Balance Sheets Components

Marketable Securities

Marketable securities at October 1, 2017 consisted of the following:



	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(in thousands)
Corporate debt securities	$	81,438	$	19	$	(36	)	$	81,421
Government debt securities	6,604		—		(3		)	6,601
	$	88,042	$	19	$	(39	)	$	88,022

The contractual maturities of marketable securities as of October 1, 2017 were as follows:



	Amortized Cost		Fair Value
	(in thousands)
Due in one year or less	$	40,663	$	40,652
Due after one year to five years	47,379		47,370
	$	88,042	$	88,022

There were no marketable securities as of January 1, 2017.

Property and Equipment, Net

Property and equipment, net consisted of the following:



	October 1, 2017			January 1, 2017
	(in thousands)
Computer and lab equipment	$	13,342		$	9,748
Computer software	795			625
Furniture and fixtures	203			136
Leasehold improvements	342			218
Sub-total	14,682			10,727
Accumulated depreciation and amortization	(7,550		)	(5,985		)
Net long-lived assets	$	7,132		$	4,742
Construction-in-progress	4,083			—
Total	$	11,215		$	4,742

Depreciation and amortization expense related to property and equipment was $0.5 million and $0.3 million, respectively, for the three months ended October 1, 2017 and September 25, 2016, and $1.6 million and $0.9 million, respectively, for the nine months ended October 1, 2017 and September 25, 2016.

Inventory

Inventory consisted of the following:



	October 1, 2017		January 1, 2017
	(in thousands)
Raw materials	$	17,478	$	9,067
Work in progress	2,626		1,128
Finished goods	3,596		5,625
	$	23,700	$	15,820

Accrued Liabilities and Other Current Liabilities

Accrued liabilities and other current liabilities consisted of the following:



	October 1, 2017		January 1, 2017
	(in thousands)
Accrued payroll and related benefits	$	3,421	$	2,842
Accrued customer rebates	12,452		3,026
Accrual for inventory purchases	1,913		1,353
Accrued expenses	6,763		2,952
ESPP employee contributions	1,719		665
Other	1,673		963
	$	27,941	$	11,801