Note 12 - Segment and Geographical Information - Net Revenue to Each Significant Country Based on the Ship-to Location (Details) - USD ($)
$ in Thousands
3 Months Ended
Apr. 29, 2017
Apr. 30, 2016
Sales revenue, net $ 39,564 $ 53,775
CHINA    
Sales revenue, net 21,790 27,457
TAIWAN, PROVINCE OF CHINA    
Sales revenue, net 6,951 13,964
UNITED STATES    
Sales revenue, net 5,520 6,589
KOREA, REPUBLIC OF    
Sales revenue, net 1,675 1,511
Rest of the World [Member]    
Sales revenue, net $ 3,628 $ 4,254