Chipmaker Xilinx ( XLNX) lifted the bottom end of its sales guidance range for the March quarter, sweetening an already-generous forecast. After the close Tuesday, Xilinx said it expects March quarter sales to rise 9% to 10% from the prior quarter, or $398.4 million to $402.1 million. Wall Street analysts are currently modeling for earnings of 25 cents a share on sales of $399 million. Xilinx did not provide EPS guidance. In after-hours trading, Xilinx stock was recently down $1.27, or 3%, to $41.31. In regular trading, the shares closed down 7 cents, or 0.2%, to $42.58. In January, Xilinx shares jumped after the company predicted a sequential revenue increase in the range of 7% to 10%, implying sales of $391.1 million to $402.1 million. Even the low end of the guidance range would have been well above then-prevailing analyst expectations for $361.4 million. Also Tuesday, Xilinx maintained its prior gross margin target of about 63%.