Note 2 - Stock Based Compensation (Details) - Summary of Stock-based Compensation Expense (USD $)	3 Months Ended		6 Months Ended
	Sep. 26, 2014	Sep. 27, 2013	Sep. 26, 2014	Sep. 27, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock based compensation expense	$ 16,000	$ 41,000	$ 37,000	$ 70,000
Cost of Sales [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock based compensation expense	2,000	2,000	3,000	4,000
Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock based compensation expense	3,000	7,000	7,000	12,000
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock based compensation expense	10,000	24,000	23,000	39,000
Selling and Marketing Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock based compensation expense	$ 1,000	$ 8,000	$ 4,000	$ 15,000