Organization and Basis of Presentation	9 Months Ended
Oct. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation Nature of Business 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 other quarters generally end on the last Sunday of April, July and October. All quarters consist of 13 weeks except for one 14-week period in the fourth quarter of 53-week years. The third quarter of fiscal years 2017 and 2016 each consisted of 13 weeks. Principles of Consolidation The accompanying interim unaudited condensed consolidated financial statements have been prepared by the Company, in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and the instructions to quarterly report on Form 10-Q under the Securities Exchange Act of 1934, as amended, and Article 10 of Regulation S-X. In the opinion of the Company, these unaudited statements contain all adjustments (consisting of normal recurring adjustments) necessary to present fairly, in all material respects, the financial position of the Company for the interim periods presented. All significant intercompany balances have been eliminated. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations, and the Company believes that the included disclosures are adequate to make the information presented not misleading. The Company evaluated all subsequent events through the date these interim unaudited condensed consolidated financial statements were issued. 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 selected assets from EnVerv, Inc. (“EnVerv”). The interim unaudited condensed consolidated financial statements include the results of income of Triune and EnVerv commencing as of the acquisition dates. These interim unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto included in the Company’s Annual Report on Form 10-K for the year ended January 31, 2016. The results reported in these interim unaudited condensed consolidated financial statements should not be regarded as indicative of results that may be expected for any subsequent period or for the entire year. 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 14 for further discussion). In fiscal year 2016, the Company updated its assessment of its operations in light of its restructuring efforts (see Note 17 for further discussion) and strategic business decisions. Based on this assessment, at that time the Company had identified five operating segments in total. Four of the operating segments aggregated 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 was reported separately from the Company’s Semiconductor Products Group. This separate reporting was included in the “All others” category. On August 5, 2016, the Company completed its divestiture of its Snowbush Intellectual Property (“Snowbush IP”) business (previously part of the Company’s Systems Innovation Group) to Rambus Inc. (“Rambus”) for a purchase price of $32.0 million in cash along with the opportunity to receive additional payments from Rambus through 2022 based upon a percentage of sales by Rambus of new products expected to be developed by Rambus from the disposed assets. Beginning in the third quarter of fiscal year 2017, the Company no longer has a Systems Innovation Group or an “All others” category, and therefore has only four operating segments that aggregate into one reportable segment, the Semiconductor Products Group. Use of Estimates The preparation of financial statements in conformity with 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. Derivatives and Hedging Activities Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 815, Derivatives and Hedging, provides the disclosure requirements for derivatives and hedging activities with the intent to provide users of financial statements with an enhanced understanding of: (a) how and why an entity uses derivative instruments, (b) how the entity accounts for derivative instruments and related hedged items, and (c) how derivative instruments and related hedged items affect an entity’s financial position, financial performance, and cash flows. Further, qualitative disclosures are required that explain the Company’s objectives and strategies for using derivatives, as well as quantitative disclosures about the fair value of and gains and losses on derivative instruments, and disclosures about credit-risk-related contingent features in derivative instruments. As required by ASC 815, the Company records all derivatives on the balance sheet at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative, whether the Company has elected to designate a derivative in a hedging relationship and apply hedge accounting and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. Derivatives designated and qualifying as a hedge of the exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Hedge accounting generally provides for the matching of the timing of gain or loss recognition on the hedging instrument with the recognition of the changes in the fair value of the hedged asset or liability that are attributable to the hedged risk in a fair value hedge or the earnings effect of the hedged forecasted transactions in a cash flow hedge. The Company may enter into derivative contracts that are intended to economically hedge certain of its risk, even though hedge accounting does not apply or the Company elects not to apply hedge accounting. In accordance with the FASB’s fair value measurement guidance, the Company made an accounting policy election to measure the credit risk of its derivative financial instruments that are subject to master netting agreements on a net basis by counterparty portfolio. Recent Accounting Pronouncements On August 26, 2016, the FASB issued Accounting Standards Update (“ASU”) 2016-15, “Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments.” The primary purpose of this ASU is to reduce the diversity in practice that has resulted from the lack of consistent principles on this topic. This ASU is effective for fiscal years beginning after December 15, 2017. This ASU will be effective for the Company as of the beginning of Fiscal 2019. Early adoption is permitted in any interim or annual period. The Company is in the process of determining the impact of the adoption of this guidance on its consolidated financial statements or notes thereto; however, it does not anticipate that the new guidance will have a significant impact on its consolidated financial statements. In February 2016, FASB issued ASU No. 2016-02, Leases (Topic 842), which will require that substantially all leases be recognized by lessees on their balance sheet as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases. The new standard also will result in enhanced quantitative and qualitative disclosures, including significant judgments made by management, to provide greater insight into the extent of revenue and expense recognized and expected to be recognized from existing leases. The standard requires modified retrospective adoption and will be effective December 15, 2018, with early adoption permitted. The Company does not expect the adoption of this update to have a material impact on its consolidated financial statements. In July 2015, the FASB issued ASU 2015-11, Inventory (Topic 330) Related to Simplifying the Measurement of Inventory which will apply to all inventory except inventory that is measured using last-in, first-out (“LIFO”) or the retail inventory method. Inventory measured using first-in, first-out or average cost is covered by the new amendments. Inventory within the scope of the new guidance should be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. Subsequent measurement is unchanged for inventory measured using LIFO or the retail inventory method. The amendments will take effect for public business entities for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. The new guidance should be applied prospectively, and earlier application is permitted as of the beginning of an interim or annual reporting period. The Company is currently assessing the impact this update will have on its consolidated financial statements. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), which will require an entity to recognize revenue from the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The guidance addresses, in particular, contracts with more than one performance obligation, as well as the accounting for some costs to obtain or fulfill a contract with a customer, and provides for additional disclosures with respect to revenues and cash flows arising from contracts with customers. Public entities are required to apply the amendments on either a full- or modified-retrospective basis for annual periods beginning after December 15, 2017 and for interim periods within those annual periods. This update will be effective for the Company beginning in the first quarter of fiscal year 2019. Early adoption is not permitted. The Company is currently assessing the basis of adoption and evaluating the impact of the adoption of the update on its consolidated financial statements.

Organization and Basis of Presentation

Nature of Business

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 other quarters generally end on the last Sunday of April, July and October. All quarters consist of 13 weeks except for one 14-week period in the fourth quarter of 53-week years. The third quarter of fiscal years 2017 and 2016 each consisted of 13 weeks.

Principles of Consolidation

The accompanying interim unaudited condensed consolidated financial statements have been prepared by the Company, in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and the instructions to quarterly report on Form 10-Q under the Securities Exchange Act of 1934, as amended, and Article 10 of Regulation S-X. In the opinion of the Company, these unaudited statements contain all adjustments (consisting of normal recurring adjustments) necessary to present fairly, in all material respects, the financial position of the Company for the interim periods presented. All significant intercompany balances have been eliminated. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations, and the Company believes that the included disclosures are adequate to make the information presented not misleading. The Company evaluated all subsequent events through the date these interim unaudited condensed consolidated financial statements were issued.

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 selected assets from EnVerv, Inc. (“EnVerv”). The interim unaudited condensed consolidated financial statements include the results of income of Triune and EnVerv commencing as of the acquisition dates.

These interim unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto included in the Company’s Annual Report on Form 10-K for the year ended January 31, 2016. The results reported in these interim unaudited condensed consolidated financial statements should not be regarded as indicative of results that may be expected for any subsequent period or for the entire year.

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 14 for further discussion). In fiscal year 2016, the Company updated its assessment of its operations in light of its restructuring efforts (see Note 17 for further discussion) and strategic business decisions. Based on this assessment, at that time the Company had identified five operating segments in total. Four of the operating segments aggregated 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 was reported separately from the Company’s Semiconductor Products Group. This separate reporting was included in the “All others” category. On August 5, 2016, the Company completed its divestiture of its Snowbush Intellectual Property (“Snowbush IP”) business (previously part of the Company’s Systems Innovation Group) to Rambus Inc. (“Rambus”) for a purchase price of $32.0 million in cash along with the opportunity to receive additional payments from Rambus through 2022 based upon a percentage of sales by Rambus of new products expected to be developed by Rambus from the disposed assets. Beginning in the third quarter of fiscal year 2017, the Company no longer has a Systems Innovation Group or an “All others” category, and therefore has only four operating segments that aggregate into one reportable segment, the Semiconductor Products Group.

Use of Estimates

The preparation of financial statements in conformity with 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.

Derivatives and Hedging Activities

Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 815, Derivatives and Hedging, provides the disclosure requirements for derivatives and hedging activities with the intent to provide users of financial statements with an enhanced understanding of: (a) how and why an entity uses derivative instruments, (b) how the entity accounts for derivative instruments and related hedged items, and (c) how derivative instruments and related hedged items affect an entity’s financial position, financial performance, and cash flows. Further, qualitative disclosures are required that explain the Company’s objectives and strategies for using derivatives, as well as quantitative disclosures about the fair value of and gains and losses on derivative instruments, and disclosures about credit-risk-related contingent features in derivative instruments.

As required by ASC 815, the Company records all derivatives on the balance sheet at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative, whether the Company has elected to designate a derivative in a hedging relationship and apply hedge accounting and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. Derivatives designated and qualifying as a hedge of the exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Hedge accounting generally provides for the matching of the timing of gain or loss recognition on the hedging instrument with the recognition of the changes in the fair value of the hedged asset or liability that are attributable to the hedged risk in a fair value hedge or the earnings effect of the hedged forecasted transactions in a cash flow hedge. The Company may enter into derivative contracts that are intended to economically hedge certain of its risk, even though hedge accounting does not apply or the Company elects not to apply hedge accounting.

In accordance with the FASB’s fair value measurement guidance, the Company made an accounting policy election to measure the credit risk of its derivative financial instruments that are subject to master netting agreements on a net basis by counterparty portfolio.

Recent Accounting Pronouncements

On August 26, 2016, the FASB issued Accounting Standards Update (“ASU”) 2016-15, “Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments.” The primary purpose of this ASU is to reduce the diversity in practice that has resulted from the lack of consistent principles on this topic. This ASU is effective for fiscal years beginning after December 15, 2017. This ASU will be effective for the Company as of the beginning of Fiscal 2019. Early adoption is permitted in any interim or annual period. The Company is in the process of determining the impact of the adoption of this guidance on its consolidated financial statements or notes thereto; however, it does not anticipate that the new guidance will have a significant impact on its consolidated financial statements.

In February 2016, FASB issued ASU No. 2016-02, Leases (Topic 842), which will require that substantially all leases be recognized by lessees on their balance sheet as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases. The new standard also will result in enhanced quantitative and qualitative disclosures, including significant judgments made by management, to provide greater insight into the extent of revenue and expense recognized and expected to be recognized from existing leases. The standard requires modified retrospective adoption and will be effective December 15, 2018, with early adoption permitted. The Company does not expect the adoption of this update to have a material impact on its consolidated financial statements.

In July 2015, the FASB issued ASU 2015-11, Inventory (Topic 330) Related to Simplifying the Measurement of Inventory which will apply to all inventory except inventory that is measured using last-in, first-out (“LIFO”) or the retail inventory method. Inventory measured using first-in, first-out or average cost is covered by the new amendments. Inventory within the scope of the new guidance should be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. Subsequent measurement is unchanged for inventory measured using LIFO or the retail inventory method. The amendments will take effect for public business entities for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. The new guidance should be applied prospectively, and earlier application is permitted as of the beginning of an interim or annual reporting period. The Company is currently assessing the impact this update will have on its consolidated financial statements.

In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), which will require an entity to recognize revenue from the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The guidance addresses, in particular, contracts with more than one performance obligation, as well as the accounting for some costs to obtain or fulfill a contract with a customer, and provides for additional disclosures with respect to revenues and cash flows arising from contracts with customers. Public entities are required to apply the amendments on either a full- or modified-retrospective basis for annual periods beginning after December 15, 2017 and for interim periods within those annual periods. This update will be effective for the Company beginning in the first quarter of fiscal year 2019. Early adoption is not permitted. The Company is currently assessing the basis of adoption and evaluating the impact of the adoption of the update on its consolidated financial statements.