Volterra Semiconductor (Nasdaq: VLTR) reported earnings on July 22. Here are the numbers you need to know.

The 10-second takeaway
 For the quarter ended June 30 (Q2), Volterra Semiconductor missed estimates on revenues and missed estimates on earnings per share.

Compared to the prior-year quarter, revenue dropped significantly. Non-GAAP earnings per share contracted significantly. GAAP earnings per share shrank significantly.

Gross margins grew, operating margins shrank, net margins contracted.

Revenue details
 Volterra Semiconductor chalked up revenue of $34.4 million. The 12 analysts polled by S&P Capital IQ wanted to see net sales of $35.6 million on the same basis. GAAP reported sales were 21% lower than the prior-year quarter's $43.6 million.

Source: S&P Capital IQ. Quarterly periods. Dollar amounts in millions. Non-GAAP figures may vary to maintain comparability with estimates.

EPS details
 EPS came in at $0.13. The 11 earnings estimates compiled by S&P Capital IQ predicted $0.16 per share. Non-GAAP EPS of $0.13 for Q2 were 59% lower than the prior-year quarter's $0.32 per share. GAAP EPS of $0.03 for Q2 were 86% lower than the prior-year quarter's $0.22 per share.

Source: S&P Capital IQ. Quarterly periods. Non-GAAP figures may vary to maintain comparability with estimates.

Margin details
 For the quarter, gross margin was 58.1%, 10 basis points better than the prior-year quarter. Operating margin was 5.9%, much worse than the prior-year quarter. Net margin was 2.2%, much worse than the prior-year quarter. (Margins calculated in GAAP terms.)

Looking ahead
 Next quarter's average estimate for revenue is $37.2 million. On the bottom line, the average EPS estimate is $0.20.

Next year's average estimate for revenue is $150.6 million. The average EPS estimate is $0.82.

Investor sentiment
 The stock has a four-star rating (out of five) at Motley Fool CAPS, with 112 members out of 126 rating the stock outperform, and 14 members rating it underperform. Among 40 CAPS All-Star picks (recommendations by the highest-ranked CAPS members), 36 give Volterra Semiconductor a green thumbs-up, and four give it a red thumbs-down.

Of Wall Street recommendations tracked by S&P Capital IQ, the average opinion on Volterra Semiconductor is outperform, with an average price target of $16.85.

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