Note 1 - Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 25, 2017

Notes Tables

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

	Three Months Ended
	March 25,			March 26,
	2017			2016
Cost of sales	$	83		$	93
Research and development		316			294
Selling, general and administrative		1,318			1,350
Total share-based compensation		1,717			1,737
Income tax benefit		(75	)		(40	)
Total share-based compensation, net	$	1,642		$	1,697

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

	Three Months Ended
	March 25,		March 26,
	2017		2016
Weighted average common shares		26,978		26,317
Effect of dilutive stock options		1,274		-
		28,252		26,317

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

	Three Months Ended
	March 25,		March 26,
	2017		2016
Customers individually accounting for more than 10% of net sales		one		two
Percentage of net sales		20%		32%