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* CONFIDENTIAL TREATMENT - EDITED COPY

                                                        EXHIBIT 10.19





                  DATED THIS 7TH DAY OF APRIL 1997

 
                              BETWEEN


              CHARTERED SEMICONDUCTOR MANUFACTURING LTD


                                AND


                         OAK TECHNOLOGY, INC.


     -----------------------------------------------------------

                      AMENDMENT AGREEMENT (NO. 2)
                                 TO
                DEPOSIT AGREEMENT DATED 8 NOVEMBER 1995

     -----------------------------------------------------------

           CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR
           BRACKETED PORTIONS WHICH HAVE BEEN FILED
           SEPARATELY WITH THE COMMISSION.               



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                      [ * ] CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR
                            BRACKETED PORTIONS WHICH HAVE BEEN FILED     
                            SEPARATELY WITH THE COMMISSION.                


                          AMENDMENT AGREEMENT (NO. 2)

THIS AMENDMENT AGREEMENT (NO. 2) is made the 7th day of April 1997, by and 
between:-

(1)  CHARTERED SEMICONDUCTOR MANUFACTURING LTD, a company incorporated in 
     Singapore and having its place of business at 60 Woodlands Industrial 
     Park D, Street 2, Singapore 738406 ("CSM"); and

(2)  OAK TECHNOLOGY, INC., a company incorporated in Delaware and having its 
     place of business at 139 Kifer Court, Sunnyvale, CA 94086, United States 
     of America ("Customer").

WHEREAS

(A)  CSM and Customer had entered into a Deposit Agreement dated 8 November 
     1995 (the "Deposit Agreement") for the purpose of Customer depositing 
     certain funds with CSM and to procure CSM to make available to Customer 
     certain wafer manufacturing capacity.

(B)  CSM and Customer had entered into an Amendment Agreement (No. 1) dated 
     25 September 1996 to effect the suspension and variation of certain 
     provisions of the Deposit Agreement upon the terms and conditions set 
     out therein.

(C)  CSM and Customer are entering into this Amendment Agreement (No. 2) to 
     supersede the Amendment Agreement (No. 1) and to effect the suspension 
     and variation of certain provisions of the Deposit Agreement upon the 
     terms and conditions set out herein.

NOW THEREFORE, in consideration of the foregoing and the mutual covenants 
contained herein, the Parties agree as follows:-

1.   INTERPRETATION

     All terms and references used in the Deposit Agreement and which are 
     defined or construed in the Deposit Agreement but are not defined or 
     construed in this Amendment Agreement (No. 2) shall have the same 
     meaning and construction in this Amendment Agreement (No.2).

2.   AMENDMENT AGREEMENT (NO. 1) SUPERSEDED

     With effect from the date of this Amendment Agreement (No. 2), the terms 
     and conditions of Amendment Agreement (No. 1) shall be superseded by the 
     terms


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                      [ * ] CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR
                            BRACKETED PORTIONS WHICH HAVE BEEN FILED     
                            SEPARATELY WITH THE COMMISSION.                

    and conditions of this Amendment Agreement (No. 2) and shall cease to 
    have any force or effect.

3.  CONDITION PRECEDENT

    The provisions of Clause 5 herein, are subject to and conditional upon 
    each of the following condition precedents being satisfied, and the 
    provisions of Clause 5 herein shall cease to have any force or effect if 
    any of the following condition precedents are not satisfied:

    3.1  by [ * ] Customer shall tape out a [ * ] Logic "[ * ]" product 
         ("[ * ] Product") at CSM's wafer fabrication facilities situated in 
         Singapore; and

    3.2  During the period commencing from the date of this Amendment 
         Agreement (No. 2) to [ * ], Customer shall place purchase orders 
         with CSM and take delivery of an aggregate total of [ * ] wafers for 
         any [ * ] logic products (including but not limited to the "[ * ]" 
         Product) from CSM; and 

    3.3  by [ * ], Customer shall tape out a [ * ] Logic product ("[ * ] 
         Logic Product") at CSM's wafer fabrication facilities situated in 
         Singapore.

4.  EFFECTIVE DATE

    The Parties agree that the term "Effective Date" shall refer to [ * ], if 
    Customer fulfills each of the condition precedents set out in Clauses 
    3.1, 3.2 and 3.3 above.

5.  SUSPENSION OF CERTAIN TERMS OF DEPOSIT AGREEMENT

    The Parties agree that subject to the terms of this Amendment Agreement 
    (No. 2) and provided that each of the condition precedents set out in 
    Clauses 3.1, 3.2 and 3.3 above are satisfied, for the period from the 
    Effective Date until [ * ] (hereinafter known as the "Suspension 
    Period"), certain provisions of the Deposit Agreement shall be suspended 
    and shall not apply to the Parties and in place of the same, the 
    following provisions shall apply during the Suspension Period instead:

    5.1  CLAUSE 1 (THE DEPOSIT)

         (a)  Clause 1.1 shall be suspended and in its place, the following 
              provision shall apply:


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                      [ * ] CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR
                            BRACKETED PORTIONS WHICH HAVE BEEN FILED     
                            SEPARATELY WITH THE COMMISSION.                



              "1.1  As at the date of this Agreement, Customer has deposited
                    with CSM the sum of [ * ] (the "Deposit").

         (b)  Clause 1.2 shall be suspended.

         (c)  Clause 1.3 shall be suspended and in its place, the following 
              provision shall apply:

              "1.3  Upon the expiry of the term of this Agreement or the 
                    earlier termination thereof in accordance with Clause 6
                    or Clause 7.2, CSM will return to Customer the Deposit,
                    without interest and subject to any deductions or refunds 
                    made by CSM pursuant to the terms of this Agreement."

    5.2  CLAUSE 2 (CSM SUPPLY COMMITMENT)

         (a)  Clause 2.1 shall be suspended and in its place, the following 
              provision shall apply:

              "2.1  CSM agrees that for the duration of the Suspension Period,
                    CSM will make available to Customer wafer manufacturing 
                    capacity for [ * ] wafers of a sufficient quantity so that 
                    Customer is able to utilise the [ * ] Deposit amount given
                    the credit rate set forth in Clause 5.4 below during the
                    Suspension Period."

         (b)  Clause 2.3 shall be suspended and in its place, the following 
              provision shall apply:

              "2.3  CSM reserves the right to adjust the pricing of wafers to 
                    be supplied by CSM from time to time depending on 
                    prevailing market conditions, provided however that CSM 
                    shall give Customer not less than 3 months' prior written 
                    notice of such adjustment. In any event, the price of 
                    wafers supplied to Customer shall be based upon then 
                    prevailing market conditions as compared to prices 
                    provided by other independent wafer foundries for similar 
                    products, processes and quantities. An "independent wafer 
                    foundry" means a company which engages in the business of 
                    manufacturing semiconductor integrated circuits for sale 
                    only to third parties. Accordingly, a company which 
                    manufactures semiconductor integrated circuits for use in 
                    its own proprietary semiconductor


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                      [ * ] CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR
                            BRACKETED PORTIONS WHICH HAVE BEEN FILED     
                            SEPARATELY WITH THE COMMISSION.                



                    products or end-products is not considered an independent 
                    wafer foundry."

    5.3  CLAUSE 3 (CUSTOMER LOADING COMMITMENT)

         Clauses 3.1, 3.2 and 3.3 shall be suspended.

    5.4  CLAUSE 4 (LIQUIDATED DAMAGES)

         Clauses 4.1, 4.2, 4.3, 4.4 and 4.5 shall be suspended.

    5.5  CLAUSE 5 (SET OFF AND MAINTENANCE OF DEPOSIT)

         Clauses 5.1, 5.2 and 5.3 shall be suspended and in their place, the 
         following provisions shall apply:

         "5.1  CSM shall be entitled to deduct from and set-off against the 
               Deposit, any payment falling due and remaining unpaid by 
               Customer under the Foundry Agreement.

         5.2   At the end of each calendar quarter, CSM shall issue a written 
               notice to Customer stating the amount of the overdue payments 
               and Customer shall pay the relevant sum to CSM within 30 days 
               of the date of such notice, so as to maintain the Deposit at 
               [ * ] less such amounts that may have been refunded by CSM to 
               Customer pursuant to Clause 5.4 below.

         5.3   CSM's right of deduction and set-off pursuant to Clause 5.2 
               shall be in addition to CSM's right to claim the aforesaid 
               overdue payments separately as a debt due from Customer and 
               shall not in any way prejudice such right or any other rights 
               or remedies which CSM may have at law or in equity.

         5.4   For the period:

               (a)  the date of this Amendment Agreement (No. 2) to [ * ], for
                    every [ * ] logic [ * ] wafer that CSM ships to Customer, 
                    CSM will refund to Customer the sum of [ * ] from the 
                    Deposit within 30 days from [ * ];

               (b)  [ * ] to [ * ] (i) for every [ * ] Logic [ * ] wafer (up 
                    to [ * ] wafers) that CSM ships to Customer, Customer is 
                    entitled to a wafer credit of the 


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                      [ * ] CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR
                            BRACKETED PORTIONS WHICH HAVE BEEN FILED     
                            SEPARATELY WITH THE COMMISSION.                


                    sum of [ * ] from the Deposit; and (ii) for every [ * ] 
                    Logic [ * ] wafer in excess of [ * ] wafers that CSM 
                    ships to Customer, Customer is entitled to a wafer credit 
                    of the sum of [ * ] from the Deposit;

               (c)  [ * ] to [ * ], (i) for every [ * ] Logic [ * ] wafer (up 
                    to [ * ] wafers) that CSM ships to Customer, Customer is 
                    entitled to a wafer credit of the sum of [ * ] from the 
                    Deposit; and (ii) for every [ * ] Logic [ * ] wafer in 
                    excess of [ * ] wafers that CSM ships to Customer, 
                    Customer is entitled to a wafer credit of the sum of [ * ]
                    from the Deposit;

               For the purpose of clarity, the provisions set out in Clauses
               5.4(b) and (c) above are represented in the following table:

               ---------------------------------------------------------------
                   Period              No. of wafers          Amount
                                        purchased             deductible
               ---------------------------------------------------------------
                [ * ] to [ * ]      [ * ] to [ * ]            [ * ] per wafer
                [ * ]
               ---------------------------------------------------------------
                                    [ * ] and more            [ * ] per wafer
               ---------------------------------------------------------------
                [ * ] to [ * ]      [ * ] to [ * ]            [ * ] per wafer
                [ * ]
               ---------------------------------------------------------------
                                    [ * ] and more            [ * ] per wafer
               ---------------------------------------------------------------
                
               (d)  The wafer credits referred to in Clauses 5.4(b) and (c) 
                    above will be paid out of the Deposit. CSM shall issue 
                    Customer a credit note for such wafer credits within 30 
                    days of the date of the invoices for [ * ] Logic [ * ] 
                    wafer purchases made in accordance with Clauses 5.4(b) 
                    and (c), save that for any [ * ] Logic [ * ] wafer 
                    purchases made by Customer for the period from [ * ] to 
                    [ * ] pursuant to Clause 5.4(b), CSM shall issue a credit 
                    note for the wafer credits relating to such purchases 
                    within 30 days of [ * ];

               (e)  In no event will the aggregate amount of the refunds or 
                    wafer credits granted to Customer pursuant to the 
                    provisions set out in Clauses 5.4(a), (b) or (c) above 
                    exceed the existing Deposit of [ * ]; and

               (f)  In the event that Embedded Memory technology is available 
                    at CSM's wafer fabrication facilities situated in 
                    Singapore, Customer is entitled to elect to purchase


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                      [ * ] CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR
                            BRACKETED PORTIONS WHICH HAVE BEEN FILED     
                            SEPARATELY WITH THE COMMISSION.                


                    wafers in either [ * ] Logic or [ * ] Embedded Memory or 
                    both, on the provisions set out in Clauses 5.4(b) and (c) 
                    above. CSM shall use best efforts to make CSM's [ * ] 
                    libraries available to Customer and Customer shall be 
                    permitted to access and utilise CSM's [ * ] libraries 
                    provided that such access and utilisation shall be only to
                    the extent that is permitted by the relevant licensors 
                    who may have granted CSM a license over such libraries."

    5.6  CLAUSE 6 (TERM AND TERMINATION)

         Clauses 6.1(a), (b) and (c) shall be suspended.

    5.7  ANNEX A (PAYMENT SCHEDULE)

         Annex A shall be suspended.

    5.8  ANNEX B (CSM SUPPLY COMMITMENT/CUSTOMER LOADING COMMITMENT)

         Annex B shall be suspended except as provided in Clause 2.1 of the 
         Deposit Agreement.

    5.9  In addition to the suspension of Clause 1.1 and Annex A of the 
         Deposit Agreement, provided that each of the condition precedents 
         set out in Clause 2 of this Amendment Agreement (No. 2) are 
         satisfied, the Deposit amounts due and payable by Customer on 2 
         January 1996, 2 January 1997 and 2 January 1998 as specified in 
         Annex A, shall be suspended for the duration of the Suspension 
         Period.

    5.10 The provisions of Clauses 11.1, 11.2 and 11.3 of the Deposit 
         Agreement are subject to the provisions of this Amendment Agreement 
         (No. 2).

6.  ASSISTANCE TO TAPE OUT

    CSM shall use its best efforts to provide reasonable assistance to 
    Customer to tape out [ * ] logic products, as well as a [ * ] Logic 
    Product at CSM's wafer fabrication facilities situated in Singapore.

7.  TERMINATION OF DEPOSIT AGREEMENT

    7.1  Provided that each of the condition precedents in Clauses 3.1, 3.2 
         and 3.3 above have been fulfilled, the Deposit Agreement shall be 
         automatically


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                      [ * ] CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR
                            BRACKETED PORTIONS WHICH HAVE BEEN FILED     
                            SEPARATELY WITH THE COMMISSION.                


         terminated on [ * ] if the Deposit is reduced to zero by [ * ] as a 
         result of Customer obtaining refunds or utilising the Deposit 
         towards payment of wafers in accordance with the provisions in 
         Clause 5.5 above.

    7.2  In the event the Deposit is not reduced to zero by [ * ], all the 
         terms of the Deposit Agreement shall apply for the period [ * ] to 
         the expiry of the Deposit Agreement, in full force and effect 
         without any amendments or suspensions.

8.  SAVING AND INCORPORATION

    8.1  Save as expressly varied by the terms of this Amendment Agreement 
         (No. 2), the terms and conditions of the Deposit Agreement shall 
         continue to be in full force and effect in all other respects.

    8.2  The Deposit Agreement and this Amendment Agreement (No. 2) shall be 
         construed as one document and this Amendment Agreement (No. 2) shall 
         be deemed to be part of the Deposit Agreement. Where the context so 
         permits, references in the Deposit Agreement and in this Amendment 
         Agreement (No. 2) to "the Deposit Agreement" or "this Agreement" 
         shall be read and construed as references to the Deposit Agreement 
         as amended and supplemented by this Amendment Agreement (No. 2).

9.  GOVERNING LAW

    This Amendment Agreement (No. 2) shall be governed by and construed in 
    accordance with the laws of Singapore. The Parties hereby irrevocably 
    submit to the non-exclusive jurisdiction of the courts of Singapore.

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IN WITNESS WHEREOF the Parties have hereunto entered into this Amendment 
Agreement (No. 2) the date first above written.


Signed by Tan Bock Seng,      )
President & CEO,              )
CHARTERED SEMICONDUCTOR       )
MANUFACTURING LTD             )    /s/ Tang Bock Seng
in the presence of:           ) --------------------------------


    /s/ Patricia Yong
-----------------------------------
Name:  Patricia Yong, Legal Officer


Signed by David D. Tsang,     )
President,                    )
OAK TECHNOLOGY, INC.          )   /s/ David D. Tsang
in the presence of:           ) --------------------------------



-----------------------------------
Name:  Shawn M. Soderberg,
       General Counsel