CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended									12 Months Ended
	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 28, 2013	Sep. 28, 2013	Jun. 29, 2013		Mar. 30, 2013	Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Revenues	$ 71,285	$ 73,934	$ 67,352	$ 55,959	$ 48,546	$ 67,634	$ 62,733	[1]	$ 52,620	$ 268,530	$ 231,533	$ 178,535
Cost of revenues	50,337	49,792	47,328	43,634	44,288	55,088	46,328	[1]	43,545	191,091	189,249	153,204
Gross profit	20,948	24,142	20,024	12,325	4,258	12,546	16,405		9,075	77,439	42,284	25,331
Operating expenses:
Research and development	10,706	11,198	11,074	9,747	9,994	10,301	10,915	[1]	10,929	42,725	42,139	40,130
Selling, general and administrative	12,631	13,309	13,191	12,254	12,160	12,952	13,487	[1]	14,618	51,385	53,217	49,231
Restructuring charges, net	584	28	59	1,997	443	143	92	[1]	3,980	2,668	4,658	2,917
Restructuring charges, net										2,668
Loss on sale of subsidiary	0	0	0	0	0	0	300		0	0	300	0
Impairment of long-lived assets	390	86	0	743	567	15	121	[1]	58	1,219	761	421
Gain on settlement of litigation										0	0	(3,250)
Total operating expenses	24,311	24,621	24,324	24,741	23,164	23,411	24,915		29,585	97,997	101,075	89,449
Operating loss	(3,363)	(479)	(4,300)	(12,416)	(18,906)	(10,865)	(8,510)		(20,510)	(20,558)	(58,791)	(64,118)
Interest income, net	69	75	79	79	88	95	96	[1]	107	302	386	691
Other income, net	155	228	(156)	(66)	82	(91)	209	[1]	423	161	623	1,461
Loss before income taxes	(3,139)	(176)	(4,377)	(12,403)	(18,736)	(10,861)	(8,205)		(19,980)	(20,095)	(57,782)	(61,966)
Benefit from income taxes	(1,268)	101	(51)	308	53	(147)	202	[1]	(207)	(910)	(99)	(26,420)
Net loss	$ (1,871)	$ (277)	$ (4,326)	$ (12,711)	$ (18,789)	$ (10,714)	$ (8,407)		$ (19,773)	$ (19,185)	$ (57,683)	$ (35,546)
Net loss per share:
Basic and diluted (usd per share)	$ (0.03)	$ 0.00	$ (0.08)	$ (0.23)	$ (0.34)	$ (0.20)	$ (0.16)		$ (0.37)	$ (0.34)	$ (1.06)	$ (0.70)
Weighted-average number of shares used in per share calculations:
Basic and diluted (shares)	56,472	56,297	55,812	55,050	54,608	54,437	54,105		53,664	55,908	54,204	50,551

[1] In the second quarter of fiscal 2013, we recorded a $0.3 million loss on the sale of our subsidiary, TMMC. See Note 7, Fair Value, to the Notes to Consolidated Financial Statements for further details relating to the terms of the sale.