Exhibit (a)(1)(D)

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT,

NEW YORK CITY TIME, AT THE END OF THE DAY ON MARCH 9, 2015,

UNLESS THE OFFER IS EXTENDED OR EARLIER TERMINATED.

We have been engaged by Cayabyab Merger Company, a Delaware corporation (“Purchaser”) and a wholly owned subsidiary of Lattice Semiconductor Corporation, a Delaware corporation (“Parent”), to act as Information Agent in connection with Purchaser’s offer to purchase all of the outstanding shares of common stock, par value $0.001 per share (the “Shares”), of Silicon Image, Inc., a Delaware corporation (“Silicon Image”), at a purchase price of 7.30 per Share, net to the seller in cash, without interest thereon and less any applicable tax withholding, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated February 9, 2015 (the “Offer to Purchase”), and the related Letter of Transmittal (the “Letter of Transmittal”) and which, together with the Offer to Purchase and other related materials, each as may be amended or supplemented from time to time, we refer to as the “Offer” enclosed herewith. Please furnish copies of the enclosed materials to those of your clients for whom you hold Shares registered in your name or in the name of your nominee.

Certain conditions to the Offer are described in Section 15 of the Offer to Purchase.

For your information and for forwarding to your clients for whom you hold Shares registered in your name or in the name of your nominee, we are enclosing the following documents:

We urge you to contact your clients as promptly as possible. Please note that the Offer and withdrawal rights will expire at 12:00 midnight, New York City time, at the end of the day on March 9, 2015, unless the Offer is extended or earlier terminated.

Any extension, delay, termination or amendment of the Offer will be followed as promptly as practicable by public announcement thereof, and such announcement in the case of an extension will be made no later than 9:00 a.m., New York City time, on the next business day after the previously scheduled expiration date of the Offer.

The Offer is being made pursuant to the Agreement and Plan of Merger, dated as of January 26, 2015 (together with any amendments or supplements thereto, the “Merger Agreement”), by and among Parent, Purchaser and Silicon Image. The Merger Agreement provides that Purchaser will be merged with and into Silicon Image (the “Merger”), with Silicon Image continuing after the Merger as the surviving corporation and a wholly owned subsidiary of Parent.

After careful consideration by the board of directors of Silicon Image, including a review of the terms and conditions of the Merger Agreement, in consultation with Silicon Image’s financial and legal advisors, at a meeting of the board of directors of Silicon Image held on January 26, 2015, the board of directors of Silicon Image unanimously: (i) determined that the Merger Agreement and the transactions contemplated thereby are in the best interests of Silicon Image and Silicon Image’s stockholders, (ii) adopted the Merger Agreement, (iii) approved the transactions contemplated by the Merger Agreement and (iv) recommended that Silicon Image’s stockholders accept the Offer and tender their Shares to the Purchaser pursuant to the Offer.

In order for a stockholder to validly tender Shares pursuant to the Offer, the Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed, together with any required signature guarantees (or, in the case of a book-entry transfer, an Agent’s Message (as defined in the Offer to Purchase) in lieu of the Letter of Transmittal) and any other documents required by the Letter of Transmittal must be received by the Depositary and either (A) the share certificates evidencing tendered Shares must be received by the Depositary or (B) such Shares must be tendered pursuant to the procedure for book-entry transfer described in the Offer to Purchase and a Book-Entry Confirmation (as defined in the Offer to Purchase) must be received by the Depositary (provided in the case of direct registration Shares neither (A) nor (B) will be required), in each case prior to the Expiration Date (as defined in the Offer to Purchase).

If holders of Shares wish to tender their Shares, but it is impracticable for them to deliver their certificates representing tendered Shares or other required documents or to complete the procedures for delivery by book-entry transfer prior to the Expiration Date, a tender may be effected by following the guaranteed delivery procedures specified in the Offer to Purchase and the Letter of Transmittal.

Neither Parent nor Purchaser will pay any fees or commissions to any broker or dealer or any other person (other than to the Depositary and Innisfree M&A Incorporated, as information agent (the “Information Agent”), as described in the Offer to Purchase) in connection with the solicitation of tenders of Shares pursuant to the Offer. Purchaser will, however, upon request, reimburse brokers, dealers, commercial banks and trust companies for customary mailing and handling expenses incurred by them in forwarding materials related to the Offer to their customers. Purchaser will pay all stock transfer taxes applicable to its purchase of Shares pursuant to the Offer, subject to Instruction 6 of the Letter of Transmittal.

Any inquiries you may have with respect to the Offer should be addressed to, and additional copies of the enclosed materials may be obtained from the Information Agent at the address and telephone number set forth on the back cover of the Offer to Purchase.

Nothing contained herein or in the enclosed documents shall render you the agent of Purchaser, the Information Agent or the Depositary or any affiliate of any of them or authorize you or any other person to use any document or make any statement on behalf of any of them in connection with the Offer other than the enclosed documents and the statements contained therein.