Segment Information - Revenue by Product Line (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2021	Jan. 26, 2020	Jan. 27, 2019
Revenue from External Customer [Line Items]
Net sales	$ 595,117	$ 547,512	$ 627,196
Signal Integrity [Member]
Revenue from External Customer [Line Items]
Net sales	255,640	222,846	276,040
Protection
Revenue from External Customer [Line Items]
Net sales	161,943	157,212	182,068
Wireless and Sensing [Member]
Revenue from External Customer [Line Items]
Net sales	177,534	167,454	190,589
Other: Warrant Shares
Revenue from External Customer [Line Items]
Net sales offset	$ 0	$ 0	$ (21,501)
Net sales revenue
Revenue from External Customer [Line Items]
Concentration risk, percentage	100.00%	100.00%	100.00%
Net sales revenue | Signal Integrity [Member]
Revenue from External Customer [Line Items]
Concentration risk, percentage	43.00%	40.00%	44.00%
Net sales revenue | Protection
Revenue from External Customer [Line Items]
Concentration risk, percentage	27.00%	29.00%	29.00%
Net sales revenue | Wireless and Sensing [Member]
Revenue from External Customer [Line Items]
Concentration risk, percentage	30.00%	31.00%	30.00%
Net sales revenue | Other: Warrant Shares
Revenue from External Customer [Line Items]
Allocated share-based compensation expense as a percentage of net revenue	0.00%	0.00%	(3.00%)