SIGMATEL, INC. AMENDED AND RESTATED EXECUTIVE CHANGE IN CONTROL SEVERANCE PLAN

Exhibit 99.2

SIGMATEL, INC.

AMENDED AND RESTATED

EXECUTIVE CHANGE IN CONTROL SEVERANCE PLAN

1.1 Establishment. The SigmaTel, Inc. Executive Change in Control Severance Plan, as originally established by the Compensation Committee of the Board of Directors of SigmaTel, Inc., effective August 31, 2006 (the “Effective Date”), is hereby amended and restated in its entirety as set forth below (as amended and restated, the “ Plan ”).

1.2 Purpose. The Company draws upon the knowledge, experience and advice of its Executive Officers in order to manage its business for the benefit of the Company’s stockholders. Due to the widespread awareness of the possibility of mergers, acquisitions and other strategic alliances in the Company’s industry, the topic of compensation and other employee benefits in the event of a Change in Control is an issue in competitive recruitment and retention efforts. The Committee recognizes that the possibility or pending occurrence of a Change in Control could lead to uncertainty regarding the consequences of such an event and could adversely affect the Company’s ability to attract, retain and motivate its Executive Officers. The Committee has therefore determined that it is in the best interests of the Company and its stockholders to provide for the continued dedication of its Executive Officers notwithstanding the possibility or occurrence of a Change in Control by establishing this Plan to provide designated Executive Officers with enhanced financial security in the event of a Change in Control. The purpose of this Plan is to provide its Participants with specified compensation and benefits in the event of termination of employment under circumstances specified herein upon or following a Change in Control.

2.1 Definitions. Whenever used in this Plan, the following terms shall have the meanings set forth below:

(a) “ Base Salary Rate ” means the greater of (1) the Participant’s monthly base salary rate in effect immediately prior to the Participant’s Termination Upon a Change in Control or (2) the Participant’s monthly base salary rate in effect immediately prior to the applicable Change in Control. For this purpose, base salary does not include any bonuses, commissions, fringe benefits, car allowances, other irregular payments or any other compensation except base salary.

(b) “ Benefit Period ” means a period of twelve (12) months.

(c) “ Board ” means the Board of Directors of the Company.

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(d) “ Cause ” means the occurrence of any of the following: (1) the Participant’s theft, dishonesty, misconduct, breach of fiduciary duty for personal profit, or falsification of any documents or records of the Company Group; (2) the Participant’s material failure to abide by the code of conduct or other policies (including, without limitation, policies relating to confidentiality and reasonable workplace conduct) of any member of the Company Group; (3) misconduct by the Participant within the scope of Section 304 of the Sarbanes-Oxley Act of 2002 as a result of which of the Company is required to prepare an accounting restatement; (4) the Participant’s unauthorized use, misappropriation, destruction or diversion of any tangible or intangible asset or corporate opportunity of a member of the Company Group (including, without limitation, the Participant’s improper use or disclosure of the confidential or proprietary information of a member of the Company Group); (5) any intentional act by the Participant which has a material detrimental effect on reputation or business of a member of the Company Group; (6) the Participant’s repeated failure or inability to perform any reasonable assigned duties after written notice from a member of the Company Group of, and a reasonable opportunity to cure such failure or inability; (7) any material breach by the Participant of any employment, non-disclosure, non-competition, non-solicitation or other similar agreement between the Participant and a member of the Company Group, which breach is not cured pursuant to the terms of such agreement; or (8) the Participant’s conviction (including any plea of guilty or nolo contendere) of any criminal act involving fraud, dishonesty, misappropriation or moral turpitude, or which impairs the Participant’s ability to perform his or her duties with a member of the Company Group.

(e) “ Change in Control ” means the occurrence of any of the following:

(1) any “person” (as such term is used in Sections 13(d) and 14(d) of the Securities Exchange Act of 1934, as amended (the “ Exchange Act ” )), other than a trustee or other fiduciary holding securities of the Company under an employee benefit plan of the Company, becomes the “beneficial owner” (as defined in Rule 13d-3 promulgated under the Exchange Act), directly or indirectly, of securities of the Company representing more than fifty percent (50%) of the total combined voting power of the Company’s then-outstanding securities entitled to vote generally in the election of directors;

(2) the Company is party to a merger or consolidation which results in the holders of the voting securities of the Company outstanding immediately prior thereto failing to retain immediately after such merger or consolidation direct or indirect beneficial ownership of more than fifty percent (50%) of the total combined voting power of the securities entitled to vote generally in the election of directors of the Company or the surviving entity outstanding immediately after such merger or consolidation;

(3) the sale or disposition of all or substantially all of the Company’s assets or consummation of any transaction having similar effect (other than a sale or disposition to one or more subsidiaries of the Company); or

(4) a change in the composition of the Board within any twelve (12) month period as a result of which fewer than a majority of the directors are Incumbent Directors;

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provided; however , that to the extent that any amount constituting nonqualified deferred compensation subject to Section 409A of the Code would become payable under this Plan by reason of a Change in Control, such amount shall become payable only if the event constituting a Change in Control would also constitute a change in ownership or effective control of the Company, or a change in the ownership of a substantial portion of the assets of the Company, within the meaning of Section 409A of the Code; provided, further, that to the extent the accelerated vesting of an Equity Award is limited by the terms of a governing plan document, the definition of “Change in Control” in such governing document shall control with respect to such Equity Award.

(f) “ Change in Control Period ” means a period commencing upon the date of the consummation of a Change in Control and ending on the date occurring twenty-four (24) months thereafter.

(g) “ Code ” means the Internal Revenue Code of 1986, as amended, or any successor thereto and any applicable regulations (including proposed or temporary regulations) and other Internal Revenue Service guidance promulgated thereunder.

(h) “ Committee ” means the Compensation Committee of the Board.

(i) “ Company ” means SigmaTel, Inc., a Delaware corporation, and, following a Change in Control, a Successor that agrees to assume all of the terms and provisions of this Plan or a Successor which otherwise becomes bound by operation of law to this Plan.

(j) “ Company Group ” means the group consisting of the Company and each present or future parent and subsidiary corporation or other business entity thereof.

(k) “ Disability ” means a Participant’s permanent and total disability within the meaning of Section 22(e)(3) of the Code.

(l) “ Executive Officer ” means an individual who, immediately prior to the consummation of a Change in Control, serves as an executive officer of the Company Group appointed by the Board.

(m) “ Equity Award ” means any Option, Stock Appreciation Rights, Restricted Stock, Restricted Stock Units or other stock-based compensation award.

(n) “ Good Reason ” means the occurrence during a Change in Control Period of any of the following conditions without the Participant’s informed written consent, which condition(s) remain(s) in effect twenty (20) days after written notice to the Company from the Participant of such condition(s):

(1) a material, adverse change in the Participant’s position, duties, substantive functional responsibilities or reporting relationships, causing the Participant’s position to be of materially lesser rank or responsibility within the Company or an equivalent business unit of its parent as measured by the position occupied by the Participant immediately prior to the Change in Control, provided, however, the elimination of the Participant’s duties associated with operating and maintaining the Company Group as a publically traded company (in the event that the Company Group ceases to be a publically traded company after a Change of Control), shall not, taken alone, constitute a material adverse change; or

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(2) a decrease in the Participant’s base salary rate or a decrease in the Participant’s target bonus amount (subject to applicable performance requirements with respect to the actual amount of bonus compensation earned by the Participant); or

(3) any failure by the Company Group to (i) continue to provide the Participant with the opportunity to participate, on terms substantially similar in the aggregate to those in effect for the benefit of any employee group which customarily includes a person holding the employment position or a comparable position with the Company Group then held by the Participant, in any benefit or compensation plans or programs that are substantially similar in the aggregate to the plans and programs, including, but not limited to, the Company Group’s life, disability, health, dental, medical, savings, profit sharing, stock purchase and retirement plans, if any, in which the Participant was participating immediately prior to the Change in Control, or (ii) provide the Participant with all other fringe benefits (or their equivalent) from time to time in effect for the benefit of any employee group which customarily includes a person holding the employment position or a comparable position with the Company Group then held by the Participant; or

(4) the relocation of the Participant’s work place for the Company Group to a location that increases the regular commute distance between the Participant’s residence and work place by more than thirty (30) miles (one-way), or, following the consummation of a Change in Control, the imposition of business travel requirements substantially more demanding of the Participant than such travel requirements existing immediately prior to the Change in Control; or

(5) any material breach of this Plan by the Company Group with respect to the Participant.

The existence of Good Reason shall not be affected by the Participant’s temporary incapacity due to physical or mental illness not constituting a Disability. The Participant’s continued employment for a period not exceeding sixty (60) days following the occurrence of any condition constituting Good Reason shall not constitute consent to, or a waiver of rights with respect to, such condition. For the purposes of any determination regarding the existence of Good Reason, any claim by the Participant that Good Reason exists shall be presumed to be correct unless the Company establishes to the Board that Good Reason does not exist, and the Board, acting in good faith, affirms such determination by a vote of not less than two-thirds of its entire membership (excluding the Participant if the Participant is a member of the Board).

(o) “ Incumbent Director ” means a director who either (1) is a member of the Board as of the Effective Date, or (2) is elected, or nominated for election, to the Board with the affirmative votes of at least a majority of the Incumbent Directors at the time of such election or nomination, but (3) was not elected or nominated in connection with an actual or threatened proxy contest relating to the election of directors of the Company.

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(p) “ Option ” means any option to purchase shares of the capital stock of the Company or of any other member of the Company Group granted to a Participant by the Company or any other Company Group member, whether granted before or after a Change in Control.

(q) “ Participant ” means each Executive Officer designated by the Committee to participate in the Plan, provided such individual has executed a Participation Agreement.

(r) “ Participation Agreement ” means an Agreement to Participate in the SigmaTel, Inc. Executive Change in Control Severance Plan in the form attached hereto as Exhibit A or in such other form as the Committee may approve from time to time; provided, however, that, after a Participation Agreement has been entered into between a Participant and the Company, it may be modified only by a supplemental written agreement executed by both the Participant and the Company. The terms of such forms of Participation Agreement need not be identical with respect to each Participant. For example, a Participation Agreement may limit the duration of a Participant’s participation in the Plan or may modify the definition of “Change in Control” with respect to a Participant.

(s) “ Prior Year Bonus ” means the greater of the maximum aggregate amount of all bonuses for which the Participant was eligible (whether or not actually earned or paid) under the terms of the programs, plans or agreements providing for such bonuses with respect to the full fiscal year of the Company in effect immediately prior to (1) the Change in Control or (2) the Termination Upon a Change in Control, in either case irrespective of amounts already earned or paid with respect to such fiscal year.

(t) “ Release ” means a general release of all known and unknown claims against the Company and its affiliates and their stockholders, directors, officers, employees, agents, successors and assigns substantially in the form attached hereto as Exhibit B (“General Release of Claims [Age 40 and over]” or Exhibit C (“General Release of Claims [Under age 40]”), whichever is applicable to the Participant, with any modifications thereto determined by legal counsel to the Company to be necessary or advisable to comply with applicable law or to accomplish the intent of Section 7 (Exclusive Remedy) hereof.

(u) “ Restricted Stock ” means any compensatory award of shares of the capital stock of the Company or of any other member of the Company Group granted to a Participant by the Company or any other Company Group member or acquired upon the exercise of an Option, whether such shares are granted or acquired before or after a Change in Control, including any shares issued in exchange for any such shares by a Successor or any other member of the Company Group.

(v) “ Restricted Stock Units ” mean any compensatory award of rights to receive shares of the capital stock or cash in an amount measured by the value of shares of the capital stock of the Company or of any other member of the Company Group at one or more specified future times or upon the satisfaction of one or more specified conditions granted to a Participant by the Company or any other Company Group member, whether such awards are granted before or after a Change in Control, including any such awards granted in exchange for such awards by a Successor or any other member of the Company Group.

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(w) “ Separation from Service ” means a separation from service as defined in Section 409A of the Code.

(x) “ Specified Employee ” means a specified employee as defined in Section 409A of the Code.

(y) “ Stock Appreciation Right ” means any award consisting of the right to receive payment, for each share of the capital stock of the Company or of any other member of the Company Group subject to such award, of an amount equal to the excess, if any, of the fair market value of such share on the date of exercise of the award over the exercise price for such share granted to a Participant by the Company or any other Company Group member, whether such awards are granted before or after a Change in Control, including any such awards granted in exchange for such awards by a Successor or any other member of the Company Group.

(z) “ Successor ” means any successor in interest to substantially all of the business and/or assets of the Company.

(aa) “ Termination Upon a Change in Control ” means the occurrence of any of the following events:

(1) termination by the Company Group of the Participant’s employment for any reason other than Cause during the Change in Control Period; or

(2) the Participant’s resignation for Good Reason from employment with the Company Group during the Change in Control Period, provided that such resignation occurs within sixty (60) days following the occurrence of the condition constituting Good Reason;

provided, however , that Termination Upon a Change in Control shall not include any termination of the Participant’s employment which is (i) for Cause, (ii) a result of the Participant’s death or Disability, or (iii) a result of the Participant’s voluntary termination of employment other than for Good Reason.

2.2 Construction. Captions and titles contained herein are for convenience only and shall not affect the meaning or interpretation of any provision of the Plan. Except when otherwise indicated by the context, the singular shall include the plural and the plural shall include the singular. Use of the term “or” is not intended to be exclusive, unless the context clearly requires otherwise.

The Board or Committee shall designate those Executive Officers who shall be eligible to become Participants in the Plan. To become a Participant, an Executive Officer so designated by the Committee must execute a Participation Agreement.

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4.1 Equity Awards – Not Assumed or Substituted. Notwithstanding any provision to the contrary contained in any agreement evidencing an Equity Award granted to a Participant, in the event of a Change in Control in which the surviving, continuing, successor, or purchasing corporation or other business entity or parent thereof, as the case may be (the “ Acquiror ” ), does not assume or continue the Company’s rights and obligations under any of the then-outstanding Equity Awards held by the Participant or substitute for any such awards substantially equivalent awards, as the case may be, for the Acquiror’s stock, then the vesting, exercisability and settlement of each such award which is not assumed, continued or substituted for shall be accelerated in full effective immediately prior to but conditioned upon the consummation of the Change in Control. For purposes of this Section 4, an Equity Award shall be deemed assumed or substituted for if, and only if, following the Change in Control, the Equity Award confers the right to receive, subject to the terms and conditions of the stock plan and award agreement pursuant to which such award was granted which are not inconsistent with this Section, for each share of stock of the Company subject to such award immediately prior to the consummation of the Change in Control (and not previously issued in settlement of such award), stock of the Acquiror having a fair market value equal to the fair market value of the consideration (whether stock, cash, other securities or property or a combination thereof) to which a holder of a share of stock of the Company on the effective date of the Change in Control was entitled, such fair market values being determined as of the date of the Change in Control.

4.2 Equity Awards – Assumed or Substituted. Notwithstanding any provision to the contrary contained in any agreement evidencing an Equity Award granted to a Participant, in the event of a Change in Control in which the Acquiror assumes or continues the Company’s rights and obligations under any of the then-outstanding Equity Awards held by the Participant or substituted for any such awards substantially equivalent awards for the Acquiror’s stock, then the vesting, exercisability and settlement of each such award which is assumed, continued or substituted shall on the date of a Termination Upon a Change of Control be accelerated immediately as to such number of shares as would have vested pursuant to the schedule set forth in the agreement or certificate evidencing the Equity Award if the Participant had remained in the employ of the Company Group for twelve (12) months from the date of the Termination Upon a Change in Control.

4.3 Section 409A. The provision, time and manner of payment or distribution of all such compensation and benefits shall be subject to, limited by and construed in accordance with the requirements of Section 409A of the Code, to the extent applicable, including any delay in payments after a Termination Upon a Change in Control of a Specified Employee required by Section 409A.

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In the event of a Participant’s Termination Upon a Change in Control, the Participant shall be entitled to receive the compensation and benefits described in this Section 5. The provision, time and manner of payment or distribution of all such compensation and benefits shall be subject to, limited by and construed in accordance with the requirements of Section 409A of the Code, to the extent applicable, including any delay in payments after a Termination Upon a Change in Control of a Specified Employee required by Section 409A.

5.1 Accrued Obligations. The Participant shall be entitled to receive:

(a) all salary, commissions and accrued but unused vacation earned through the date of the Participant’s termination of employment;

(b) reimbursement within ten (10) business days of submission of proper expense reports of all expenses reasonably and necessarily incurred by the Participant in connection with the business of the Company Group prior to his or her termination of employment; and

(c) the benefits, if any, under any Company Group retirement plan, nonqualified deferred compensation plan, stock purchase or other stock-based compensation plan or agreement (other than any such plan or agreement pertaining to Equity Awards whose treatment is prescribed by Section 5.2(c) below), health benefits plan or other Company Group benefit plan to which the Participant may be entitled pursuant to the terms of such plans or agreements.

5.2 Severance Benefits. Provided that the Participant executes and does not revoke the Release applicable to such Participant at or following the time of the Participant’s Termination Upon a Change in Control, the Participant shall be entitled to receive the following severance payments and benefits:

(a) Salary and Bonus. Within ten (10) business days following the last to occur of (i) the Participant’s termination of employment; (ii) the last day on which the Participant may revoke the Release in accordance with its terms; or (iii) if the Participant is a Specified Employee (but only to the extent the delay in this clause (iii) is required under Section 409A), six months after the date of the Participant’s Separation from Service, the Company shall pay to the Participant in a lump sum cash payment an amount equal to the Participant’s Base Salary Rate multiplied by the number of months in the Benefit Period applicable to the Participant, plus the Participant’s Prior Year Bonus.

Health Insurance Benefits. For the period commencing immediately following the Participant’s termination of employment and continuing for the duration of the Benefit Period applicable to the Participant, the Company shall arrange to provide the Participant and his or her dependents with health insurance benefits (including medical, dental and vision) substantially similar to those provided to the Participant and his or her dependents immediately prior to the date of such termination of employment (without giving effect to any reduction in such benefits constituting Good Reason). Such benefits shall be provided to the Participant without cost to the Participant and at the same coverage level as in effect as of the Participant’s

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termination of employment (without giving effect to any reduction in such benefits constituting Good Reason). The Company may satisfy its obligation to provide a continuation of health insurance benefits by paying the full amount of the Participant’s premiums required under the Consolidated Omnibus Budget Reconciliation Act ( “ COBRA ” ) with respect to