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What: Shares of ON Semiconductor (UNKNOWN:ONNN.DL) have plunged today by as much as 11% after the company reported earnings.

So what: Second-quarter revenue totaled $688.3 million, which was moderately below the $696 million estimate. Non-GAAP earnings per share of $0.13 was exactly what investors thought was coming. CEO Keith Jackson said that some markets were weak, but the company has confidence in its current design wins.

Now what: Guidance left a little to be desired, though, with third-quarter revenue expected in the range of $700 million to $730 million. Average selling prices are expected to decline sequentially, and gross margin should be 33.8% to 35.8%. The Street had been modeling for over $737 million in revenue.

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