Three months ago, shares of Silicon Laboratories (NASDAQ:SLAB) fell after the company posted strong third-quarter results but followed with a seemingly conservative forward outlook because of what management described as near-term macroeconomic turbulence. 

With the release of its fourth-quarter results this morning, however, the fabless semiconductor specialist confirmed even that cautious guidance was too optimistic. With the stock down 14% today in response, let's dig deeper to see how Silicon Labs capped 2018, and what investors should be watching in the coming quarters.

Cityscape time lapse with various connected points

Image source: Getty Images.

Silicon Labs results: The raw numbers

Metric

Q4 2018

Q4 2017

Year-Over-Year Growth

Revenue

$215.5 million

$201.0 million

7.2%

GAAP net income

$15.1 million

($4.9 million)

N/A

GAAP diluted earnings per share

$0.35

($0.11)

N/A

Data source: Silicon Labs. 

What happened with Silicon Labs this quarter?

  • Adjusted for items such as stock-based compensation and acquisition costs, Silicon Labs' non-GAAP net income arrived at $40 million, or $0.91 per share. 
  • By comparison, Silicon Labs' guidance provided in October called for higher revenue of $221 million to $227 million, and adjusted earnings per share of $0.91 to $0.97.
  • By segment:
    • Internet of Things (IoT) revenue grew 9% year over year but fell 5% sequentially, in contrast to guidance for continued sequential growth, to $119 million.
    • Infrastructure revenue rose 18% year over year but fell 13% sequentially to $46 million.
    • Broadcast revenue fell 3% both sequentially and year over year to $35 million.
    • Access revenue declined 8% year over year and 7% sequentially, to $15 million.

What management had to say

Silicon Labs CEO Tyson Tuttle stated:

We are proud of our performance in 2018, which was a strong year for Silicon Labs in many dimensions. We completed the successful acquisition of [home automation company] Z-Wave, strengthened our team, and grew our revenue and design wins to record levels. Despite current [macro] volatility, we remain confident about our longer-term ability to outperform the market. We are focused on executing on our product road maps and converting a large pipeline of opportunities into additional wins and share gains. The technologies we are developing are enabling our customers to transform industries and improve lives.

Looking forward

Because of a continued challenging macro environment, Silicon Labs anticipates first-quarter 2019 revenue in the range of $183 million to $193 million, assuming sequential declines in each of its four business segments. That's down from revenue of $205.4 million in the same year-ago period, and -- with the caveat that we don't usually pay close attention to Wall Street's demands -- well below the $219.5 million most analysts were modeling. On the bottom line, that should translate to adjusted earnings per share of between $0.42 and $0.52, down from $0.87 per share in last year's first quarter, and again below the $0.82 per share most investors were expecting.

All things considered, Silicon Labs' long-term story appears to remain firmly intact. But this report was disappointing any way you slice it, and the stock is responding in kind.

Steve Symington has no position in any of the stocks mentioned. The Motley Fool recommends Silicon Laboratories. The Motley Fool has a disclosure policy.