Note 1 - Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 27, 2015

Notes Tables

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	Three Months Ended						Six Months Ended
	June 27,			June 28,			June 27,			June 28,
	2015			2014			2015			2014
Cost of sales	$	198		$	190		$	313		$	265
Research and development		254			422			585			911
Selling, general and administrative		1,294			1,001			2,546			1,872
Total share-based compensation		1,746			1,613			3,444			3,048
Income tax benefit		(67	)		(56	)		(111	)		(97	)
Total share-based compensation, net	$	1,679		$	1,557		$	3,333		$	2,951

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	Three Months Ended				Six Months Ended
	June 27,		June 28,		June 27,		June 28,
	2015		2014		2015		2014
Weighted average common shares		26,059		25,324		25,905		25,223
Effect of dilutive stock options		663		473		715		-
		26,722		25,797		26,620		25,223

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

	Three Months Ended				Six Months Ended
	June 27,		June 28,		June 27,		June 28,
	2015		2014		2015		2014
Customers individually accounting for more than 10% of net sales		two		three		two		three
Percentage of net sales		28%		39%		28%		39%