Image source: Littelfuse. Littelfuse (NASDAQ: LFUS), a manufacturer of circuit protection products, reported its second-quarter results before the market opened on Aug. 4. The acquisition of the PolySwitch business boosted revenue, but the company posted solid organic growth as well, with the automotive segment reporting a double-digit increase in sales. Here's what investors need to know about Littelfuse's results. Littelfuse: The raw numbers Metric Q2 2016 Q2 2015 Growth (YOY) Revenue $271.9 million $222.0 million 22% Net income $27.2 million $28.7 million (5.3%) GAAP EPS $1.20 $1.26 (4.8%) Adjusted EPS $1.44 $1.33 8.3% Data source: Littelfuse Q2 earnings report.. What happened with Littelfuse this quarter? The acquisition of the PolySwitch business was responsible for most of Littelfuse's growth, but the company still grew sales on an adjusted basis. Excluding PolySwitch, revenue increased by 6% year over year. Electronics sales rose 25%, with a 2% increase excluding PolySwitch. Higher sensor and fuse sales were counteracted by lower semiconductor sales. Automotive sales increased 30%, with a 15% increase excluding PolySwitch. Asia and Europe in particular were areas of strength. Industrial sales slumped 7%, driven by weakness in the mining, oil, and gas end markets. Operating income rose 14% and 30% in the electronics and automotive segments, respectively. The industrial segment suffered a 57% decline. Littelfuse also provided guidance for the third quarter. Revenue is expected to be in the range of $262 million to $272 million, with $40 million coming from PolySwitch sales. Revenue will grow by 24% at the midpoint, or by 5% excluding PolySwitch. Adjusted EPS is expected to be in the range of $1.36 to $1.50. This compares to $1.43 during the third quarter of 2015. What management had to say Littelfuse CEO Gordon Hunter praised his teams for performing well in a difficult environment: Our teams have continued to execute well within an uncertain macro environment. Operating margins improved in both our electronics and automotive segments, while our teams also focused on integrating the PolySwitch business. Our industrial segment continued to face end market weakness, and we've taken recent actions to reduce our cost structure across the segment. Despite these challenges, we remain on track for meaningful margin expansion this year as we continue to execute on our footprint consolidations and portfolio initiatives. However, Hunter expects headwinds to continue: Despite the headwinds in some of our markets, our business trends remain solid. We've had a strong start to the year with positive momentum across our electronics and automotive segments, and are pleased with the performance of the PolySwitch business to date. However, end market challenges in our industrial segment have impacted profitability, and are expected to continue through this year. Looking forward Littelfuse produced a strong quarter despite weakness in its industrial business. GAAP earnings declined mainly due to costs associated with the acquisition of the PolySwitch business. The company's adjusted profit, which backs out only one-time expenses, is a good representation of Littelfuse's true earnings power. The company expects solid growth to continue in the third quarter, even excluding the PolySwitch business. Littelfuse's guidance calls for roughly flat adjusted EPS, with the PolySwitch business not yet contributing much to earnings. The company expects to achieve $10 million of cost synergies annually starting in 2017, although Littelfuse didn't give an update on the integration process. A secret billion-dollar stock opportunity The world's biggest tech company forgot to show you something, but a few Wall Street analysts and the Fool didn't miss a beat: There's a small company that's powering their brand-new gadgets and the coming revolution in technology. And we think its stock price has nearly unlimited room to run for early in-the-know investors! To be one of them, just click here.Timothy Green has no position in any stocks mentioned. The Motley Fool recommends Littelfuse. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.