In addition, the company said President and CEO Daniel Artusi resigned to pursue other interests.
Silicon Labs' shares were off in after-hours trading, falling to $29.93 after closing the regular session at $30.80.
The communications-chip maker said after the bell Monday that first-quarter net income fell to $17.4 million, or 31 cents a share, from $19.9 million, or 36 cents a share a year earlier.
Revenue fell to $104.8 million from $113.6 million.
A Thomson First Call survey of analysts had expected, on average, the company to earn 26 cents a share on revenue of $103.1 million.
During the quarter, the broad-based mixed-signal business posted stronger than expected growth, and mobile handset revenue rebounded, the company said. Mobile handset revenue increased by 9%.
The company expects revenue of $105 million to $108 million in the second quarter. The First Call consensus is $108.5 million.
Nav Sooch, chairman of the board, was named as interim chief executive officer.