Note 6 - Segment and Geographic Information (Tables)

6 Months Ended

Jun. 30, 2017

Notes Tables

Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]

	Three Months Ended June 30,						Six Months Ended June 30,
Customer	2017			2016			2017			2016
Distributor A		17	%		24	%		17	%		22	%

Schedule of Accounts Receivable by Major Customers by Reporting Segments [Table Text Block]

	June 30,			December 31,
Customer	2017			2016
Distributor A		20	%		19	%
Distributor B		14	%		17	%

Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area [Table Text Block]

	Three Months Ended June 30,				Six Months Ended June 30,
Country or Region	2017		2016		2017		2016
China	$	62,325	$	60,928	$	118,409	$	113,316
Taiwan		17,286		10,160		32,161		19,015
Europe		9,593		7,054		17,501		14,039
Korea		8,154		7,024		16,315		14,117
Southeast Asia		6,925		3,501		13,297		7,840
Japan		4,945		3,037		9,771		5,687
United States		2,888		2,303		4,930		4,449
Other		82		72		176		128
Total	$	112,198	$	94,079	$	212,560	$	178,591

Revenue from External Customers by Products and Services [Table Text Block]

	Three Months Ended June 30,				Six Months Ended June 30,
Product Family	2017		2016		2017		2016
DC to DC	$	102,187	$	84,221	$	193,611	$	161,339
Lighting Control		10,011		9,858		18,949		17,252
Total	$	112,198	$	94,079	$	212,560	$	178,591

Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country [Table Text Block]

	June 30,		December 31,
Country	2017		2016
United States	$	59,749	$	50,242
China		46,598		45,728
Taiwan		16,940		8,919
Bermuda		8,548		9,573
Other		424		571
Total	$	132,259	$	115,033