What happened

Shares of Silicon Laboratories (SLAB -8.89%) were up 14.2% as of 1:00 p.m. EDT Wednesday after the fabless semiconductor company announced strong first-quarter 2019 results.

More specifically, Silicon Labs' quarterly revenue declined 8.4% year over year to $188.1 million, right at the midpoint of guidance provided in January for a range of $183 million to $193 million. That translated to adjusted earnings of $25.8 million, or $0.59 per share, down from $0.87 per share a year earlier but well above guidance for a range of $0.42 to $0.52.

Hand holding smartphone with various smart home devices connected.

IMAGE SOURCE: SILICON LABS/ZWAVE.

So what

As usual, the company's Internet of Things products led the way, with the segment's modest 3% year-over-year revenue growth being more than offset by declines from Silicon Labs' other infrastructure, broadcast, and access segments.

But Silicon Labs CEO Tyson Tuttle also stated the company exited last year with "strong design win momentum," noting that first-quarter bookings were "robust" despite macroeconomic headwinds that have held back growth in recent quarters.

"We believe we are well positioned to outperform the market," Tuttle added.

Now what

For the second quarter of 2019, Silicon Labs expects revenue ranging from $202 million to $212 million, assuming sequential growth from each of its four market segments. That should translate to adjusted earnings per share of between $0.70 and $0.80. Even the lower ends of these ranges stood well above Wall Street's consensus estimates for second-quarter earnings of $0.63 per share on revenue of $201.5 million.

Coupled with Silicon Labs' earnings beat to start the year, it's hardly surprising to see the stock rallying in response today.