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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

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

                                 SCHEDULE 13G/A

           INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO
              RULES 13d-1 (b), (c) AND (d) AND AMENDMENTS THERETO
                           FILED PURSUANT TO 13d-2 (b)
                                (Amendment No. 2 )*

                           Silicon Laboratories Inc.
- --------------------------------------------------------------------------------
                                (Name of Issuer)

                                  Common Stock
- --------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                   826919102
- --------------------------------------------------------------------------------
                                 (CUSIP Number)

                               December 31, 2002
- --------------------------------------------------------------------------------
             (Date of Event Which Requires Filing of this Statement)

Check the  appropriate box to designate the rule pursuant to which this Schedule
is filed:

      |_|   Rule 13d-1(b)

      | |   Rule 13d-1(c)

      |X|   Rule 13d-1(d)

*The  remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for  any  subsequent   amendment   containing   information  which  would  alter
disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).

                         (Continued on following pages)


                               Page 1 of 19 pages
                            Exhibit Index on Page 17

CUSIP No. 826919102 Page 2 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Austin Ventures IV-A, L.P. ("AV IV-A") - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 315,688 shares, except that AV Partners IV, L.P. ("AVP IV"), the general partner of AV IV-A, may be deemed to have sole power to vote these shares, and Joseph C. Aragona ("Aragona"), Kenneth P. DeAngelis ("DeAngelis"), Jeffery C. Garvey ("Garvey) and William P. Wood ("Wood"), the general partners of AVP IV, may be deemed to have shared power to vote these shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY See response to row 5. OWNED BY -------------------------------------------------------- EACH 7 SOLE DISPOSITIVE POWER REPORTING PERSON 315,688 shares, except that AVP IV, the general partner WITH of AV IV-A, may be deemed to have sole power to dispose of these shares, and Aragona, DeAngelis, Garvey and Wood, the general partners of AVP IV, may be deemed to have shared power to dispose of these shares. -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER See response to row 7. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 315,688 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 0.6% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

CUSIP No. 826919102 Page 3 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Austin Ventures IV-B, L.P. ("AV IV-B") - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 662,312 shares, except that AVP IV, the general partner of AV IV-B, may be deemed to have sole power to vote these shares, and Aragona, DeAngelis, Garvey and Wood, the general partners of AVP IV, may be deemed to have shared power to vote these shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY See response to row 5. OWNED BY -------------------------------------------------------- EACH 7 SOLE DISPOSITIVE POWER REPORTING PERSON 662,312 shares, except that AVP IV, the general partner WITH of AV IV-B, may be deemed to have sole power to dispose of these shares, and Aragona, DeAngelis, Garvey and Wood, the general partners of AVP IV, may be deemed to have shared power to dispose of these shares. -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER See response to row 7. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 662,312 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 1.4% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

CUSIP No. 826919102 Page 4 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) AV Partners IV, L.P. - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 989,854 shares, of which 11,854 are directly owned by AVP IV, 315,688 are directly owned by AV IV-A and 662,312 are directly owned by AV IV-B. AVP IV, the general partner of AV IV-A and AV IV-B, may be deemed to have sole power to vote these shares, and Aragona, DeAngelis, Garvey and Wood, the general partners of AVP IV, may be deemed to have shared power to vote these shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY See response to row 5. OWNED BY -------------------------------------------------------- EACH 7 SOLE DISPOSITIVE POWER REPORTING PERSON 989,854 shares, of which 11,854 are directly owned by WITH AVP IV, 315,688 are directly owned by AV IV-A and 662,312 are directly owned by AV IV-B. AVP IV, the general partner of AV IV-A and AV IV-B, may be deemed to have sole power to dispose of these shares, and Aragona, DeAngelis, Garvey and Wood, the general partners of AVP IV, may be deemed to have shared power to dispose of these shares. -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER See response to row 7. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 989,854 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 2.0% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

CUSIP No. 826919102 Page 5 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Austin Ventures V, L.P. ("AV V") - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 1,555,894 shares, except that AV Partners V, L.P. ("AVP V"), the general partner of AV V, may be deemed to have sole power to vote these shares, and Aragona, DeAngelis, Garvey, John D. Thornton ("Thornton"), Blaine F. Wesner ("Wesner") and Wood, partners of AVP V, may be deemed to have shared power to vote these shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY See response to row 5. OWNED BY -------------------------------------------------------- EACH 7 SOLE DISPOSITIVE POWER REPORTING PERSON 1,555,894 shares, except that AVP V, the general partner WITH of AV V, may be deemed to have sole power to dispose of these shares, and Aragona, DeAngelis, Garvey, Thornton, Wesner and Wood, partners of AVP V, may be deemed to have shared power to dispose of these shares. -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER See response to row 7. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,555,894 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 3.2% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

CUSIP No. 826919102 Page 6 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Austin Ventures V Affiliates Fund, L.P. ("AV V A") - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 167,686 shares, except that AVP V, the general partner of AV V A, may be deemed to have sole power to vote these shares, and Aragona, DeAngelis, Garvey, Thornton, Wesner and Wood, partners of AVP V, may be deemed to have shared power to vote these shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY See response to row 5. OWNED BY -------------------------------------------------------- EACH 7 SOLE DISPOSITIVE POWER REPORTING PERSON 167,686 shares, except that AVP V, the general partner of AV V A, may be deemed to have sole power to dispose of these shares, and Aragona, DeAngelis, Garvey, Thornton, Wesner and Wood, partners of AVP V, may be deemed to have shared power to dispose of these shares. WITH -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER See response to row 7. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 167,686 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 0.3% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

CUSIP No. 826919102 Page 7 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) AV Partners V, L.P. - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 1,723,580 shares, of which 1,555,894 are directly owned by AV V and 167,686 are directly owned by AV V A. AVP V, the general partner of AV V and AV V A, may be deemed to have sole power to vote these shares, and Aragona, DeAngelis, Garvey, Thornton, Wesner and Wood, partners of AVP V, may be deemed to have shared power to vote these shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY See response to row 5. OWNED BY -------------------------------------------------------- EACH 7 SOLE DISPOSITIVE POWER REPORTING PERSON 1,723,580 shares, of which 1,555,894 are directly owned WITH by AV V and 167,686 are directly owned by AV V A. AVP V, the general partner of AV V and AV V A, may be deemed to have sole power to dispose of these shares, and Aragona, DeAngelis, Garvey, Thornton, Wesner and Wood, partners of AVP V, may be deemed to have shared power to dispose of these shares. -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER See response to row 7. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,723,580 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 3.5% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

CUSIP No. 826919102 Page 8 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Joseph C. Aragona - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 127,473 shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY 2,717,834 shares, of which 315,688 are directly owned by OWNED BY AV IV-A, 662,312 are directly owned by AV IV-B, 11,854 EACH are directly owned by AVP IV, 1,555,894 are directly REPORTING owned by AV V, 167,686 are directly owned by AV V A and PERSON 4,400 are directly owned by the Sandra & Joseph Aragona WITH Family Foundation ("Aragona Foundation"), a Texas non-profit corporation. Aragona is a general partner of both AV IV, the general partner of AV IV-A and AV IV-B, and AVP V, the general partner of AV V and AV V A, and is a trustee of the Aragona Foundation, and may be deemed to have shared power to vote these shares. -------------------------------------------------------- 7 SOLE DISPOSITIVE POWER 127,473 shares. -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER 2,717,834 shares, of which 315,688 are directly owned by AV IV-A, 662,312 are directly owned by AV IV-B, 11,854 are directly owned by AVP IV, 1,555,894 are directly owned by AV V, 167,686 are directly owned by AV V A and 4,400 are directly owned by the Aragona Foundation. Aragona is a general partner of both AV IV, the general partner of AV IV-A and AV IV-B, and AVP V, the general partner of AV V and AV V A, and is a trustee of the Aragona Foundation, and may be deemed to have shared power to dispose of these shares. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,845,307 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 5.8% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

CUSIP No. 826919102 Page 9 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Kenneth P. DeAngelis - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 174,138 shares, of which 73,092 are directly owned by DeAngelis and 101,046 are directly owned by DeAngelis, Ltd., a Texas limited partnership, and DeAngelis, the sole general partner of DeAngelis, Ltd., may be deemed to have sole power to vote these shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY 2,713,434 shares, of which 315,688 are directly owned by OWNED BY AV IV-A, 662,312 are directly owned by AV IV-B, 11,854 EACH are directly owned by AVP IV, 1,555,894 are directly REPORTING owned by AV V and 167,686 are directly owned by AV V A. PERSON DeAngelis is a general partner of both AV IV, the WITH general partner of AV IV-A and AV IV-B, and AVP V, the general partner of AV V and AV V A, and may be deemed to have shared power to vote these shares. -------------------------------------------------------- 7 SOLE DISPOSITIVE POWER 174,138 shares, of which 73,092 are directly owned by DeAngelis and 101,046 are directly owned by DeAngelis, Ltd., a Texas limited partnership, and DeAngelis, the sole general partner of DeAngelis, Ltd., may be deemed to have sole power to dispose of these shares. -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER 2,713,434 shares, of which 315,688 are directly owned by AV IV-A, 662,312 are directly owned by AV IV-B, 11,854 are directly owned by AVP IV, 1,555,894 are directly owned by AV V and 167,686 are directly owned by AV V A. DeAngelis is a general partner of both AV IV, the general partner of AV IV-A and AV IV-B, and AVP V, the general partner of AV V and AV V A, and may be deemed to have shared power to dispose of these shares. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,887,572 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 5.9% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

CUSIP No. 826919102 Page 10 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Jeffery C. Garvey - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 0 shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY 2,713,434 shares, of which 315,688 are directly owned by OWNED BY AV IV-A, 662,312 are directly owned by AV IV-B, 11,854 EACH are directly owned by AVP IV, 1,555,894 are directly REPORTING owned by AV V and 167,686 are directly owned by AV V A. PERSON Garvey is a general partner of both AV IV, the general WITH partner of AV IV-A and AV IV-B, and AVP V, the general partner of AV V and AV V A, and may be deemed to have shared power to vote these shares. -------------------------------------------------------- 7 SOLE DISPOSITIVE POWER 0 shares. -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER 2,713,434 shares, of which 315,688 are directly owned by AV IV-A, 662,312 are directly owned by AV IV-B, 11,854 are directly owned by AVP IV, 1,555,894 are directly owned by AV V and 167,686 are directly owned by AV V A. Garvey is a general partner of both AV IV, the general partner of AV IV-A and AV IV-B, and AVP V, the general partner of AV V and AV V A, and may be deemed to have shared power to dispose of these shares. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,713,434 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 5.6% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

CUSIP No. 826919102 Page 11 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) John D. Thornton - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 48,161 shares, of which 3,342 are directly owned by Thornton and 44,819 are directly owned by John Thornton Family I, Ltd. ("Family I"), a Texas limited partnership, and Thornton, the sole general partner of Family I, may be deemed to have sole power to vote these shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY 1,723,580 shares, of which 1,555,894 are directly owned OWNED BY by AV V and 167,686 are directly owned by AV V A. EACH Thornton is a general partner of AVP V, the general REPORTING partner of AV V and AV V A, and may be deemed to have PERSON shared power to vote these shares. WITH -------------------------------------------------------- 7 SOLE DISPOSITIVE POWER 48,161 shares, of which 3,342 are directly owned by Thornton and 44,819 are directly owned by Family I, and Thornton, the sole general partner of Family I, may be deemed to have sole power to dispose of these shares. -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER 1,723,580 shares, of which 1,555,894 are directly owned by AV V and 167,686 are directly owned by AV V A. Thornton is a general partner of AVP V, the general partner of AV V and AV V A, and may be deemed to have shared power to dispose of these shares. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,771,741 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 3.6% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

CUSIP No. 826919102 Page 12 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Blaine F. Wesner - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 87,877 shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY 1,723,580 shares, of which 1,555,894 are directly owned OWNED BY by AV V and 167,686 are directly owned by AV V A. Wesner EACH is a general partner of AVP V, the general partner of AV REPORTING V and AV V A, and may be deemed to have shared power to PERSON vote these shares. WITH -------------------------------------------------------- 7 SOLE DISPOSITIVE POWER 87,877 shares. -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER 1,723,580 shares, of which 1,555,894 are directly owned by AV V and 167,686 are directly owned by AV V A. Wesner is a general partner of AVP V, the general partner of AV V and AV V A, and may be deemed to have shared power to dispose of these shares. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,811,457 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 3.7% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

CUSIP No. 826919102 Page 13 of 19 Pages - -------------------------------------------------------------------------------- 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) William P. Wood - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |X| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen - -------------------------------------------------------------------------------- 5 SOLE VOTING POWER 322,618 shares, of which 222,196 are directly owned by Wood and 100,422 shares are directly owned by Silverton Partners, L.P. ("Silverton"), a Texas limited partnership, and Wood, the sole general partner of Silverton, may be deemed to have sole power to vote these shares. -------------------------------------------------------- NUMBER OF 6 SHARED VOTING POWER SHARES BENEFICIALLY 3,115,781 shares, of which 315,688 are directly owned by OWNED BY AV IV-A, 662,312 are directly owned by AV IV-B, 11,854 EACH are directly owned by AVP IV, 1,555,894 are directly REPORTING owned by AV V, 167,686 are directly owned by AV V A, PERSON 397,947 are directly owned by his spouse and children WITH and 4,400 are directly owned by the Silverton Foundation, a Texas non-profit corporation. Wood is a general partner of AVP IV, the general partner of AV IV-A and AV IV-B, and a partner of AVP V, the general partner of AV V and AV V A, and is a trustee of the Silverton Foundation, and may be deemed to have shared power to vote these shares. -------------------------------------------------------- 7 SOLE DISPOSITIVE POWER 322,618 shares, of which 222,196 are directly owned by Wood and 100,422 shares are directly owned by Silverton, and Wood, the sole general partner of Silverton, may be deemed to have sole power to dispose of these shares. -------------------------------------------------------- 8 SHARED DISPOSITIVE POWER 3,115,781 shares, of which 315,688 are directly owned by AV IV-A, 662,312 are directly owned by AV IV-B, 11,854 are directly owned by AVP IV, 1,555,894 are directly owned by AV V, 167,686 are directly owned by AV V A, 397,947 are directly owned by his spouse and children and 4,400 are directly owned by the Silverton Foundation, a Texas non-profit corporation. Wood is a general partner of AVP IV, the general partner of AV IV-A and AV IV-B, and a partner of AVP V, the general partner of AV V and AV V A, and is a trustee of the Silverton Foundation, and may be deemed to have shared power to dispose of these shares. - -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,438,399 - -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 7.0% - -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTION BEFORE FILLING OUT!

Page 14 of 19 This statement amends the Statement on Schedule 13G filed by Austin Ventures IV-A, L.P., Austin Ventures IV-B, L.P., AV Partners IV, L.P., Austin Ventures V, L.P., Austin Ventures V Affiliates Fund, L.P., AV Partners V, L.P., Joseph C. Aragona, Kenneth P. DeAngelis, Jeffery C. Garvey, John D. Thornton, Blaine F. Wesner and William P. Wood. The foregoing entities and individuals are collectively referred to as the "Reporting Persons." ITEM 4. OWNERSHIP The following information with respect to the ownership of the Common Stock of the issuer by the persons filing this Statement is provided as of December 31, 2002: (a) Amount beneficially owned: See Row 9 of cover page for each Reporting Person. (b) Percent of Class: See Row 11 of cover page for each Reporting Person. (c) Number of shares as to which such person has: (i) Sole power to vote or to direct the vote: See Row 5 of cover page for each Reporting Person. (ii) Shared power to vote or to direct the vote: See Row 6 of cover page for each Reporting Person. (iii) Sole power to dispose or to direct the disposition of: See Row 7 of cover page for each Reporting Person. (iv) Shared power to dispose or to direct the disposition of: See Row 8 of cover page for each Reporting Person.

Page 15 of 19 SIGNATURES After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct. Dated: February 11, 2003 AUSTIN VENTURES IV-A, L.P. /s/ Kevin Kunz By AV Partners IV, L.P., ----------------------------------------- Its General Partner Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact AUSTIN VENTURES IV-B, L.P. /s/ Kevin Kunz By AV Partners IV, L.P., ----------------------------------------- Its General Partner Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact AV PARTNERS IV, L.P. /s/ Kevin Kunz ----------------------------------------- Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact AUSTIN VENTURES V, L.P. /s/ Kevin Kunz By AV Partners V, L.P., ----------------------------------------- Its General Partner Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact AUSTIN VENTURES V AFFILIATES FUND, L.P. /s/ Kevin Kunz By AV Partners V, L.P., ----------------------------------------- Its General Partner Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact AV PARTNERS V, L.P. /s/ Kevin Kunz ----------------------------------------- Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact

Page 16 of 19 JOSEPH C. ARAGONA /s/ Kevin Kunz ----------------------------------------- Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact KENNETH P. DeANGELIS /s/ Kevin Kunz ----------------------------------------- Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact JEFFERY C. GARVEY /s/ Kevin Kunz ----------------------------------------- Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact JOHN D. THORNTON /s/ Kevin Kunz ----------------------------------------- Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact BLAINE F. WESNER /s/ Kevin Kunz ----------------------------------------- Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact WILLIAM P. WOOD /s/ Kevin Kunz ----------------------------------------- Signature Kevin Kunz Chief Financial Officer/Attorney-In-Fact

Page 17 of 19 EXHIBIT INDEX Found on Sequentially Exhibit Numbered Page - ------- ------------- Exhibit A: Agreement of Joint Filing 18 Exhibit B: Reference to Kevin Kunz as Attorney-In-Fact 19

Page 18 of 19 EXHIBIT A Agreement of Joint Filing The Reporting Persons hereby agree that a single Schedule 13G (or any amendment thereto) relating to the Common Stock of Silicon Laboratories Inc. shall be filed on behalf of each of the Reporting Persons. Note that copies of the applicable Agreement of Joint Filing are already on file with the appropriate agencies.

Page 19 of 19 EXHIBIT B REFERENCE TO KEVIN KUNZ AS ATTORNEY-IN-FACT Kevin Kunz has signed the enclosed documents as Attorney-In-Fact. Note that copies of the applicable Power of Attorneys are already on file with the appropriate agencies.