What happened

Shares of Cirrus Logic (NASDAQ:CRUS) jumped on Thursday after the audio chip developer's fiscal second-quarter results beat analyst estimates by a wide margin. The stock was up 14.6% at 12:15 p.m. EDT.

So what

Cirrus reported second-quarter revenue of $388.9 million, up 6.2% year over year and $68.5 million higher than the average analyst estimate. Growth was driven by stronger-than-expected demand for certain components. Apple, Cirrus' largest customer, accounted for 81% of total revenue.

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Non-GAAP (adjusted) earnings per share came in at $1.55, up from $1.08 in the prior-year period and $0.61 higher than analysts were expecting. Revenue growth, a 3-percentage-point increase in gross margin, and a reduction in operating costs drove the substantial earnings growth.

"The company continues to experience increased demand for products that solve complex analog and digital signal-processing challenges," said Cirrus CEO Jason Rhode in prepared remarks included in the earnings release.

Now what

For the third fiscal quarter, Cirrus expects to produce revenue between $325 million and $365 million. That guidance range straddles the average analyst estimate of $338.9 million.

The global smartphone market grew slightly in the third calendar quarter, according to Strategy Analytics, the first period of growth in two years. That's good news for Cirrus, especially given its heavy dependence on Apple's iPhone.

Including Thursday's gains, Cirrus stock is now up more than 100% year to date.