3. Balance Sheet Components

Inventory

Inventory consisted of the following (in thousands):


	December 31,
	2016		2015
Raw materials	$	853	$	361
Work-in-process		3,152		2,205
Finished goods		1,064		1,610
Total inventory	$	5,069	$	4,176

Property and Equipment, Net

Property and equipment, net consisted of the following (in thousands):


	December 31,
	2016		2015
Manufacturing equipment	$	8,983	$	8,256
Computer and network equipment		588		546
Furniture and fixtures		188		184
Software		333		227
Leasehold improvements		13		13
Total property and equipment, gross		10,105		9,226
Less: accumulated depreciation		(8,185)		(7,572)
Total property and equipment, net	$	1,920	$	1,654

Depreciation and amortization expense during the years ended December 31, 2016, 2015 and 2014 was $0.7 million, $1.2 million and $1.3 million, respectively.

Intangible Assets, Net

In 2008, the Company spun-out of Freescale Semiconductor, Inc. (“Freescale,” a wholly-owned subsidiary of NXP Semiconductors N.V.) and acquired certain intellectual property assets and related licenses used in the MRAM business of Freescale. The value assigned to these acquired intangible assets was $910,000. Intangible assets, net consisted of the following (in thousands):


	December 31,
	2016			2015
Acquired technology	$	910	$		910
Less: accumulated amortization		(910)			(778)
Total intangible assets, net	$	—	$		132

Amortization expense was $132,000, $150,000 and $182,000 for the years ended December 31, 2016, 2015 and 2014, respectively.

Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):


	December 31,
	2016			2015
Accrued payroll-related expenses	$	1,045	$	636
Accrued manufacturing-related costs		—		339
Deferred licensing revenue		229		250
Deferred rent		248		220
Accrued sales commissions payable to sales representatives		193		165
Other		96		145
Total accrued liabilities	$	1,811	$	1,755