Note 12 - Segment and Geographic Information (Tables)

6 Months Ended

Sep. 30, 2017

Notes Tables

Revenue from External Customers by Geographic Areas [Table Text Block]

	Three Months Ended				Six Months Ended
	September 30,				September 30,
	2017		2016		2017		2016
	(unaudited)				(unaudited)
United States	$	19,275	$	20,185	$	38,888	$	39,686
Europe and the Middle East:
France		2,010		2,121		3,945		5,571
Germany		10,922		8,960		20,980		17,559
Italy		1,195		915		2,173		1,991
Netherlands		1,420		941		2,816		2,081
United Kingdom		4,687		3,209		8,490		6,836
Other		6,585		5,429		12,439		11,382
Asia Pacific:
China		24,914		21,218		48,733		43,858
Japan		2,146		1,708		4,265		3,426
Malaysia		1,233		1,288		2,057		2,092
Singapore		3,102		3,577		6,121		6,584
South Korea		5,301		4,353		11,114		9,048
Thailand		937		1,040		1,744		1,851
Other		1,828		1,403		3,020		3,150
Rest of the World:
India		818		1,207		1,858		2,107
Other		1,311		1,075		2,583		2,045
Total	$	87,684	$	78,629	$	171,226	$	159,267

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

	Three Months Ended September 30,				Six Months Ended September 30,
	2017		2016		2017		2016
	(unaudited)				(unaudited)
Power semiconductors	$	62,027	$	53,537	$	119,655	$	110,016
Integrated circuits		21,295		20,553		42,467		40,935
Systems and radio frequency power semiconductors		4,362		4,539		9,104		8,316
Total	$	87,684	$	78,629	$	171,226	$	159,267

Schedules of Concentration of Risk, by Risk Factor [Table Text Block]

	Three Months Ended September 30,						Six Months Ended September 30,
	2017			2016			2017			2016
	(unaudited)						(unaudited)
Net Revenues:
Distributor A		15.5	%		13.7	%		15.3	%		13.8	%
Distributor B		10.6	%		10.8	%		10.6	%		10.7	%