Exhibit 10.64

ADDENDUM #4 TO

ADVANCE PAYMENT AND PURCHASE AGREEMENT

THIS ADDENDUM #4 TO ADVANCE PAYMENT AND PURCHASE AGREEMENT (this “4th Addendum”)
is entered into by and between Lattice Semiconductor Corporation, having an
office at 5555 NE Moore Court, Hillsboro, OR 97124 (“Lattice”) and Fujitsu
Microelectronics Limited, having an office at Shinjuku Dai-ichi Seimei Bldg, 7-1
Nishi-Shinjuku 2-chome, Shinjuku-ku, Tokyo 163-0722, Japan (“FML”) and Fujitsu
Microelectronics America, Inc., having an office at 1250 East Arques Avenue,
M/S333 Sunnyvale, CA 94088-3470, USA (“FMA”) and is effective upon the last date
of signature hereto (“4th Addendum Effective Date”).

WHEREAS, Lattice and Fujitsu Limited (“Fujitsu”) have entered into the following
agreement and addenda:

 

(i) an ADVANCE PAYMENT AND PURCHASE AGREEMENT dated September 10, 2004 (as
amended by the three addenda as set forth below, “APPA”), in which Lattice
agreed to provide an advance payment of money to Fujitsu to be used for the
establishment of a new semiconductor wafer fabrication facility, including but
not limited to the construction of the facilities and installation of
fabrication equipments, and Fujitsu agreed to provide to Lattice 300mm Wafers
using certain proprietary technologies; and

 

(ii)

an addendum dated March 22, 2006 (“1st Addendum”) in which Lattice, Fujitsu, and
FMA confirmed that sales and purchases of the 300mm Wafers under Product Supply
Agreements by and between Lattice, Fujitsu, and FMA are also subject to the
Advance Payment terms of the APPA; and

 

(iii)

an addendum dated October 1, 2006 (“2nd Addendum”) in which the parties agreed
that the Advance Payment would be repaid by an offsetting adjustment in the
amount of 200mm Wafers as well as 300mm Wafers purchased by Lattice and sold by
Fujitsu through FMA; and

 

(iv)

an addendum dated September 19, 2007 (“3rd Addendum”) in which the parties
agreed that the Advanced Payment would be repaid by an offsetting adjustment in
the amount of Services as well as 300mm Wafers and 200mm Wafers purchased by
Lattice and sold by Fujitsu through FMA.

WHEREAS, Fujitsu has fully assigned all of its rights and obligations under the
APPA to FML, a wholly-owned subsidiary of Fujitsu incorporated in Japan,
effective March 21, 2008 in accordance with Section 13.4 of the APPA.

WHEREAS, Lattice, FML and FMA wish to modify the APPA to terminate the limited
exclusivity provision of the APPA.

 

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NOW, THEREFORE, in consideration of the mutual promises herein, Lattice, FML and
FMA hereby agree as follows:

1. The Limited Exclusivity provision set forth in Section 5.1.3 is terminated in
its entirety as of the 4th Amendment Effective Date.

2. No Other Changes. Except as expressly stated above, this 4th Addendum does
not otherwise amend the APPA as previously amended, which remains in full force
and effect as amended previously and hereby. Words not expressly defined in this
4th Addendum shall be construed in accordance with the definition in the APPA as
previously amended.

IN WITNESS WHEREOF, the parties have signed this 4th Addendum as of the dates
written below.

 

LATTICE SEMICONDUCTOR CORPORATION     FUJITSU MICROELECTRONICS LIMITED By:   /s/
Tom Kingzett     By:   /s/ Haruyoshi Yagi Name:   Tom Kingzett     Name:  
Haruyoshi Yagi Title:   Corp. VP Product Operations     Title:   Corporate Vice
President Date:   December 18, 2008     Date:   December 16, 2008 FUJITSU
MICROELECTRONICS AMERICA, INC.     By:   /s/ Michael M. Moore       Name:  
Michael M. Moore       Title:   Secretary       Date:   December 17, 2008      

 

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