Shares of PowerDsine ( PDSN) were among technology's losers Thursday, sliding 25% after the chip designer cut its fourth-quarter sales guidance and warned that it would post a loss for the period. The Israeli company now sees sales of $7 million to $7.5 million, which will translate into a fourth-quarter loss of 3 cents to 5 cents a share. Previously, the company said that it would post sales of $11.2 million to $11.4 million. The company blamed the shortfall on weak sales of its Midspan product. "We are disappointed with our PoE Midspan product sales during the fourth quarter and the significant decline in customer orders," the company said. Analysts polled by Thomson First Call project fourth-quarter earnings of 7 cents a share on sales of $11.3 million. Shares were trading down $2.27 to $6.78. On Semiconductor ( ONNN) traded actively after the chipmaker raised its fourth-quarter sales guidance and announced a convertible note sale. The company now sees sequential sales growth of 4% to 6%, up from its previous view of 2% to 3%. During the third quarter, the company posted sales of $313.6 million, which would put the new sales guidance at $326 million to $332 million. Analysts project fourth-quarter sales of $321.3 million. The company said that its consumer-driven end markets continued to grow "robustly" in the fourth quarter. Separately, On Semiconductor said that it plans to sell $95 million of convertible senior subordinated notes in a private placement. The company plans to use proceeds from the sale to repay its outstanding 10% junior subordinated note due 2011. Any proceeds that are not used to repay the junior note, the company said, will be used for general corporate needs. Shares were recently trading down 28 cents, or 5%, to $5.72. Shares of WPCS International ( WPCS) climbed 15% after the company posted big year-over-year gains in second-quarter earnings and sales. The company, which provides wireless engineering services, said earnings rose to $785,000, or 20 cents a share, from $31,000, or 2 cents a share, a year earlier. Sales grew to $14.3 million from $10.3 million. The company said that its strong second-quarter results keep it on track to post earnings of 58 cents a share for the entire year. Shares were trading up $1.17 to $8.82.