Downers Grove-based Dover Corp. has reached an $855 million deal to acquire NXP Semiconductors NV’s Sound Solutions business, which makes speaker and receiver components for the mobile handset market.

Dover, an industrial conglomerate, makes products that range from the microphones in Apple Inc.’s iPhone to the diamond inserts used in drill bits for oil and gas exploration.

The NXP deal, set to close in the first quarter, also includes a strategic relationship in which NXP will become the exclusive provider of certain mixed-signal semiconductors to Dover’s Knowles Electronics business, which makes components for hearing aid and other acoustic products.

About 1,000 Sound Solutions employees in Austria and China will join Knowles. Sound Solutions is based in Vienna, Austria.

NXP said the deal would strengthen its balance sheet and allow it to focus on its mixed-signal business.

Dover in October reported that its third-quarter profit more than doubled as revenue improved and orders increased across the board. NXP has also seen rebounding results this year after the woes seen in 2009 by the chip industry.