CONDENSED UNAUDITED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Apr. 02, 2017	Apr. 03, 2016
Cash flows from operating activities:
Net loss	$ (3,565)	$ (5,093)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	355	312
Stock-based compensation	318	562
Write-down of inventories	104	3
Changes in operating assets and liabilities:
Accounts receivable	(968)	46
Inventories	(948)	(455)
Other assets	183	240
Trade payables	267	(414)
Accrued liabilities	75	348
Deferred revenue	317	0
Other long-term liabilities	(4)	(6)
Net cash used in operating activities	(3,866)	(4,457)
Cash flows from investing activities:
Capital expenditures for property and equipment	(15)	(1,051)
Net cash used in investing activities	(15)	(1,051)
Cash flows from financing activities:
Payment of debt and capital lease obligations	(122)	(75)
Proceeds from line of credit	0	1,000
Proceeds from issuance of common stock	17,069	10,000
Stock issuance costs	(1,242)	(1,200)
Taxes for net issuance of stock awards	(20)	(51)
Net cash provided by financing activities	15,685	9,674
Net increase in cash and cash equivalents	11,804	4,166
Cash and cash equivalents at beginning of period	14,870	19,136
Cash and cash equivalents at end of period	26,674	23,302
Supplemental schedule of non-cash investing and financing activities :
Capital lease obligation to finance capital expenditures	213	414
Purchase of equipment included in accounts payable	$ 15	$ 385