Segment Information - Narrative (Details) $ in Thousands	12 Months Ended
Jan. 31, 2021 USD ($) segment	Jan. 26, 2020 USD ($)	Jan. 27, 2019 USD ($)
Segment Reporting Information [Line Items]
Net sales	$ 595,117	$ 547,512	$ 627,196
Number of operating segments that aggregate into one reportable segment \| segment	3
Number of reportable segments \| segment	1
Net book value of equipment and machinery	$ 130,934	124,418
Machinery and equipment \| Foundry in China
Segment Reporting Information [Line Items]
Net book value of equipment and machinery	15,000	18,500
Machinery and equipment \| Foundry In Malaysia [Member]
Segment Reporting Information [Line Items]
Net book value of equipment and machinery	$ 4,100	$ 5,500
Net sales revenue
Segment Reporting Information [Line Items]
Minimum concentration risk threshold	10.00%
Concentration risk, percentage	100.00%	100.00%	100.00%
Supplier Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percentage	82.00%	72.00%	68.00%

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Number of Operating Segments that Aggregate into One Reportable Segment

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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