Condensed Unaudited Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 28, 2015	Jun. 29, 2014
Cash flows from operating activities:
Net loss	$ (7,916)	$ (5,007)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	727	727
Stock-based compensation	988	1,298
Write-down of inventories	13	99
Gains on disposal of equipment	0	(2)
Changes in operating assets and liabilities:
Accounts receivable	(45)	1,285
Inventories	1,938	(3,614)
Other assets	409	234
Trade payables	(533)	(1,028)
Accrued liabilities and deferred revenue	617	(583)
Other long-term liabilities	79	(59)
Net cash used in operating activities	(3,723)	(6,650)
Cash flows from investing activities:
Capital expenditures for property and equipment	(163)	(522)
Proceeds from sale of fixed assets	0	2
Net cash used in investing activities	(163)	(520)
Cash flows from financing activities:
Payment of debt and capital lease obligations	(158)	(114)
Stock issued under share-based compensation, net	409	4,208
Net cash provided by financing activities	251	4,094
Net (decrease) in cash and cash equivalents	(3,635)	(3,076)
Cash and cash equivalents at beginning of period	30,050	37,406
Cash and cash equivalents at end of period	26,415	34,330
Supplemental schedule of non-cash investing and financing activities :
Capital lease obligation to finance capital expenditures	258	435
Purchase of equipment included in accounts payable	$ 36	$ 306