xls convert csv

set_time_limit(0);
ini_set('memory_limit', -1);

include 'PHPExcel/IOFactory.php';

convertXLStoCSV('kamaz.xls','output.csv');

function convertXLStoCSV($infile,$outfile)
{
    $fileType = PHPExcel_IOFactory::identify($infile);
    $objReader = PHPExcel_IOFactory::createReader($fileType);

    $objReader->setReadDataOnly(true);
    $objPHPExcel = $objReader->load($infile);

    $objWriter = PHPExcel_IOFactory::createWriter($objPHPExcel, 'CSV');
    $objWriter->save($outfile);
}