listed as a selling securityholder included in the applicable
Shelf Registration Statement and any amendment or supplement thereto as such
Notice Holder may reasonably request; and the Company consents (except during a
Suspension Period or during the continuance of any event described in Section
3(d) (iii)-(vi) above) to the use of the Prospectus and any amendment or
supplement thereto by each of the Notice Holders in connection with the offering
and sale of the Registrable Securities covered by the Prospectus and any
amendment or supplement thereto during the Effectiveness Period.

      (h)   Prior to any offering of Registrable Securities pursuant to a Shelf
Registration Statement, the Company shall (i) register or qualify or cooperate
with the Notice Holders and their respective counsel in connection with the
registration or qualification of such Registrable Securities for offer and sale
under the securities or "blue sky" laws of such jurisdictions within the United
States as any Notice Holder may reasonably request, (ii) keep such registrations
or qualifications in effect and comply with such laws so as to permit the
continuance of offers and sales in such jurisdictions for so long as may be
necessary to enable any Notice Holder or underwriter, if any, to complete its
distribution of Registrable Securities pursuant to such Shelf

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Registration Statement, and (iii) take any and all other actions necessary or
advisable to enable the disposition in such jurisdictions of such Registrable
Securities; provided, however, that in no event shall the Company be obligated
to (A) qualify as a foreign corporation or as a dealer in securities in any
jurisdiction where it would not otherwise be required to so qualify but for this
Section 3(h) or (B) subject itself to general or unlimited service of process or
to taxation in any such jurisdiction if they are not now so subject.

      (i)   Unless any Registrable Securities shall be in book-entry only form,
the Company shall cooperate with the Notice Holders to facilitate the timely
preparation and delivery of certificates representing Registrable Securities to
be sold pursuant to any Shelf Registration Statement, which certificates, if so
required by any securities market or exchange upon which any Registrable
Securities are quoted or listed, shall be penned, lithographed or engraved, or
produced by any combination of such methods, on steel engraved borders, and
which certificates shall be free of any restrictive legends and in such
permitted denominations and registered in such names as Notice Holders may
request in connection with the sale of Registrable Securities pursuant to such
Shelf Registration Statement.

      (j)   Upon the occurrence of any fact or event contemplated by paragraph
3(d)(vi) above, subject to Section 2(c) hereof, the Company shall promptly, but
in any event within seven Business Days following such occurrence, prepare, file
(and use its reasonable best efforts to have declared effective) a
post-effective amendment to any Shelf Registration Statement or an amendment or
supplement to the related Prospectus included therein or file any other document
with the Commission so that, as thereafter delivered to purchasers of the
Registrable Securities, the Prospectus will not include an untrue statement of a
material fact or omit to state any material fact necessary to make the
statements therein, in the light of the circumstances under which they were
made, not misleading. If the Company notifies the Notice Holders of the
occurrence of any fact or event contemplated by paragraph 3(d)(vi) above, the
Notice Holder shall suspend the use of the Prospectus until the requisite
changes to the Prospectus have been made.

      (k)   Not later than the Effective Time of a Shelf Registration Statement,
the Company shall provide a CUSIP number for the debt securities to be sold
pursuant to a Shelf Registration Statement.

      (l)   The Company shall comply with the Securities Act and the Exchange
Act and the respective rules and regulations thereunder, as in effect at any
relevant time, and make generally available to its securityholders earnings
statements (which need not be audited) satisfying the provisions of Section
11(a) of the Securities Act and Rule 158 thereunder (or any similar rule
promulgated under the Securities Act) no later than 45 days after the end of any
12-month period (or 90 days after the end of any 12-month period if such period
is a fiscal year), or such shorter period as required by the Securities Act and
the Exchange Act and the rules and regulations thereunder, as in effect at any
relevant time, commencing on the first day of the first fiscal quarter of the
Company commencing after (i) the effective date of a Shelf Registration
Statement, (ii) the effective date of each post-effective amendment to such
Shelf Registration Statement, or (iii) the date of each filing by the Company
with the Commission of an Annual Report on Form 10-K that is incorporated by
reference in such Shelf Registration Statement, which statements shall cover
said 12-month periods.

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      (m)   Not later than the Effective Time of the initial Shelf Registration
Statement, the Company shall cause the Indenture to be qualified under the Trust
Indenture Act; in connection with such qualification, the Company shall
cooperate with the Trustee under the Indenture and the Holders (as defined in
the Indenture) to effect such changes to the Indenture as may be required for
such Indenture to be so qualified in accordance with the terms of the Trust
Indenture Act; and the Company shall execute, and shall use its best efforts to
cause the Trustee to execute, all documents that may be required to effect such
changes and all other forms and documents required to be filed with the
Commission to enable such Indenture to be so qualified in a timely manner. In
the event that any such amendment or modification referred to in this Section
3(m) involves the appointment of a new trustee under the Indenture, the Company
shall appoint a new trustee thereunder pursuant to the applicable provisions of
the Indenture.

      (n)   The Company shall enter into such customary agreements and take all
such other actions as are reasonably necessary in connection therewith
(including those reasonably requested by the holders of a majority of the
Registrable Securities being sold) in order to expedite or facilitate
disposition of such Registrable Securities; provided, that the Company shall not
be required to take any action in connection with an underwritten offering
without its consent, with may be withheld in its sole and absolute discretion.

      (o)   The Company shall (A) make reasonably available for inspection by
one or more representatives of the selling Holders, designated in writing by a
Majority of Holders whose Registrable Securities are included in a Shelf
Registration Statement, any underwriter participating in any disposition
pursuant to any Shelf Registration Statement, and any attorney, accountant or
other agent retained by such Notice Holders or any such underwriter all relevant
financial and other records, pertinent corporate documents and properties of the
Company and its subsidiaries, and (B) cause the Company's officers, directors
and employees to supply all information reasonably requested by such Notice
Holders or any such underwriter, attorney, accountant or agent in connection
with such Shelf Registration Statement, in each case, as is customary for
similar due diligence examinations; provided, however, that such persons shall,
at the Company's request, first agree in writing with the Company that all
information shall be kept confidential by such persons and shall be used solely
for the purposes of exercising rights under this Agreement, unless such
disclosure is made in connection with a court proceeding or required by law, or
such records, information or documents become available to the public generally
or through a third party without an accompanying obligation of confidentiality;
and provided further that, if the foregoing inspection and information gathering
would otherwise disrupt the Company's conduct of its business, such inspection
and information gathering shall, to the greatest extent possible, be coordinated
on behalf of the Notice Holders and the other parties entitled thereto by one
counsel designated by and on behalf of the Notice Holders and other parties.

      (p)   The Company will use its reasonable best efforts to cause the Common
Stock issuable upon conversion of the Securities to be quoted or listed on the
Nasdaq National Market or other market or stock exchange on which the Common
Stock primarily trades on or prior to the Effective Time of each Shelf
Registration Statement hereunder.

      (q)   The Company will cooperate and assist in any filings or by taking
any other actions reasonably required to be made or taken with or by National
Association of Securities Dealers, Inc.

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      (r)   The Company shall use its reasonable best efforts to take all other
steps necessary to effect the registration, offering and sale of the Registrable
Securities covered by each Shelf Registration Statement contemplated hereby.

      4.    Registration Expenses. The Company shall bear all fees and expenses
incurred in connection with the performance by the Company of its obligations
under Sections 2 and 3 of this Agreement whether or not any of the Shelf
Registration Statements are declared effective. Such fees and expenses shall
include, without limitation, (i) all registration and filing fees (including,
without limitation, fees and expenses (x) with respect to filings required to be
made with the National Association of Securities Dealers, Inc. and (y) of
compliance with federal and state securities or Blue Sky laws to the extent such
filings or compliance are required pursuant to this Agreement (including,
without limitation, reasonable fees and disbursements of the counsel specified
in the next sentence in connection with Blue Sky qualifications of the
Registrable Securities under the laws of such jurisdictions as the Notice
Holders of a majority of the Registrable Securities being sold pursuant to a
Shelf Registration Statement may designate)), (ii) printing expenses (including,
without limitation, expenses of printing certificates for Registrable Securities
in a form eligible for deposit with The Depository Trust Company), (iii)
duplication expenses relating to copies of any Shelf Registration Statement or
Prospectus delivered to any Holders hereunder, (iv) fees and disbursements of
counsel for the Company in connection with the Shelf Registration Statement, and
(v) reasonable fees and disbursements of the Trustee and its counsel and of the
registrar and transfer agent for the Common Stock. In addition, the Company
shall pay the internal expenses of the Company (including, without limitation,
all salaries and expenses of officers and employees performing legal or
accounting duties), the expense of any annual audit, the fees and expenses
incurred in connection with the listing of the Registrable Securities on any
securities exchange on which similar securities of the Company are then listed
and the fees and expenses of any person, including special experts, retained by
the Company.

      5.    Indemnification and Contribution.

      (a)   Indemnification by the Company. The Company shall indemnify and hold
harmless each Notice Holder, each Initial Purchaser, and each person, if any,
who controls any such Notice Holder or Initial Purchaser within the meaning of
Section 15 of the Securities Act or Section 20 of the Exchange Act, from and
against any loss, claim, damage, liability or expense whatsoever incurred
(including but not limited to attorneys' fees and any and all expenses
whatsoever incurred in investigating, preparing or defending against any
litigation, commenced or threatened, or any claim whatsoever, and any and all
amounts paid in settlement of any claim or litigation), joint or several, to
which they or any of them may become subject under the Securities Act, the
Exchange Act or otherwise, insofar as any such loss, claim, damage, liability or
expense (or action in respect thereof) arises out of, or is based upon, any
untrue statement or alleged untrue statement of a material fact contained in the
Shelf Registration Statement or any amendment thereto or any related preliminary
prospectus or the Prospectus or any amendment thereto of supplement thereof, or
arises out of, or is based upon, the omission or alleged omission to state
therein any material fact required to be stated therein or necessary to make the
statements therein not misleading; provided, however, that the Company shall not
be liable to any such indemnified party in any such case to the extent that any
such loss, claim, damage, liability or expense arises out of, or is based upon,
any such untrue statement or alleged untrue statement or

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omission or alleged omission made therein in reliance upon and in conformity
with written information furnished to the Company by or on behalf of such
indemnified party specifically for use therein; and provided further, however,
that the Company shall not be liable to any such indemnified party in any such
case to the extent that such loss, claim, damage, liability or expense arises
from an offer or sale by a Notice Holder of Registrable Securities during a
Suspension Period, if such indemnified party is a Notice Holder that was
provided by the Company a notice of the commencement of such Suspension Period
prior to the making of such offer or sale. The foregoing indemnity agreement is
in addition to any liability that the Company may otherwise have to any
indemnified party.

      (b)   Indemnification by the Notice Holders. Each Notice Holder, severally
and not jointly, shall indemnify and hold harmless the Company, each director
and each officer of the Company, each Initial Purchaser, and each person, if
any, who controls the Company or any such Initial Purchaser within the meaning
of Section 15 of the Securities Act or Section 20 of the Exchange Act, from and
against any loss, claim, damage, liability or expense whatsoever incurred
(including but not limited to attorneys' fees and any and all expenses
whatsoever incurred in investigating, preparing or defending against any
litigation, commence or threatened, or any claim whatsoever, and any and all
amounts paid in settlement of any claim or litigation), joint or several, to
which they or any of them may become subject under the Securities Act, the
Exchange Act or otherwise, insofar as any such loss, claim, damage, liability or
expense (or action in respect thereof) arises out of, or is based upon, any
untrue statement or alleged untrue statement of a material fact contained in the
Shelf Registration Statement or any amendment thereto or any related preliminary
prospectus or the Prospectus or any amendment thereto of supplement thereof, or
arises out of, or is based upon, the omission or alleged omission to state
therein any material fact required to be stated therein or necessary to make the
statements therein not misleading, in each case to the extent, but only to the
extent, that such untrue statement or alleged untrue statement or omission or
alleged omission made therein was made in reliance upon and in conformity with
written information furnished to the Company by or on behalf of such Notice
Holder specifically for use therein. In no event shall the liability of any
selling Notice Holder hereunder be greater in amount than the dollar amount of
the proceeds received by such Holder upon the sale of the Registrable Securities
pursuant to the Shelf Registration Statement giving rise to such indemnification
obligation. The foregoing indemnity agreement is in addition to any liability
that any Notice Holder may otherwise have to the Company, any such Initial
Purchaser and any such controlling person.

      (c)   Notices of Claims, Etc. Promptly after receipt by an indemnified
party under this Section 5 of notice of any claim or the commencement of any
action, the indemnified party shall, if a claim in respect thereof is to be made
against the indemnifying party under this Section 5, notify the indemnifying
party in writing of the claim or the commencement of that action; provided,
however, that the failure to notify the indemnifying party shall not relieve it
from any liability that it may have under this Section 5. If any such claim or
action shall be brought against an indemnified party, and it shall notify the
indemnifying party thereof, the indemnifying party shall be entitled to
participate therein and, to the extent that it wishes, jointly with any other
similarly notified indemnifying party, to assume the defense thereof with
counsel satisfactory to the indemnified party. After notice from the
indemnifying party to the indemnified party of its election to assume the
defense of such claim or action, the indemnifying party shall not be liable to
the indemnified party under this Section 5 for any legal or other expenses
subsequently

                                       11
<PAGE>

incurred by the indemnified party in connection with the defense thereof other
than reasonable costs of investigation; provided, however, that the indemnified
party shall have the right to employ counsel to represent jointly the
indemnified party and its respective directors, employees, officers and
controlling persons who may be subject to liability arising out of any claim in
respect of which indemnity may be sought by the indemnified party against the
indemnifying party under this Section 5 if (1) employment of such counsel has
been authorized in writing by the indemnifying party, or (2) such indemnifying
party shall not have employed counsel to have charge of the defense of such
proceeding within 30 days of the receipt of notice thereof, or (3) such
indemnified party shall have reasonably concluded that the representation of
such indemnified party and those directors, employees, officers and controlling
persons by the same counsel representing the indemnifying party would be
inappropriate under applicable standards of professional conduct due to actual
or potential differing interests between them or where there may be one or more
defenses available to them that are different from, additional to or in conflict
with those available to the indemnifying party, and in any such event ((1), (2)
or (3)) the fees and expenses of such separate counsel shall be paid by the
indemnifying party as incurred. It is understood that the indemnifying party
shall not be liable for the fees and expenses of more than one separate firm (in
addition to local counsel in each jurisdiction) for all indemnified parties in
connection with any proceeding or related proceedings. No indemnifying party
shall, without the prior written consent of the indemnified parties, effect any
settlement or compromise of, or consent to the entry of judgment with respect
to, any pending or threatened claim, investigation, action or proceeding in
respect of which indemnity or contribution may be or could have been sought
hereunder (whether or not the indemnified party or parties are actual or
potential parties thereto) unless (x) such settlement, compromise or judgment
(i) includes an unconditional release of such indemnified party from all
liability arising out of such claim, action, suit or proceeding and (ii) does
not include a statement as to or an admission of fault, culpability or failure
to act by or on behalf of any indemnified party, and (y) the indemnifying party
confirms in writing its indemnification obligations hereunder with respect to
such settlement, compromise or judgment.

      (d)   Contribution. If the indemnification provided for in this Section 5
is unavailable or insufficient to hold harmless an indemnified party under
subsections (a) or (b) above, then each indemnifying party shall contribute to
the amount paid or payable by such indemnified party as a result of the losses,
claims, damages, expenses or liabilities (or actions in respect thereof)
referred to in subsection (a) or (b) above (i) in such proportion as is
appropriate to reflect the relative benefits received by the indemnifying party
or parties on the one hand and the indemnified party on the other from the
registration of the Registrable Securities pursuant to the Shelf Registration,
or (ii) if the allocation provided by the foregoing clause (i) is not permitted
by applicable law, in such proportion as is appropriate to reflect not only the
relative benefits referred to in clause (i) above but also the relative fault of
the indemnifying party or parties on the one hand and the indemnified party on
the other in connection with the statements or omissions that resulted in such
losses, claims, damages or liabilities (or actions in respect thereof) as well
as any other relevant equitable considerations. The relative fault of the
parties shall be determined by reference to, among other things, whether the
untrue or alleged untrue statement of a material fact or the omission or alleged
omission to state a material fact relates to information supplied by the Company
on the one hand or such Holder or such other indemnified party, as the case may
be, on the other, and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such statement or omission.
The amount paid

                                       12
<PAGE>

by an indemnified party as a result of the losses, claims, damages or
liabilities referred to in the first sentence of this subsection (d) shall be
deemed to include any legal or other expenses reasonably incurred by such
indemnified party in connection with investigating or defending any action or
claim which is the subject of this subsection (d). The Company and the Holders
agree that it would not be just and equitable if contribution pursuant to this
Section 5(d) were determined by pro rata allocation or by any other method of
allocation which does not take account of the equitable considerations referred
to herein. Notwithstanding any other provision of this Section 5(d), the Holders
of the Registrable Securities shall not be required to contribute any amount in
excess of the amount by which the gross proceeds received by such Holders from
the sale of the Registrable Securities pursuant to the Shelf Registration
Statement exceeds the amount of damages which such Holders have otherwise been
required to pay by reason of such untrue or alleged untrue statement or omission
or alleged omission. No person guilty of fraudulent misrepresentation (within
the meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation. For purposes of this paragraph (d), each person, if any, who
controls such indemnified party within the meaning of the Securities Act or the
Exchange Act shall have the same rights to contribution as such indemnified
party and each person, if any, who controls the Company within the meaning of
the Securities Act or the Exchange Act shall have the same rights to
contribution as the Company. The Holders' respective obligations to contribute
pursuant to this Section 5 are several in proportion to the respective amount of
Registrable Securities they have sold pursuant to a Registration Statement and
not joint. The remedies provided for in this Section 5 are not exclusive and
shall not limit any rights or remedies which may otherwise be available to any
indemnified party at law or in equity.

      (e)   The indemnity and contribution provisions contained in this Section
5 shall remain operative and in full force and effect regardless of (i) any
termination of this Agreement, (ii) any investigation made by or on behalf of
any Initial Purchaser, any Holder or any person controlling such Initial
Purchaser or Holder, or by or on behalf of the Company, its officers or
directors or any person controlling the Company, and (iii) any sale of
Registrable Securities pursuant to the Shelf Registration Statement.

      6.    Holder's Obligations. Each Holder agrees, by acquisition of the
Registrable Securities, that no Holder of Registrable Securities shall be
entitled to sell any of such Registrable Securities pursuant to a Shelf
Registration Statement or to receive a Prospectus relating thereto, unless such
Holder has furnished the Company with a Notice and Questionnaire as required
pursuant to Section 3(a)(ii) hereof (including the information required to be
included in such Notice and Questionnaire) and the information set forth in the
next sentence. Each Notice Holder agrees promptly to furnish to the Company all
information required to be disclosed in order to make the information previously
furnished to the Company by such Notice Holder not misleading and any other
information regarding such Notice Holder and the distribution of such
Registrable Securities as the Company may from time to time reasonably request.
Any sale of any Registrable Securities by any Notice Holder shall constitute a
representation and warranty by such Notice Holder that the information relating
to such Notice Holder and its plan of distribution is as set forth in the
Prospectus delivered by such Notice Holder in connection with such disposition,
that such Prospectus does not as of the time of such sale contain any untrue
statement of a material fact relating to or provided by such Notice Holder or
its plan of distribution and that such Prospectus does not as of the time of
such sale omit to

                                       13
<PAGE>

state any material fact relating to or provided by such Notice Holder or its
plan of distribution necessary in order to make the statements in such
Prospectus, in the light of the circumstances under which they were made, not
misleading.

      7.    Additional Interest.

      (a)   Notwithstanding any postponement of the effectiveness pursuant to
Section 2(a) hereof, if (i) on or prior to the 90th day following the Issue
Date, a Shelf Registration Statement has not been filed with the Commission,
(ii) on or prior to the 180th day following the Issue Date, such initial Shelf
Registration Statement is not declared effective by the Commission, (iii) after
the effectiveness date of any Shelf Registration Statement, (x) such Shelf
Registration Statement ceases to be effective or usable for the offer and sale
of Registrable Securities (other than due to a Suspension Period), and the
Company fails to file (and use its reasonable best efforts to have declared
effective), within seven Business Days, a post-effective amendment to such Shelf
Registration Statement or amendment or supplement to the Prospectus contained
therein or such other document with the Commission to make such Shelf
Registration Statement effective or such Prospectus usable, or (y) the
Suspension Periods exceed 45 days, whether or not consecutive, in any 90-day
period, or more than 90 days, whether or not consecutive, during any 12-month
period during the Effectiveness Period, or (iv) the Company shall have failed to
timely comply in all material respects with any of its obligations set forth in
Section 3(a)(ii) hereof (each, a "Registration Default"), the Company shall be
required to pay additional interest ("Additional Interest") pursuant to the
Securities, from and including the day following such Registration Default to
but excluding the day on which such Registration Default is cured, at a rate per
annum equal to an additional one-quarter of one percent (0.25%) of the principal
amount of the Securities to and including the 90th day following such
Registration Default, and one-half of one percent (0.5%) thereof from and after
the 91st day following such Registration Default.

      (b)   In the case of a Registration Default described in Sections
7(a)(i)-(iii) above, Additional Interest, if any, shall be payable only to
Notice Holders and, in respect of a Registration Default described in Section
7(a)(iv) above, Additional Interest, if any, shall be payable only to Notice
Holders to whom such Registration Default relates.

      (c)   Any amounts to be paid as Additional Interest pursuant to paragraph
(a) of this Section 7 shall be paid in cash semiannually in arrears, with the
first semiannual payment due on the first interest payment date following the
date on which such Additional Interest begins to accrue, to the Notice Holders
in whose name the Securities are registered at the close of business on May 15,
or November 15, whether or not a Business Day, immediately preceding the
relevant interest payment date.

      (d)   Except as provided in Section 8(a) hereof, and in Section 12.1(a) of
the Indenture, the Additional Interest as set forth in this Section 7 shall be
the exclusive monetary remedy available to the Holders of Registrable Securities
for such Registration Default. In no event shall the Company be required to pay
Additional Interest in excess of the applicable maximum amount of one-half of
one percent (0.5%) set forth above, regardless of whether one or multiple
Registration Defaults exist.

                                       14
<PAGE>

      8.    Miscellaneous.

      (a)   Specific Performance. The parties hereto acknowledge that there
would be no adequate remedy at law if the Company fails to perform any of its
obligations hereunder and that the Initial Purchasers and the Holders from time
to time may be irreparably harmed by any such failure, and accordingly agree
that the Initial Purchasers and such Holders, in addition to any other remedy to
which they may be entitled at law or in equity and without limiting the remedies
available to the Notice Holders under Section 7 hereof, shall be entitled to
compel specific performance of the obligations of the Company under this
Registration Rights Agreement in accordance with the terms and conditions of
this Registration Rights Agreement, in any court of the United States or any
State thereof having jurisdiction.

      (b)   Amendments and Waivers. This Agreement, including this Section 8(b),
may be amended, and waivers or consents to departures from the provisions hereof
may be given, only by a written instrument duly executed by the Company and a
Majority of Holders. Each Holder of Registrable Securities outstanding at the
time of any such amendment, waiver or consent or thereafter shall be bound by
any amendment, waiver or consent effected pursuant to this Section 8(b), whether
or not any notice, writing or marking indicating such amendment, waiver or
consent appears on the Registrable Securities or is delivered to such Holder.

      (c)   Notices. All notices and other communications provided for or
permitted hereunder shall be made in writing by hand delivery, by telecopier, by
courier guaranteeing overnight delivery or by first-class mail, return receipt
requested, and shall be deemed given (i) when made, if made by hand delivery,
(ii) upon confirmation, if made by telecopier, (iii) one (1) Business Day after
being deposited with such courier, if made by overnight courier or (iv) on the
date indicated on the notice of receipt, if made by first-class mail, to the
parties as follows:

            (w) if to a Holder of Registrable Securities, at the most current
      address given by such Holder to the Company in a Notice and Questionnaire
      or any amendment thereto;

            (x) if to the Company, to:

            Synaptics Incorporated
            2381 Bering Drive
            San Jose, California 95131
            Attention:  Kermit Nolan
            Telephone : (408) 434-0110
            Facsimile: (408) 432-3361

            With a copy to:

            Greenberg Traurig, LLP
            2375 E. Camelback Road, Suite 700
            Phoenix, Arizona 85016
            Attention: Robert S. Kant
            Facsimile:  (602) 445-8100

            and

                                       15
<PAGE>

            (y) if to the Initial Purchasers, to:

            Bear, Stearns & Co. Inc.
            383 Madison Avenue
            New York, NY  10179
            Attention: Stephen Parish
            Facsimile: (212) 272-3485

or to such other address as such person may have furnished to the other persons
identified in this Section 8(c) in writing in accordance herewith.

      (d)   Parties in Interest. The parties to this Agreement intend that all
Holders of Registrable Securities shall be entitled to receive the benefits of
this Agreement and that any Notice Holder shall be bound by the terms and
provisions of this Agreement by reason of such election with respect to the
Registrable Securities which are included in a Shelf Registration Statement. All
the terms and provisions of this Agreement shall be binding upon, shall inure to
the benefit of and shall be enforceable by the respective successors and assigns
of the parties hereto and any Holder from time to time of the Registrable
Securities to the aforesaid extent. In the event that any transferee of any
Holder of Registrable Securities shall acquire Registrable Securities, in any
manner, whether by gift, bequest, purchase, operation of law or otherwise, such
transferee shall, without any further writing or action of any kind, be entitled
to receive the benefits of and, if a Notice Holder, be conclusively deemed to
have agreed to be bound by and to perform all of the terms and provisions of
this Agreement to the aforesaid extent.

      (e)   Counterparts. This Agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

      (f)   Headings. The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

      (g)   Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of New York.

      (h)   Severability. In the event that any one or more of the provisions
contained herein, or the application thereof in any circumstances, is held
invalid, illegal or unenforceable in any respect for any reason, the validity,
legality and enforceability of any such provision in every other respect and of
the remaining provisions hereof shall not be in any way impaired or affected
thereby, it being intended that all of the rights and privileges of the parties
hereto shall be enforceable to the fullest extent permitted by law.

      (i)   Survival. The respective indemnities, agreements, representations,
warranties and other provisions set forth in this Agreement or made pursuant
hereto shall remain in full force and effect, regardless of any investigation
(or any statement as to the results thereof) made by or on behalf of any Notice
Holder, any director, officer or partner of such Holder, any agent or
underwriter, any director, officer or partner of such agent or underwriter, or
any controlling

                                       16
<PAGE>

person of any of the foregoing, and shall survive the transfer and registration
of the Registrable Securities of such Holder.

      9.    Submission to Jurisdiction; Appointment of Agent for Service

      The Company agrees that any suit, action or proceeding against the Company
arising out of or based upon this Agreement or the transactions contemplated
hereby may be instituted in any State or Federal court in the city of New York,
New York, and waives any objection which it may now or hereafter have to the
laying of venue of any such proceeding, and irrevocably submits to the
non-exclusive jurisdiction of such courts in any suit, action or proceeding. The
Company expressly accepts the non-exclusive jurisdiction of any such court in
respect of any such suit, action or proceeding. The Company agrees that a final
judgment in any such proceeding brought in any such court shall be conclusive
and binding thereupon and may be enforced in any other court in the jurisdiction
to which the Company is or may be subject by suit upon such judgment.

                            [Signature Page Follows]

                                       17
<PAGE>

            Please confirm that the foregoing correctly sets forth the agreement
between the Company and you.

                                              Very truly yours,

                                              Synaptics Incorporated

                                              By: /s/ Russell J. Knittel
                                                  ------------------------------
                                                  Name: Russell J. Knittel
                                                  Title: Senior Vice President
                                                         and Chief Financial
                                                         Officer

Accepted as of the date hereof:

      Bear, Stearns & Co. Inc.

      By: /s/ Paul S. Rosica
          -----------------------------
          Name: Paul S. Rosica
          Title: Senior Managing Director

      Credit Suisse First Boston LLC

      By: /s/ John Metz
          -----------------------------
          Name: John Metz
          Title: Managing Director

                [Signature Page to Registration Rights Agreement]

<PAGE>

                                                                      APPENDIX A

                             SYNAPTICS INCORPORATED
             FORM OF SELLING SECURITYHOLDER NOTICE AND QUESTIONNAIRE
              0.75% CONVERTIBLE SENIOR SUBORDINATED NOTES DUE 2024

      The undersigned beneficial owner of 0.75% Convertible Senior Subordinated
Notes due 2024 (the "Notes") of Synaptics Incorporated (the "Company" or
"Registrant") or Common Stock, par value $0.001 per share (the "Common Stock"
and, together with the Notes, the "Registrable Securities"), of the Company
understands that the Registrant has filed or intends to file with the U.S.
Securities and Exchange Commission (the "Commission") a registration statement
on Form S-3 (the "Shelf Registration Statement") for the registration and resale
under Rule 415 of the Securities Act of 1933, as amended (the "Securities Act"),
of the Registrable Securities, in accordance with the terms of the Registration
Rights Agreement, dated as of December 7, 2004 (the "Registration Rights
Agreement"), between the Company and the initial purchasers named therein. A
copy of the Registration Rights Agreement is available from the Company upon
request at the address set forth below. All capitalized terms not otherwise
defined herein shall have the meanings ascribed thereto in the Registration
Rights Agreement.

      Each beneficial owner of Registrable Securities is entitled to the
benefits of the Registration Rights Agreement. In order to sell or otherwise
dispose of any Registrable Securities pursuant to the Shelf Registration
Statement, a beneficial owner of Registrable Securities generally will be
required to be named as a selling securityholder in the related prospectus,
deliver a prospectus to purchasers of Registrable Securities and be bound by the
provisions of the Registration Rights Agreement applicable to such beneficial
owner (including certain indemnification provisions described below). Beneficial
owners that do not complete this Notice and Questionnaire and deliver it to the
Company as provided below will not be named as selling securityholders in the
prospectus and therefore will not be permitted to sell any Registrable
Securities pursuant to the Shelf Registration Statement. Beneficial owners are
encouraged to complete and deliver this Notice and Questionnaire prior to the
effectiveness of the Shelf Registration Statement so that such beneficial owners
may be named as selling securityholders in the related prospectus. Upon receipt
of a completed Notice and Questionnaire from a beneficial owner following the
effectiveness of the Shelf Registration Statement, the Company will, as promptly
as practicable but in any event within (i) 5 business days of such receipt, file
such supplements to the related prospectus, or (ii) 30 calendar days of such
receipt, file a post-effective amendment to the Shelf Registration Statement or
an additional Shelf Registration Statement with the Commission if required to do
so, in each case as are necessary to permit such holder to deliver such
prospectus to purchasers of Registrable Securities. The Company will not be
required, however, to file more than one post-effective amendment to a Shelf
Registration Statement for such purpose in any calendar quarter.

      Certain legal consequences arise from being named as a selling
securityholder in the Shelf Registration Statement and the related prospectus.
Accordingly, holders and beneficial owners of Registrable Securities are advised
to consult their own securities law counsel regarding the consequences of being
named or not being named as a selling securityholder in the Shelf Registration
Statement and the related prospectus.

<PAGE>

                                                                      APPENDIX A

                                     NOTICE

      The undersigned beneficial owner (the "Selling Securityholder") of
Registrable Securities hereby gives notice to the Company of its intention to
sell or otherwise dispose of Registrable Securities beneficially owned by it and
listed below in Item 3 (unless otherwise specified under such Item 3) pursuant
to the Shelf Registration Statement. The undersigned, by signing and returning
this Notice and Questionnaire, understands that it will be bound by the terms
and conditions of this Notice and Questionnaire and the Registration Rights
Agreement.

      Pursuant to the Registration Rights Agreement, the undersigned has agreed
to indemnify and hold harmless the Company's directors and officers and each
person, if any, who controls the Company within the meaning of either Section 15
of the Securities Act or Section 20 of the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), from and against certain losses arising in
connection with statements concerning the undersigned made in the Company's
Shelf Registration Statement or the related prospectus in reliance upon the
information provided in this Notice and Questionnaire.

      If the Selling Securityholder transfers all or any portion of the
Registrable Securities listed in Item 3 below after the date on which such
information is provided to the Company, the Selling Securityholder agrees to
notify the transferee(s) at the time of the transfer of its rights and
obligations under this Notice and Questionnaire and the Registration Rights
Agreement.

<PAGE>

                                                                      APPENDIX A

                                  QUESTIONNAIRE

      Please respond to every item, even if your response is "none." If you need
more space for any response, please attach additional sheets of paper. Please be
sure to indicate your name and the number of the item being responded to on each
such additional sheet of paper, and to sign each such additional sheet of paper
before attaching it to this Questionnaire. Please note that you may be asked to
answer additional questions depending on your responses to the following
questions.

      If you have any questions about the contents of this Questionnaire or as
to who should complete this Questionnaire, please contact Mr. Nolan at Synaptics
Incorporated at telephone number: (408) 434-0110.

            COMPLETED QUESTIONNAIRES SHOULD BE RETURNED TO SYNAPTICS
                            INCORPORATED AS FOLLOWS:

            1 COPY BY FACSIMILE TO KERMIT NOLAN, DIRECTOR OF FINANCE,
                               FAX: (408) 432-3361

                      WITH THE ORIGINAL COPY TO FOLLOW TO:
                             SYNAPTICS INCORPORATED
                                2381 BERING DRIVE
                           SAN JOSE, CALIFORNIA 95131
                  ATTENTION: KERMIT NOLAN, DIRECTOR OF FINANCE
                               TEL: (408) 434-0110

      The undersigned hereby provides the following information to the Company
and represents and warrants that such information is accurate and complete:

1.    YOUR IDENTITY AND BACKGROUND AS THE BENEFICIAL OWNER OF THE REGISTRABLE
      SECURITIES

      (a)   Your full legal name:

      (b)   Your business address (including street address) (or residence if no
            business address), telephone number, and facsimile number:

            Address: ___________________________________________________________
                     ___________________________________________________________

            Telephone No.: _____________________________________________________

            Fax No.: ___________________________________________________________

<PAGE>

                                                                      APPENDIX A

      (c)   Are you a broker-dealer registered pursuant to Section 15 of the
            Exchange Act?

            [ ]   Yes.

            [ ]   No.

      (d)   If your response to Item 1(c) above is no, are you an "affiliate" of
            a broker-dealer registered pursuant to Section 15 of the Exchange
            Act?

            [ ]   Yes.

            [ ]   No.

            For the purposes of this Item 1(d), an "affiliate" of a registered
            broker-dealer shall include any company that directly, or indirectly
            through one or more intermediaries, controls, or is controlled by,
            or is under common control with such broker-dealer, and does not
            include any individuals employed by such broker-dealer or its
            affiliates.

      (e)   Full legal name of person through which you hold the Registrable
            Securities (i.e., name of your broker or the DTC participant, if
            applicable, through which your Registrable Securities are held):

            Name of broker: ____________________________________________________

            DTC No.: ___________________________________________________________

            Contact person: ____________________________________________________

            Telephone No.: _____________________________________________________

2.    YOUR RELATIONSHIP WITH SYNAPTICS INCORPORATED

      (a)   Have you or any of your affiliates, officers, directors, or
            principal equity holders (owners of 5% or more of the equity
            securities of the undersigned) held any position or office, or have
            you had any other material relationship with, Synaptics Incorporated
            (or its predecessors or affiliates) within the past three years?

            [ ]   Yes.

            [ ]   No.

      (b)   If your response to Item 2(a) above is yes, please state the nature
            and duration of your relationship with Synaptics Incorporated:

<PAGE>

                                                                      APPENDIX A

3.    YOUR INTEREST IN THE REGISTRABLE SECURITIES

      (a)   State the type of Registrable Securities (Notes or Common Stock) and
            the principal amount or number of such Registrable Securities
            beneficially owned by you. Check any of the following that applies
            to you.

            [ ]   I own Notes:

            Principal amount and CUSIP No. of the Notes beneficially owned:

            Principal Amount: __________________________________________________

            CUSIP No(s): _______________________________________________________

            [ ]   I own shares of Common Stock that were issued upon conversion
                  of the Notes:

            Number of shares and CUSIP No. of the Common Stock beneficially
            owned:

            Number of shares: __________________________________________________

            CUSIP No(s): _______________________________________________________

      (b)   Other than as set forth in your response to Item 3(a) above, do you
            beneficially own any other securities of Synaptics Incorporated
            (including any Notes previously registered under the Securities
            Act)?

            [ ]   Yes.

            [ ]   No.

      (c)   If your answer to Item 3(b) above is yes, state the type, the
            aggregate amount, and CUSIP No. of such other securities of
            Synaptics Incorporated beneficially owned by you:

            Type: ______________________________________________________________

            Aggregate amount: __________________________________________________

            CUSIP No.: _________________________________________________________

      (d)   Did you acquire the securities listed in Item 3(a) above in the
            ordinary course of business?

            [ ]   Yes.

            [ ]   No.

<PAGE>

                                                                      APPENDIX A

      (e)   At the time of your purchase of the securities listed in Item 3(a)
            above, did you have any agreements or understandings, directly or
            indirectly, with any person to distribute the securities?

            [ ]   Yes.

            [ ]   No.

      (f)   If your response to Item 3(e) above is yes, please describe such
            agreements or understandings:

            ____________________________________________________________________
            ____________________________________________________________________

4.    NATURE OF YOUR BENEFICIAL OWNERSHIP

      (a)   If the name of the beneficial owner of the Registrable Securities
            set forth in your response to Item 1(a) above is that of a limited
            partnership, state the names of the general partners of such limited
            partnership:

            ____________________________________________________________________
            ____________________________________________________________________
            ____________________________________________________________________

      (b)   With respect to each general partner listed in Item 4(a) above who
            is not a natural person, and is not publicly held, name each
            shareholder (or holder of partnership interests, if applicable) of
            such general partner. If any of these named shareholders is not a
            natural person or publicly held entity, please provide the same
            information. This process should be repeated until you reach natural
            persons or a publicly held entity.

            ____________________________________________________________________
            ____________________________________________________________________
            ____________________________________________________________________

      (c)   Name your controlling shareholder(s) (the "Controlling Entity"). If
            the Controlling Entity is not a natural person and is not a publicly
            held entity, name each shareholder of such Controlling Entity. If
            any of these named shareholders are not natural persons or publicly
            held entities, please provide the same information. This process
            should be repeated until you reach natural persons or a publicly
            held entity.

<PAGE>

                                                                      APPENDIX A

            (A)(i) Full legal name of Controlling Entity(ies) or natural
                   person(s) that have sole or shared voting or dispositive
                   power over the Registrable Securities:

                   _____________________________________________________________

            (ii)   Name of shareholders:

                   _____________________________________________________________
                   _____________________________________________________________

            (B)(i) Full legal name of Controlling Entity(ies):

                   _____________________________________________________________
                   _____________________________________________________________

            (ii)   Name of shareholders:

                   _____________________________________________________________
                   _____________________________________________________________

IF YOU NEED MORE SPACE FOR THIS RESPONSE, PLEASE ATTACH ADDITIONAL SHEETS OF
PAPER. PLEASE BE SURE TO INDICATE YOUR NAME AND THE NUMBER OF THE ITEM BEING
RESPONDED TO ON EACH SUCH ADDITIONAL SHEET OF PAPER, AND TO SIGN EACH SUCH
ADDITIONAL SHEET OF PAPER BEFORE ATTACHING IT TO THIS QUESTIONNAIRE. PLEASE NOTE
THAT YOU MAY BE ASKED TO ANSWER ADDITIONAL QUESTIONS DEPENDING ON YOUR RESPONSES
TO THESE QUESTIONS.

5.    PLAN OF DISTRIBUTION

Except as set forth below, the undersigned (including its donees or pledgees)
intends to distribute the Registrable Securities listed above in Item 3 pursuant
to the Shelf Registration Statement only as follows (if at all): Such
Registrable Securities may be sold from time to time directly by the undersigned
or, alternatively, through underwriters, broker-dealers, or agents. If the
Registrable Securities are sold through underwriters, broker-dealers, or agents,
the Selling Securityholder will be responsible for underwriting discounts or
commissions or agents' commissions. Such Registrable Securities may be sold in
one or more transactions at fixed prices, at prevailing market prices at the
time of sale, at varying prices determined at the time of sale, or at negotiated
prices. Such sales may be effected in transactions (which may involve block
transactions) (i) on any national securities exchange or quotation service on
which the Registrable Securities may be listed or quoted at the time of sale,
(ii) in the over-the-counter market, (iii) in transactions otherwise than on
such exchanges or services or in the over-the-counter market, or (iv) through
the writing of options. In connection with sales of the Registrable Securities
or otherwise, the undersigned may enter into hedging transactions with
broker-dealers, which may in turn engage in short sales of the Registrable
Securities in the course of hedging positions they assume. The undersigned may
also sell Registrable Securities

<PAGE>

                                                                      APPENDIX A

short and deliver Registrable Securities to close out short positions, or loan
or pledge Registrable Securities to broker-dealers that in turn may sell such
securities.

State any exceptions here:

________________________________________________________________________________
________________________________________________________________________________

Note: In no event will such method(s) of distribution take the form of an
      underwritten offering of the Registrable Securities without the prior
      written agreement of the Company.

      The undersigned acknowledges its obligation to comply with the provisions
of the Exchange Act and the rules thereunder relating to stock manipulation,
particularly Regulation M thereunder (or any successor rules or regulations), in
connection with any offering of Registrable Securities pursuant to the
Registration Rights Agreement. The undersigned agrees that neither it nor any
person acting on its behalf will engage in any transaction in violation of such
provisions.

      The undersigned beneficial owner and selling securityholder hereby
acknowledges its obligations under the Registration Rights Agreement to
indemnify and hold harmless certain persons as set forth therein. Pursuant to
the Registration Rights Agreement, the Company has agreed under certain
circumstances to indemnify the undersigned beneficial owner and selling
securityholder against certain liabilities.

      In accordance with the undersigned's obligation under the Registration
Rights Agreement to provide such information as may be required by law for
inclusion in the Shelf Registration Statement, the undersigned agrees to
promptly notify the Company of any inaccuracies or changes in the information
provided herein that may occur subsequent to the date hereof at any time while
the Shelf Registration Statement remains effective.

      All notices to the beneficial owner hereunder and pursuant to the
Registration Rights Agreement shall be made in writing to the undersigned at the
address set forth in Item 1(b) of this Notice and Questionnaire.

      By signing below, the undersigned acknowledges that it is the beneficial
owner of the Registrable Securities set forth herein, represents that the
information provided herein is accurate, and consents to the disclosure of the
information contained in this Notice and Questionnaire and the inclusion of such
information in the Shelf Registration Statement and the related prospectus. The
undersigned understands that such information will be relied upon by the Company
in connection with the preparation or amendment of the Shelf Registration
Statement and the related prospectus.

      Once this Notice and Questionnaire is executed by the undersigned
beneficial owner and received by the Company, the terms of this Notice and
Questionnaire, and the representations and warranties contained herein, shall be
binding on, shall inure to the benefit of, and shall be enforceable by the
respective successors, heirs, personal representatives, and assigns of the

<PAGE>

                                                                      APPENDIX A

Company and the undersigned beneficial owner. This Agreement shall be governed
in all respects by the laws of the state of New York.

<PAGE>

                                                                      APPENDIX A

      IN WITNESS WHEREOF the undersigned, by authority duly given, has caused
this Notice and Questionnaire to be executed and delivered either in person or
by its duly authorized agent.

                                        NAME OF BENEFICIAL OWNER:

                                        ________________________________________

                                                   (Please Print)

                                       Signature: ______________________________

                                       Date: ___________________________________