Texas Instruments ( TXN) slightly improved on its dismal fourth-quarter forecast, although it still expects a decent-sized sequential slide in revenue. After the bell Monday, the company raised its previous sales and earnings guidance for the quarter ending in December. Shares popped 88 cents, or 4.5%, to $20.65 in after-hours trading. TI said it now expects overall revenue to be down about 7% sequentially, instead of the 10% slide it had predicted in October. The decrease mostly reflects a seasonal drop in calculator shipments. Earnings will total about a penny as calculated by generally accepted accounting principles, a little better than the break-even point management had outlined. Still, TI gave itself wiggle room of a few cents either way, leaving open the possibility that the quarter will end in the red. Pro forma profit is expected to be 3 cents, which remains well below the October quarter's 9 cents per share. Within the semiconductor division, revenue is now expected to decline about 2% sequentially, instead of the 5% previously forecast. In a statement, CFO Bill Aylesworth said the improved expectations for the quarter are due to stronger demand for wireless and high-performance analog products. Leading up to TI's update today, analysts had been gearing for sales of $2 billion, reflecting an 8.8% sequential decrease in revenues, according to Thomson Financial/First Call. They had expected pro forma earnings to reach 2 cents.