Balance Sheet Components (Details) (USD $) In Thousands, unless otherwise specified	Mar. 30, 2014	Dec. 29, 2013
Inventories:
Raw materials	$ 0	$ 19
Work-in-process	1,620	1,343
Finished goods	3,604	2,774
Inventories	5,224	4,136
Other current assets:
Prepaid expenses	846	845
Other	78	427
Other current assets	924	1,272
Accrued liabilities:
Employee related accruals	1,640	2,821
Other	1,004	698
Accrued liabilities	$ 2,644	$ 3,519