The producer has seen his star rise in the past year as a performer on Robin Thicke's smash hit "Blurred Lines" and Daft Punk's Grammy-winning disco track "Get Lucky." Williams was also nominated for an Oscar for "Happy," the lead song from the "Despicable Me 2" animated film on which he composed the music.
Williams has also carved out a niche as an arbiter of urban style, with such fashions as a tuxedo with shorts at this year's Oscars and a giant brown hat at the Grammys.
"The Voice," which averages about 13.8 million viewers per episode, has outpaced its Fox rival "American Idol" this season by about 3 million viewers per episode.
The show's celebrity panel of judges has been credited with helping it rise in the ratings against "American Idol." It is also considered a top spot within the music industry to promote songs, such as Maroon 5 and Aguilera's "Moves Like Jagger," that became a hit in 2011 after the singers performed it on the show.
The spring panel consists of Shelton and Levine with R&B singer Usher and Colombian pop singer Shakira. Shelton and Levine have served on the panel for every season of the NBC singing competition, while Shakira and Usher stepped in after Green and singer Christina Aguilera opted out of seasons four and six.