Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017		Oct. 01, 2016
Operating activities:
Net loss	$ (7,712)		$ (898)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Gain on sale of intellectual property	(175)
Depreciation and amortization	660		461
Change in fair value of earn-out liability	122		86
Stock-based compensation	1,357		1,270
Provision for doubtful accounts	(4)		66
Changes in operating assets and liabilities:
Accounts receivable	2,639		1,290
Inventories	974		(1,572)
Prepaid expenses and other current assets	(221)		(839)
Other long-term assets	32		77
Accounts payable	(130)		249
Accrued compensation	(8)		2
Accrued expenses	(347)		16
Accrued warranty	79		(33)
Deferred revenue	20		(6)
Other long-term liabilities	80		26
Net cash (used in) provided by operating activities	(2,634)		195
Investing activities:
Acquisition of property and equipment	(542)		(792)
Proceeds from sale of intellectual property	175
Payment on earn-out liability	(292)		(313)
Net cash used in investing activities	(659)		(1,105)
Financing activities:
Proceeds from issuance of common stock, net of issuance costs	2,263
Proceeds from stock option exercises	328		650
Taxes paid related to net share settlements of equity awards	(294)		(99)
Repurchase of common stock			(59)
Net cash provided by financing activities	2,297		492
Net decrease in cash and cash equivalents	(996)		(418)
Cash and cash equivalents, beginning of period	23,747	[1]	9,995
Cash and cash equivalents, end of period	22,751		9,577
Cash paid during the period for:
Income taxes	$ 19		$ 37

[1] Derived from the audited consolidated financial statements included in the Annual Report on Form 10-K filed with the SEC for the year ended December 31, 2016.