Exhibit 4.6

                          [LOGO] ZARLINK SEMICONDUCTOR

                           ZARLINK SEMICONDUCTOR INC.
                    1991 STOCK OPTION PLAN FOR KEY EMPLOYEES
                           AND NON-EMPLOYEE DIRECTORS

                  AS AMENDED DECEMBER 7, 2001 AND JULY 24, 2007

      1. Purpose. The Zarlink  Semiconductor Inc. 1991 Stock Option Plan for Key
Employees  and  Non-Employee  Directors  (the "Plan") is intended to attract and
retain  highly  qualified  employees  and  non-employee  directors  who  will be
motivated toward the success of Zarlink  Semiconductor  Inc. (the "Company") and
to  encourage  share  ownership  in the  Company by certain  key  employees  and
non-employee directors of the Company and its subsidiaries.

      2.  Number of Common  Shares to be  Offered.  The  shares  subject  to the
options to be granted  under  this Plan  shall be Common  Shares of the  Company
("Common Shares").  The maximum number of Common Shares that may be issued under
this Plan shall not exceed  20,227,033 Common Shares and no employee (as defined
below) shall hold options to purchase more than 5% of the total number of Common
Shares issued and outstanding from time to time. In addition, the maximum number
of Common  Shares in respect  of which  options  may be granted to  non-employee
directors  during any fiscal year of the Company  shall be 20,000 per  director.
Upon the  expiration,  surrender  or  termination,  in  whole or in part,  of an
unexercised  option, the Common Shares subject to such option shall be available
for other options to be granted from time to time under this Plan.

      3. Limits with Respect to Insiders.

      (a) The maximum  number of Common Shares  issuable to insiders (as defined
in the Securities Act (Ontario) and the rules of any applicable  stock exchange)
("insiders" and each an "insider"),  at any time,  under this Plan and any other
security based  compensation  arrangement of the Company is 10% of the number of
Common Shares outstanding.

      (b) The maximum number of Common Shares issued to insiders under this Plan
and any other security based compensation arrangement of the Company, within any
one-year period, is 10% of the number of Common Shares outstanding.

      4. Terms and Conditions of Option.

      (a) Employees  Eligible to Receive  Options.  The individuals who shall be
eligible  to receive  options  under this Plan shall be such key  employees  and
non-employee  directors  of the Company and its  subsidiaries  as the  Committee
("Committee"  described  in  Section 6 of this  Plan)  from  time to time  shall
determine.  Any reference  herein to "employee(s)"  shall include  "director(s)"
except to the extent


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that specific terms of the Plan apply to directors.  More than one option may be
granted to the same employee.

      (b) Option Price.  The price at which Common Shares may be purchased under
the Plan shall be as  determined  by the  Committee  on the date of grant of the
option (the "Grant  Date"),  provided  however,  that such price may not be less
than the average of the market price of the Common  Shares on The Toronto  Stock
Exchange for the five trading day period  immediately  preceding the Grant Date.
For the purpose hereof, "market price" shall mean:

            (i) the  average of the high and low prices of the Common  Shares on
The Toronto Stock Exchange on a trading day, or

            (ii) if there was no trade  for the  Common  Shares  on the  Toronto
Stock  Exchange on any  particular  relevant  trading day, then the market price
shall be the average of the bid and ask quotations for the Common Shares on such
relevant trading day on the exchange.

      (c) Option  Period.  Subject to Section 4(h) and 6, each option for Common
Shares granted under the Plan (the "Option Shares") may be exercised at any time
or from time to time as follows:

            (i) in the case of  employees  (except for  executive  officers  and
non-employee  directors)  to whom an  option is  granted  under the Plan for the
first time,  25% of the Option  Shares  become vested and may be exercised as of
and  following  the first  anniversary  of the date of grant of such option and,
thereafter,  2.08% of the Option  Shares become vested and may be exercised on a
monthly basis as of the last day of each month  following the first  anniversary
of the date of grant of such option until the 48th month after the date of grant
of such option, and

            (ii) in the case of  employees  (except for  executive  officers and
non-employee directors) who are already optionholders at the time of grant of an
additional  option under the Plan,  2.08% of the Option Shares become vested and
may be exercised on a monthly basis as the last day of each month  following the
date of grant of such  option  until the 48th  month  after the date of grant of
such  option,  or at  such  other  time or  times  as may be  determined  by the
Committee at the time of grant.

On the date determined by the Committee at the time of grant which occurs within
a maximum  of six years  following  the date of grant of an  option,  the option
shall expire and terminate and be of no further force or effect whatsoever.

      (d) Methods of Payment.  The employee  from time to time during the option
period may elect to purchase all or part of the Option Shares which the employee
is  entitled to  purchase  by lump sum  payment by  delivering  to the Company a
completed  stock option  purchase  form.  Such form shall  specify the number of
Option  Shares the  employee  desires to purchase  and shall be  accompanied  by
payment in full of the


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purchase  price for such Option Shares.  Payment can be made by cash,  certified
cheque, bank draft or money order payable to the Company.

      (e)  Withholding.  No Option  Shares  shall be issued by the Company to an
employee until  appropriate  arrangements  have been made for the payment of any
amounts which may be required under any law, regulation, rule or otherwise to be
withheld  or  paid by the  Company  with  respect  thereto,  including,  without
limitation, withholding the transfer of a portion of the shares of the Company's
stock  otherwise  issuable in order to satisfy all or a portion of the  required
withholdings or payments.

      (f) Termination of Employment of an Employee. Subject to Sections 4(g) and
4(j),  in the  event  that an  employee's  employment  with the  Company  or any
subsidiary is terminated prior to the expiry date of the employee's  option, the
employee's  option may be  exercised,  at anytime  during the period which is no
more than 90 days  following  the date the  employee's  employment is terminated
(but in no event after the expiry date of such option), as to such of the Option
Shares in respect of which such option has not previously  been  exercised,  but
only to the  extent  that  the  employee  was  entitled  at his  termination  of
employment to purchase such Option Shares then  exercisable  pursuant to Section
4(c) above;  provided,  however, that in the event the employment of an employee
who has received an option under the Plan is terminated as set forth above,  the
Board of Directors of the Company may, in its own discretion, amend the terms of
any option to permit the employee to exercise such options as if such employee's
employment  had not been  terminated  (provided  that the exercise  period shall
terminate on the earlier of (i) three years  following  the date the  employee's
employment is terminated and (ii) the expiry date of such option).  For purposes
of this Plan, the transfer of an employee's  employment to the Company or to any
subsidiary of the Company shall not be considered a termination of employment.

      (g)  Termination  of Employment of an Employee for Cause.  Notwithstanding
any other  term or  condition  of the  Plan,  in the  event  that an  employee's
employment  with the Company or any  subsidiary  is  terminated  for cause,  the
employee's  option  shall be  immediately  terminated  and such  employee  shall
forfeit  all rights  thereto as of the date of  personal  delivery  of a written
notice  confirming such  termination and the requirement to exercise options and
not after,  as to such of the Option  Shares in respect of which such option has
not previously been exercised.

      (h) Automatic  Acceleration of Exercise Periods for Non-Employee Directors
Upon Change of Control.  In the event of a change of control (whether in fact or
in law) of the Company which results in a non-employee  director being replaced,
the  periods set forth under  Section  4(c) shall be waived with  respect to the
options  then held by such  non-employee  director  in order to permit  the full
exercise of all outstanding options then held by such person.

      (i) Resignation of a Director.  In the event that a non-employee  director
ceases  to  act  as a  director  of  the  Company,  all  options  held  by  such
non-employee  director,  which are then exercisable  pursuant to Section 4(c) or
4(h),  as the case may


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be, may be exercised within 180 days following the announcement of the quarterly
results next  following the date of  resignation of such person (but in no event
after the expiry date of such option).

      (j) Rights in the Event of an Employee's  Death. In the event of the death
or the  permanent  disability  of an  employee  while in the  employment  of the
Company or any  subsidiary  and on or prior to the expiry date of the employee's
option and  provided  such  employee  shall have been in the  employment  of the
Company or any  subsidiary  for at least  five  years  prior to the date of such
employee's  death  or  permanent  disability,  the  exercise  date of 50% of the
employee's  option which is not exercisable on the date of such employee's death
or permanent disability,  shall be accelerated so that the employee's option may
be exercised by the employee's legal personal representative(s) or the employee,
as applicable,  at any time after the date of the employee's  death or permanent
disability  up to and  including  (but  not  after)  a date  which  is one  year
following the date of the employee's  death or permanent  disability  (but in no
event  after the  expiry  date of such  option),  as to any or all of the Option
Shares in respect of which such option has not previously been exercised. In the
event that such employee shall have been in the employment of the Company or any
subsidiary for at least ten years prior to the date of such employee's  death or
permanent  disability,  the exercise date of 100% of the employee's option which
is not  exercisable  on such  date  shall be so  accelerated.  For the  purposes
hereof,  "permanent  disability"  has the  meaning  assigned to that term in the
Zarlink Employee Canadian Benefits Plan, as amended from time to time.

      (k) No  Employment  Right.  Nothing  in this Plan  shall  confer  upon the
employee  the right to continue in the employ of the Company or interfere in any
way with the right of the Company to terminate the employee's  employment at any
time and for any reason.

      (l)  No  Shareholder  Rights.  An  employee  shall  have  no  rights  as a
shareholder  with respect to any Option Shares covered by the employee's  option
until the date of the valid  issuance  of such shares to the  employee  and only
after such shares are fully paid for. No  adjustment  will be made for dividends
or other  distributions or rights for which the record date is prior to the date
of such issuance.

      (m) Transfer and Assignment. The employee's rights with respect to options
granted  under the Plan are not  assignable or  transferable  by the employee or
subject to any other  alienation,  sale,  pledge or encumbrance by such employee
other than by will or by the laws of descent and  distribution  or pursuant to a
qualified domestic relations order as defined by the U.S. Internal Revenue Code.
Therefore the options are exercisable during the employee's lifetime only by the
employee.  The  obligations  of each  employee  shall be  binding  on his heirs,
executors and administrators.

      (n) Compliance with United States Securities and Other Laws. Option Shares
may be purchased  only if the Company  determines  to and obtains the  necessary


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approvals  to sell its Common  Shares to  employees  who are  citizens of or are
employed in the United  States under  applicable  United States  securities  and
other laws.

      5.  Adjustments.  Upon the  happening of any of the following  events,  an
employee's  rights  with  respect  to  options  granted  under the Plan shall be
adjusted as hereinafter provided.

      (a) In the event of any  subdivision,  redivision  or change of the Common
Shares into a greater  number of shares at any time, or in the case of the issue
of shares of the Company to the holders of its outstanding  Common Shares by way
of stock  dividend  or  stock  dividends  (other  than an  issue  of  shares  to
shareholders  pursuant to their exercise of options to receive  dividends in the
form of shares of the Company in lieu of cash dividends  declared payable in the
ordinary  course by the  Company  on its  Common  Shares),  the number of Common
Shares  deliverable  by the  Company  upon the  exercise  of an option  shall be
appropriately  increased  proportionately,  and appropriate adjustments shall be
made in the purchase price per share to reflect such subdivision,  redivision or
change.

      (b) In the event of any  consolidation or change of the Common Shares into
a lesser number of shares at any time,  the number of Common Shares  deliverable
by the Company upon the exercise of an option shall be  appropriately  decreased
proportionately, and appropriate adjustments shall be made in the purchase price
per share to reflect such consolidation.

      (c) In the  event  of any  reclassification  or  reclassifications  of the
Common Shares,  at any time an employee shall accept, at the time of purchase of
Option  Shares,  in lieu of the number of Common  Shares in respect of which the
option to  purchase is being  exercised,  the number of shares of the Company of
the  appropriate  class or classes as the employee would have been entitled as a
result  of  such  reclassification  or  reclassifications  had the  option  been
exercised before such reclassification or reclassifications.

      (d) If the Company is to be amalgamated with or acquired by another entity
in a  merger,  sale  of all or  substantially  all of the  Company's  assets  or
otherwise  (an  "Acquisition"),  the  Committee or the Board of Directors of any
entity  assuming the  obligations of the Company under the Plan (the  "Successor
Board"), shall, as to outstanding options, either (i) make appropriate provision
for the  continuation  of such options by substituting on an equitable basis for
the shares then subject to such options the  consideration  payable with respect
to the outstanding  Common Shares in conjunction with the  Acquisition;  or (ii)
upon  written  notice  to the  employees,  provide  that  all  options  must  be
exercised, to the extent then exercisable,  within a specified number of days of
the date of such notice, at the end of which period the options shall terminate;
or (iii)  terminate  all options in  exchange  for a cash  payment  equal to the
excess of the fair market  value of the shares  subject to such  options (to the
extent then exercisable) over the exercise price thereof.


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      (e) In the  event  of  the  proposed  dissolution  or  liquidation  of the
Company,  each option will terminate  immediately  prior to the  consummation of
such proposed action or at such other time and subject to such other  conditions
as shall be determined by the Committee.

      (f) Except as  expressly  provided  herein,  no issuance by the Company of
shares of any class, or securities  convertible into shares of any class,  shall
affect,  and no adjustment by reason  thereof shall be made with respect to, the
number or price of shares subject to options.  No adjustments  shall be made for
dividends paid in cash or in property other than securities of the Company.

      (g) No  fractional  shares shall be issued under the Plan and the employee
shall receive from the Company cash in lieu of such fractional shares.

      (h)  Upon  the  happening  of any of the  foregoing  events  described  in
subparagraphs  (a),  (b), (c) or (d) above,  the class and  aggregate  number of
shares set forth in  paragraph  2 that are subject to options  which  previously
have  been  or  subsequently  may be  granted  under  the  Plan  shall  also  be
appropriately  adjusted to reflect the events  described in such  subparagraphs.
The Committee or the Successor Board shall determine the specific adjustments to
be made under this  paragraph 5 and,  subject to paragraph 6, its  determination
shall be conclusive.

      6. Administration. This Plan shall be administered by the Compensation and
Human  Resources  Development  Committee  (the  "Committee").   Members  of  the
Committee  shall be appointed by the Board of Directors of the Company and shall
serve as such at the pleasure of the Board of  Directors.  The  Committee  shall
have full power and  authority to designate  those key  employees of the Company
and its  subsidiaries  who are to be granted options under this Plan, the number
of options to be granted to each such key  employee  and  otherwise to interpret
and construe the terms and  conditions  of the options  granted under this Plan.
Without  limiting the  generality of the powers and  discretions  granted to the
Committee herein,  the Committee may determine that any option granted under the
Plan shall include provisions which accelerate the date on which an option shall
become  exercisable  upon the  happening  of such  events as the  Committee  may
determine and as may be prescribed in the applicable options agreement.  Without
limiting the  generality of the foregoing the Committee may determine  that such
acceleration  should  occur in the event of an actual or  anticipated  change of
effective control of the Company,  or in the event of other fundamental  changes
to the Company or its business or affairs.  Any  determination  by the Committee
shall be final  and  conclusive  unless  otherwise  determined  by the  Board of
Directors of the Company,  and in any such event such determination of the Board
of Directors shall be final and  conclusive.  The day-to-day  administration  of
this Plan may be delegated to such  officers and  employees of the Company or of
any  subsidiary  of the Company as the  Committee in its sole  discretion  shall
determine.


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      7.  Variation  of  Grant,  Amendment  and  Discontinuance.  The  Board  of
Directors  shall have the right to amend,  modify or terminate  this Plan or any
option granted under this Plan at any time without  notice;  provided,  however,
that

      (a) any such amendment or  modification  of this Plan which  increases the
total  number of Common  Shares which are to be offered  under this Plan,  as so
amended or modified, shall be approved by the shareholders of the Company,

      (b) any such  amendment  or  modification  of this Plan may not modify the
rights of employees with respect to options granted under the Plan without their
previous consent and any required regulatory approvals,

      (c) any  program  implemented  by the Company at any time and from time to
time to provide for the exchange of any option granted under this Plan for other
options under this Plan shall be approved by the shareholders of the Company,

      (d) any  reduction  in the price at which  Common  Shares may be purchased
under the Plan (except in connection  with an adjustment to the share capital in
accordance with Section 5 hereof) or any  cancellation and reissuance of options
shall be approved by the shareholders of the Company,

      (e) an  extension  of the  original  expiry  date of an  option  shall  be
approved by the shareholders of the Company,

      (f) any  increase  of the  maximum  number of Common  Shares  issuable  to
insiders of the Company  pursuant to the exercise of options  under the Plan and
any  other  security-based  compensation  arrangement  of the  Company  shall be
approved by the shareholders of the Company,

      (g) any  amendment  to the maximum  number of Common  Shares in respect of
which options may be granted to non-employee directors during any fiscal year of
the Company shall be approved by shareholders of the Company,

      (h) any amendment to the terms of this Plan which would permit  options to
be transferable or assignable (other than in the limited circumstances described
in Section 4(m) hereof) shall be approved by shareholders of the Company, and

      (i) any  amendment  or  modification  of this Plan will be  subject to the
prior approval of the Toronto Stock  Exchange and any regulatory  body requiring
similar approval.

The Board of Directors of the Company shall have the full power and authority to
approve  any other  amendments  relating  to the Plan or any  option  previously
granted without further approval of the  shareholders of the Company,  including
if such amendments relate to, among other things:


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      (a) any amendment to the  eligibility  for, and  limitations or conditions
on, participation in the Plan;

      (b) any  amendment  to any  terms  relating  to the grant or  exercise  of
options,  including,  but not limited  to, the terms  relating to the amount and
payment of the exercise  price (other than a reduction in the price of an option
(except in connection with an adjustment to the share capital in accordance with
Section 5 hereof)),  vesting, expiry,  adjustment of options, or the addition or
amendment  of  terms  relating  to the  provision  of  financial  assistance  to
employees or of any cashless exercise features;

      (c)  any  amendment  to the  Plan to  permit  the  grant  of  deferred  or
restricted  share units  under the Plan or to add or amend any other  provisions
which  result in employees  receiving  securities  of the Company  while no cash
consideration is received by the Company;

      (d) any change that is necessary  or  desirable to comply with  applicable
laws, rules or regulations of any  governmental  entity,  agency,  department or
authority or any applicable stock exchange;

      (e) any correction or rectification of any ambiguity, defective provision,
error or omission in the Plan or in any option; and

      (f) any amendment of the terms relating to the administration of the Plan,

provided such amendment does not result in significant or unreasonable  dilution
in the  Company's  outstanding  securities,  or in any  additional  benefits  to
employees,  particularly  insiders,  at the expense of the Company and its other
shareholders.

      8.  Termination  of the  Plan.  The  Plan  shall  remain  effective  until
terminated  by  the  Board  of  Directors  of  the  Company  provided  that  the
termination of the Plan shall have no effect on outstanding options, which shall
remain  in  accordance  with  their  terms  and  conditions  and the  terms  and
conditions of the Plan.

      9. No Corporate Action Restriction. Nothing contained in the Plan shall be
construed to prevent or preclude the Company  from taking any  corporate  action
which is  deemed  by the  Company  to be  appropriate  or in its best  interest,
whether  or not such  action  would  have an  adverse  effect on the Plan or any
option award made under the Plan. No employee, beneficiary or other person shall
have any claim against the Company as a result of such corporate action.

      10.  Governing Law. The Plan and the options  granted under the Plan shall
be construed in  accordance  with and be governed by the laws of the Province of
Ontario and the laws of Canada applicable therein.

Dated this 24th day of July, 2007.


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