Organization and Basis of Presentation	12 Months Ended
Jan. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation Semtech Corporation (together with its subsidiaries, the “Company” or “Semtech”) is a global supplier of analog and mixed-signal semiconductor products. The end-customers for the Company’s products are primarily original equipment manufacturers (“OEM’s”) that produce and sell electronics. The Company designs, develops, and markets a wide range of products for commercial applications, the majority of which are sold into the enterprise computing, communications, high-end consumer and industrial end-markets. Enterprise Computing: datacenters, passive optical networks, desktops, notebooks, servers, graphic boards, monitors, printers and other computer peripherals. Communications: base stations, optical networks, carrier networks, switches and routers, cable modems, wireless LAN and other communication infrastructure equipment. High-End Consumer: handheld products, smartphones, wireless charging, set-top boxes, digital televisions, tablets, digital video recorders and other consumer equipment. Industrial: video broadcast equipment, automated meter reading, Internet of Things ("IoT"), smart grid, wireless charging, military and aerospace, medical, security systems, automotive, industrial and home automation, video security and surveillance and other industrial equipment. Fiscal Year The Company reports results on the basis of 52 and 53 week periods and ends its fiscal year on the last Sunday in January. The fiscal year ended January 31, 2016 consisted of 53 weeks. The fiscal years January 25, 2015 and January 26, 2014 each consisted of 52 weeks. Principles of Consolidation The accompanying consolidated financial statements include the accounts of Semtech Corporation and its wholly-owned subsidiaries. All inter-company transactions and accounts have been eliminated. On March 4, 2015, the Company completed the acquisition of Triune Systems, L.L.C. (“Triune”). On January 13, 2015, the Company completed the acquisition of EnVerv, Inc. (“EnVerv”). The consolidated financial statements include the results of operations of Triune and EnVerv commencing as of the acquisition date. Segment Information The Company's Chief Executive Officer (“CEO”) has been identified as the Chief Operating Decision Maker (“CODM”) as defined by guidance regarding segment disclosures (see Note 16 for further discussion). In fiscal year 2015, the Company completed the reassessment of its operations in light of its restructuring efforts (see Note 17 for further discussion) and recent strategic business decisions. Based on this reassessment, the Company has identified five operating segments in total. Four of the five operating segments aggregate into one reportable segment, the Semiconductor Products Group. The remaining operating segment, the Systems Innovation Group (shown as “All others”), could not be aggregated with the other operating segments and did not meet the criteria for a separate reportable segment as defined by the guidance regarding segment disclosure. As a result, the financial activity associated with the Systems Innovation Group is reported separately from the Company's Semiconductor Products Group. This separate reporting is included in the “All others” category. Prior to fiscal year 2015, the Company included “All others” as part of the Company’s one reportable segment. The historical activity of the reportable segment and “All others” has been recast for consistent presentation for all periods presented. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Reclassification Certain prior period footnote amounts have been re-cast to reflect the effect of the changes to the Company's identified operating segments. See Note 16.

Organization and Basis of Presentation

Semtech Corporation (together with its subsidiaries, the “Company” or “Semtech”) is a global supplier of analog and mixed-signal semiconductor products. The end-customers for the Company’s products are primarily original equipment manufacturers (“OEM’s”) that produce and sell electronics.

The Company designs, develops, and markets a wide range of products for commercial applications, the majority of which are sold into the enterprise computing, communications, high-end consumer and industrial end-markets.

Enterprise Computing: datacenters, passive optical networks, desktops, notebooks, servers, graphic boards, monitors, printers and other computer peripherals.

Communications: base stations, optical networks, carrier networks, switches and routers, cable modems, wireless LAN and other communication infrastructure equipment.

High-End Consumer: handheld products, smartphones, wireless charging, set-top boxes, digital televisions, tablets, digital video recorders and other consumer equipment.

Industrial: video broadcast equipment, automated meter reading, Internet of Things ("IoT"), smart grid, wireless charging, military and aerospace, medical, security systems, automotive, industrial and home automation, video security and surveillance and other industrial equipment.

Fiscal Year

The Company reports results on the basis of 52 and 53 week periods and ends its fiscal year on the last Sunday in January. The fiscal year ended January 31, 2016 consisted of 53 weeks. The fiscal years January 25, 2015 and January 26, 2014 each consisted of 52 weeks.

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of Semtech Corporation and its wholly-owned subsidiaries. All inter-company transactions and accounts have been eliminated.

On March 4, 2015, the Company completed the acquisition of Triune Systems, L.L.C. (“Triune”). On January 13, 2015, the Company completed the acquisition of EnVerv, Inc. (“EnVerv”). The consolidated financial statements include the results of operations of Triune and EnVerv commencing as of the acquisition date.

Segment Information

The Company's Chief Executive Officer (“CEO”) has been identified as the Chief Operating Decision Maker (“CODM”) as defined by guidance regarding segment disclosures (see Note 16 for further discussion). In fiscal year 2015, the Company completed the reassessment of its operations in light of its restructuring efforts (see Note 17 for further discussion) and recent strategic business decisions. Based on this reassessment, the Company has identified five operating segments in total. Four of the five operating segments aggregate into one reportable segment, the Semiconductor Products Group. The remaining operating segment, the Systems Innovation Group (shown as “All others”), could not be aggregated with the other operating segments and did not meet the criteria for a separate reportable segment as defined by the guidance regarding segment disclosure. As a result, the financial activity associated with the Systems Innovation Group is reported separately from the Company's Semiconductor Products Group. This separate reporting is included in the “All others” category. Prior to fiscal year 2015, the Company included “All others” as part of the Company’s one reportable segment. The historical activity of the reportable segment and “All others” has been recast for consistent presentation for all periods presented.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Reclassification

Certain prior period footnote amounts have been re-cast to reflect the effect of the changes to the Company's identified operating segments. See Note 16.