Note 13 - Net Revenue to Each Significant Country Based on the Ship-to Location (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2015	Nov. 01, 2014	Oct. 31, 2015	Nov. 01, 2014
CHINA
Sales revenue, net	$ 26,556	$ 20,341	$ 69,861	$ 51,159
TAIWAN, PROVINCE OF CHINA
Sales revenue, net	15,355	7,615	39,520	18,605
UNITED STATES
Sales revenue, net	11,300	4,007	33,395	13,416
Thailand [Member]
Sales revenue, net	1,428	14,191	11,021	28,472
Rest of the World [Member]
Sales revenue, net	6,942	7,630	22,003	21,815
Sales revenue, net	$ 61,581	$ 53,784	$ 175,800	$ 133,467