Put volume has skyrocketed on ON Semiconductor (ONNN - 7.68) today, as roughly 20,000 puts have crossed the tape so far, reflecting a whopping 1,263 times the equity's intraday volume. The most active option has proved to be the out-of-the-money January 2012 5 strike, where a large block of 16,000 puts was traded at the ask price, suggesting it was purchased. Based on the size of this transaction, it appears to be the work of a large institutional investor. This strike is currently home to peak front-month put open interest of 17,654 contracts.

What's more, the Schaeffer's put/call open interest ratio (SOIR) sits at 0.46, which ranks in the 70th percentile of its annual range. This confirms that short-term options players have been more negatively slanted toward the stock only 30% of the time during the past year.

Meanwhile, short interest on ONNN surged by 53.81% over the past two reporting periods. However, these pessimistic bets account for just 2.76% of the equity's float, indicating that there is still plenty of room on the company's bearish bandwagon. At the stock's average daily trading volume, it would take a day and a half to cover these shorted shares.

From a technical perspective, ONNN has shed close to 23% of its value year-to-date, but has outperformed the broader S&P 500 Index (SPX) by around 4% over the past 20 sessions. A look at the charts shows that the stock is testing its 120-day moving average, which has served as resistance since July.

At last check, ONNN is up about 2% to wink at the $7.68 level.