Note 2 - Significant Accounting Policies (Details Textual)	12 Months Ended
	Jan. 03, 2021 USD ($)	Dec. 29, 2019 USD ($)	Dec. 30, 2018 USD ($)	Jan. 03, 2020 USD ($)	Mar. 31, 2019 USD ($)
Operating Expenses, Denominated in Foreign Currency, Percent	18.00%	19.00%	27.00%
Asset Impairment Charges, Total	$ 44,000	$ 4,000	$ 5,000
Revenue from Contract with Customer, Valuation Allowances And Reserves, Sales Return	30,000	60,000
Operating Lease, Right-of-Use Asset	1,134,000	2,200,000
Goodwill, Ending Balance	185,000	185,000
Deferred Tax Assets, Gross, Total	60,996,000	58,753,000
Deferred Tax Assets, Valuation Allowance, Total	$ 60,486,000	58,140,000		$ 60,000,000
Number of suppliers	1
Sensi ML [Member]
Goodwill, Ending Balance		185,000
Other Noncurrent Assets [Member]
Operating Lease, Right-of-Use Asset	$ 1,800,000				$ 975,000
Other Liabilities [Member]
Operating Lease, Liability, Total	$ 1,900,000				$ 939,000
Licensed Intellectual Property [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	5 years
Restructuring Charges [Member]
Asset Impairment Charges, Total	$ 35,000
Restructuring Charges [Member] | INDIA
Operating Lease, Impairment Loss	93,000
Selling, General and Administrative Expenses [Member]
Marketing and Advertising Expense, Total	$ 76,000	$ 146,000	$ 93,000
Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	1 year
Minimum [Member] | Leasehold Improvements [Member]
Property, Plant and Equipment, Useful Life (Year)	1 year
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	7 years
Finite-Lived Intangible Asset, Useful Life (Year)	5 years
Maximum [Member] | Leasehold Improvements [Member]
Property, Plant and Equipment, Useful Life (Year)	7 years