FOURTH MODIFICATION TO REVOLVING CREDIT AND TERM LOAN AGREEMENT

Exhibit 10.5

FOURTH MODIFICATION TO REVOLVING CREDIT

AND TERM LOAN AGREEMENT

This FOURTH MODIFICATION TO REVOLVING CREDIT AND TERM LOAN AGREEMENT (this “Agreement”) made as of the 25th day of September, 2002, by and among INTEGRATED CIRCUIT SYSTEMS, INC., a corporation organized and existing under the laws of the Commonwealth of Pennsylvania, with its chief executive office at 2435 Boulevard of the Generals, Norristown, Pennsylvania 19403, ICST, INC., a corporation organized and existing under the laws of the Commonwealth of Pennsylvania, with its chief executive office at 2435 Boulevard of the Generals, Norristown, Pennsylvania 19403; ICS TECHNOLOGIES, INC., a corporation organized and existing under the laws of the State of Delaware, with its chief executive office at 2435 Boulevard of the Generals, Norristown, Pennsylvania 19403; INTEGRATED CIRCUIT SYSTEMS PTE LTD, a corporation organized and existing under the laws of the Republic of Singapore, with its chief executive office at 1 Kallang Sector, #07-04/06, Kolam Ayer Industrial Park, Singapore 349276; MICRO NETWORKS CORPORATION (“Micro”), a corporation organized and existing under the laws of the State of Delaware, with its chief executive office at 2435 Boulevard of the Generals, Norristown, Pennsylvania 19403; WACHOVIA BANK, NATIONAL ASSOCIATION, with an office at 123 South Broad Street, Philadelphia, Pennsylvania, Pennsylvania 19109; and FLEET NATIONAL BANK, with an office at 7111 Valley Green Road, Fort Washington, Pennsylvania 19034.

RECITALS

WHEREAS, on December 31, 2001, the parties hereto (other than Micro) executed a Revolving Credit and Term Loan Agreement (including any modifications or amendments thereto, the “Loan Agreement”), the terms of which were modified by a Modification to Revolving Credit and Term Loan Agreement dated January 9, 2002, a Second Modification to Revolving Credit and Term Loan Agreement dated as of February 28, 2002, and a Third Modification To Revolving Loan Agreement dated as of June 14, 2002, executed by all parties hereto.

WHEREAS, the terms of the Loan Agreement are incorporated herein and made a part hereof as if fully set forth. Any capitalized term used herein and not otherwise defined herein shall have the meaning ascribed to such term in the Loan Agreement.

WHEREAS, the Borrower has requested that the Banks agree to an additional modification of the Loan Agreement.

NOW THEREFORE, with the above Recitals incorporated herein by reference thereto, the parties hereto, intending to be legally bound hereby, agree as follows:

1. ACKNOWLEDGMENT OF BALANCE. Each Borrower acknowledges that as of September 25th, 2002, the outstanding principal balance of the Loans was $40,000,000.00.

2. MODIFICATION.

Notwithstanding the time for delivery otherwise provided under the Loan Agreement or any other Loan Document, including but not limited to a Post Closing Requirements Agreement dated December 31, 2001, Borrower shall deliver or cause to be delivered timely to the Agent the following payments, documents or instruments, in each instance in form and substance satisfactory to the Agent and the Banks, on or before the time set forth below:

(i) On before September 30, 2002, payment of unreimbursed Expenses incurred by the Banks between June 14, 2002, and September 30, 2002, in the amount of $1569.70; and

(ii) On or before March 16, 2003, a certification issued by the appropriate governmental official or agency of the Commonwealth of Massachusetts that as of the date of such certification Micro is in good standing in the Commonwealth of Massachusetts and that Micro has met all tax liabilities to the Commonwealth of Massachusetts.

The failure by Borrower to supply any of the payments, documents or instruments, in each instance in form and substance satisfactory to the Agent and the Banks, enumerated above on or before the required date shall, absent the written consent of the Agent to the contrary, constitute an Event of Default under the Loan Documents, entitling the Agent and the Banks to exercise the remedies available to them, or any of them, upon an Event of Default as provided in the Loan Documents, including but not limited to the right to terminate the Commitment.

3. ACKNOWLEDGMENTS AND REPRESENTATIONS. The Borrower acknowledges and represents that: (i) except as specifically modified hereby, all terms, covenants, conditions and other provisions (including, but not limited to warrants of attorney for confession of judgment against any Borrower) of the Loan Agreement, all other Loan Documents and any Swap Agreements executed by all or any of them in connection with the Loan Documents are hereby ratified and reaffirmed and continue in full force and effect as of the date hereof as if restated herein in their entirety without any defense, counterclaim, right or claim of set-off; (ii) after giving effect to this Agreement, no default or event that with the passage of time or giving of notice would constitute a default under the Loan Documents has occurred; (iii) all representations and warranties contained in the Loan Documents are true and correct as of this date; (iv) all necessary action to authorize the execution and delivery of this Agreement has been taken; and (v) this Agreement is a modification of an existing obligation and is not a novation and shall not be deemed to diminish, terminate, or satisfy all or any of the Obligations or any Collateral under the Loan Agreement, the Notes or any other Loan Document.

4. COLLATERAL. The Borrower acknowledges and confirms that (i) there have been no changes in the ownership of any Collateral since the Collateral was originally pledged; (ii) the Banks possess an existing, valid first priority security interest and lien in the Collateral; and (iii) such security interest and lien shall secure Borrower’s Obligations to Banks, including any modification of the Notes or Loan Agreement, if any, and all future modifications, extensions, renewals and/or replacements of the Loan Documents.

5. MISCELLANEOUS. This Agreement shall be governed by and construed and enforced as if drafted equally by all parties hereto in accordance with the laws of the Commonwealth of Pennsylvania (without regard to the conflicts of law provisions thereof). This Agreement, the other Loan Documents and any Swap Agreements executed by and between any Borrower and any Bank constitute the sole agreement of the parties with respect to the subject matter hereof and thereof and supersede all oral negotiations and prior writings with respect to the subject matter hereof and thereof. No modification, amendment, termination, or waiver of any provision of this Agreement or any of the Loan Documents shall be binding or enforceable unless in writing, signed by or on behalf of the party against whom enforcement is sought, and otherwise in compliance with Section 9.01 of the Loan Agreement. The illegality, unenforceability or inconsistency of any provision of this Agreement shall not in any way affect or impair the legality, enforceability or consistency of the remaining provisions of this Agreement or the other Loan Documents or any Swap Agreements. This Agreement and the other Loan Documents

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executed by and between any Borrower and any Bank are intended to be consistent. However, in the event of any inconsistencies among this Loan Agreement, as modified hereby, and any of the Loan Documents, the terms of the Loan Agreement shall control. This Agreement may be executed in any number of counterparts and by the different parties on separate counterparts. Each such counterpart shall be deemed an original, but all such counterparts shall together constitute one and the same agreement.

7. PLACE OF EXECUTION AND DELIVERY. Each Borrower hereby certifies that this Agreement and the other Loan Documents were executed in the Commonwealth of Pennsylvania and delivered to the Agent and the Banks in the Commonwealth of Pennsylvania.

IN WITNESS WHEREOF, the undersigned shall be deemed to have signed and sealed this Agreement as of the day and year first above written.

BORROWER

[Signatures continued on next page.]

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WACHOVIA BANK, NATIONAL ASSOCIATION

By:                                                                                       (SEAL)

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FLEET NATIONAL BANK

By:                                                                                       (SEAL)

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