Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Schedule of stock based compensation expense

Stock-based compensation expense included in the Company's consolidated financial statements for the three and six months ended June 30, 2019 and July 1, 2018 was as follows (in thousands):

	Three Months Ended				Six Months Ended
	June 30, 2019		July 1, 2018		June 30, 2019		July 1, 2018
Cost of revenue	$	18	$	35	$	44	$	69
Research and development		532		207		1,187		390
Selling, general and administrative		241		237		511		452
Total costs and expenses	$	791	$	479	$	1,742	$	911

Summary of the activity in the shares available for grant

The following table summarizes the activity in the shares available for grant under the 2019 Plan and 2009 Plan during the six months ended June 30, 2019 (in thousands):

	Shares available for grants
	2019 Plan			2009 Plan
Balance at December 30, 2018		-			6,760
Authorized		5,000			-
RSUs granted		(794	)		(3,355	)
RSUs forfeited or expired		184			762
Options forfeited		15			20
Plan shares expired		-			(4,187	)
Balance at June 30, 2019		4,405			-

Summary of stock options outstanding and stock option activity and the related weighted average exercise price

The following table summarizes stock options outstanding and stock option activity under the 2009 Plan and the 2019 Plan, and the related weighted average exercise price, for the six months ended June 30, 2019:

	Number of Shares			Weighted Average Exercise Price		Weighted Average Remaining Term		Aggregate Intrinsic Value
	(in thousands)					(in years)		(in thousands)
Balance outstanding at December 30, 2018		3,201		$	2.18
Forfeited or expired		(580	)
Exercised		(4	)
Balance outstanding at June 30, 2019		2,617		$	2.29		3.97	$	-
Exercisable at June 30, 2019		2,383		$	2.43		3.65	$	-
Vested and expected to vest at June 30, 2019		2,594		$	2.31		3.94	$	-

Summary of activity for RSUs and PRSUs

A summary of activity for the Company's RSUs for the six months ended June 30, 2019 is as follows:

	RSUs & PRSUs Outstanding
	Number of Shares			Weighted Average Grant Date Fair Value
	(in thousands)
Nonvested at December 30, 2018		2,570		$	1.23
Granted		4,148			0.85
Vested		(926	)		1.08
Forfeited		(401	)		0.96
Nonvested at June 30, 2019		5,391		$	1.04

Summary of the fair value of rights issued pursuant to ESPP

The fair value of rights issued pursuant to the Company's 2009 ESPP was estimated on the commencement date of each offering period using the following weighted average assumptions:

	Three Months Ended						Six Months Ended
	June 30, 2019			July 1, 2018			June 30, 2019			July 1, 2018
Expected term (months)		6.00			6.0			6.00			6.00
Risk-free interest rate		2.40	%		2.09	%		2.40	%		2.09	%
Volatility		53.77	%		44.76	%		53.77	%		44.76	%
Dividend yield		—			—			—			—