Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 25, 2021	Sep. 26, 2020	Sep. 25, 2021	Sep. 26, 2020
Net sales		$ 225,063	$ 150,647	$ 695,354	$ 433,652
Cost and expenses:
Cost of sales (1)	[1]	129,358	87,147	392,787	253,111
Research and development		22,792	20,497	69,367	63,389
Selling, general and administrative		30,377	31,336	95,835	95,664
Amortization of purchased intangible assets		8,879	9,783	27,168	28,848
Restructuring charges		31	412	1,988	1,400
Impairment charges		0	7,300	0	11,249
Gain on sale of facilities		0	(4,468)	0	(4,495)
Gain on sale of PCB Test business (2)	[2]	(90)	0	(75,754)	0
Costs and Expenses, Total		191,347	152,007	511,391	449,166
Income (loss) from operations		33,716	(1,360)	183,963	(15,514)
Other (expense) income:
Interest expense		(966)	(3,021)	(5,372)	(10,904)
Interest income		53	42	197	210
Foreign transaction loss		(28)	(1,484)	(315)	(2,528)
Gain (loss) on extinguishment of debt		(1,650)	293	(3,411)	293
Income (loss) from continuing operations before taxes		31,125	(5,530)	175,062	(28,443)
Income tax provision		7,392	1,116	28,626	261
Income (loss) from continuing operations		23,733	(6,646)	146,436	(28,704)
Income from discontinued operations		0	0	0	42
Net income (loss)		$ 23,733	$ (6,646)	$ 146,436	$ (28,662)
Basic:
Income (loss) from continuing operations (in dollars per share)		$ 0.49	$ (0.16)	$ 3.12	$ (0.69)
Income from discontinued operations (in dollars per share)		0	0	0	0.00
Net income (loss) (in dollars per share)		0.49	(0.16)	3.12	(0.69)
Diluted:
Income (loss) from continuing operations (in dollars per share)		0.48	(0.16)	3.04	(0.69)
Income from discontinued operations (in dollars per share)		0	0	0	0.00
Net income (loss) (in dollars per share)		$ 0.48	$ (0.16)	$ 3.04	$ (0.69)
Weighted average shares used in computing income (loss) per share:
Basic (in shares)		48,666	41,947	46,992	41,764
Diluted (in shares)		49,457	41,947	48,137	41,764
Cash dividend, per share (in dollars per share)		$ 0	$ 0	$ 0	$ 0.06

[1] Excludes amortization of $6,988 and $7,447 for the three months ended September 25, 2021 and September 26, 2020, respectively, and $21,133 and $21,969 for the nine months ended September 25, 2021 and September 26, 2020, respectively.

[2] On June 24, 2021 we completed the divestment of our PCB Test business. The divestment of this business did not qualify for presentation as discontinued operations and the results of the PCB Test business are included in continuing operations for all periods presented. See Note 12, “Business Divestitures and Discontinued Operations” for additional information on this transaction and financial statement presentation.