Balance Sheet Components (Details) - USD ($) $ in Thousands	Sep. 29, 2019	Dec. 30, 2018
Inventories:
Raw materials	$ 191
Work-in-process	2,535	$ 3,120
Finished goods	652	716
Inventories	3,378	3,836
Property and equipment:
Property and equipment, gross	13,002	14,149
Less: Accumulated depreciation and amortization	(11,969)	(12,700)
Property and equipment, net	1,033	1,449
Equipment
Property and equipment:
Property and equipment, gross	10,703	10,607
Software
Property and equipment:
Property and equipment, gross	1,790	2,788
Furniture and fixtures
Property and equipment:
Property and equipment, gross	35	42
Leasehold improvements
Property and equipment:
Property and equipment, gross	$ 474	$ 712

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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