Note 13 - Segment and Geographic Information (Tables)

3 Months Ended

Jun. 30, 2017

Notes Tables

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

	Three Months Ended
	June 30,
	2017		2016
	(unaudited)
United States	$	19,613	$	19,501
Europe and the Middle East:
France		1,935		3,450
Germany		10,058		8,599
Italy		978		1,076
Netherlands		1,396		1,140
United Kingdom		3,803		3,627
Other		5,854		5,953
Asia Pacific:
China		23,819		22,640
Japan		2,119		1,718
Singapore		3,019		3,007
South Korea		5,813		4,695
Other		2,823		3,362
Rest of the World:
India		1,040		900
Other		1,272		970
Total	$	83,542	$	80,638

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

	Three Months Ended June 30,
	2017		2016
	(unaudited)
Power semiconductors	$	57,628	$	56,479
Integrated circuits		21,172		20,382
Systems and radio frequency power semiconductors		4,742		3,777
Total	$	83,542	$	80,638

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

	Three Months Ended June 30,
	2017			2016
	(unaudited)
Revenues:
Distributor A		15.2	%		13.8	%
Distributor B		10.7	%		10.6	%