Note 6 - Segment Information (Tables)

6 Months Ended

1086 Months Ended

Jun. 30, 2013

Jun. 30, 2103

Segment Reporting [Abstract]

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

	Three months ended June 30,						Six months ended June 30,
Customers	2013			2012			2013			2012
A		31	%		30	%		32	%		30	%
B		11	%		*			*			*

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 and Region	2013		2012		2013		2012
China	$	34,743	$	35,091	$	61,522	$	64,184
Taiwan		8,321		7,820		15,840		14,235
Europe		3,327		3,793		7,277		7,983
Korea		2,408		2,600		4,826		4,559
USA		1,839		1,601		3,740		2,713
Japan		1,640		2,355		3,161		4,661
Rest of Asia		5,385		5,295		12,714		10,349
Other		51		52		104		407
Total	$	57,714	$	58,607	$	109,184	$	109,091

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

	Three months ended June 30,				Six months ended June 30,
Product Family	2013		2012		2013		2012
DC to DC converters	$	50,536	$	51,165	$	96,978	$	95,507
Lighting control products		7,178		7,442		12,206		13,584
Total	$	57,714	$	58,607	$	109,184	$	109,091

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

	June 30, 2013		December 31, 2012
China	$	43,553	$	37,071
USA		24,531		23,163
Taiwan		83		90
Japan		43		57
Other		65		55
Total	$	68,275	$	60,436