SAN FRANCISCO - Memory chip maker SanDisk ( SNDK) sailed past analysts' expectations for the fourth quarter despite a challenging business environment for many semiconductor companies. SanDisk reported net income of $106 million, or 45 cents a share in the quarter, compared with a net loss of $35 million, or 17 cents a share, in the fourth quarter a year ago that included a write-off of acquired technology. Excluding the impact of acquisition and other charges, net income increased to $162 million, or 69 cents a share, compared with $192 million, or 87 cents a share, the year before. Revenue rose 7% to $1.25 billion from $1.16 billion a year ago. Analysts polled by Thomson Financial were expecting earnings of 64 cents a share on revenue of $1.27 billion. Shares of SanDisk closed up 27 cents, or 1%, to $25.89. "We continued to see strong growth in our mobile business where we sold 51 million units and our diversified and differentiated product portfolio delivered sequential growth in product gross margin," Eli Harari, chairman and CEO of SanDisk said in a statement. "Despite current uncertainties in the worldwide economy and a challenging industry pricing environment in the first quarter, we expect to grow our top and bottom line in 2008, driven by continuing strength in our mobile markets, our expanding international retail footprint and our competitive cost structure," Harari said. Product revenue in the fourth quarter increased 4% from a year ago to $1.12 billion and was up 22% from the last quarter. License and royalty revenue soared 51% to $128 million from the year before. Excluding charges, the product gross margin in the quarter was 29.7% in the quarter compared to 32.3% a year ago and 26.4% the previous quarter.