Organization and Basis of Presentation	9 Months Ended
Oct. 28, 2018
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 consolidated subsidiaries, the "Company" or "Semtech") is a global supplier of analog and mixed-signal semiconductors and advanced algorithms. The end customers for the Company’s products are primarily original equipment manufacturers ("OEMs") 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, 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, monitors and displays, tablets, wearables, digital video recorders and other consumer equipment. Industrial: analog and digital video broadcast equipment, video-over-IP solutions, automated meter reading, Internet of Things ("IoT"), smart grid, wireless charging, military and aerospace, medical, security systems, automotive, industrial and home automation 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 2019 and 2018 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") and on the same basis as the audited consolidated financial statements included in the Company’s Annual Report on Form 10-K for the fiscal year ended January 28, 2018 ("Annual Report"). In the opinion of the Company, these interim unaudited condensed consolidated financial 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 intercompany balances have been eliminated. Certain information and footnote disclosures normally included in annual consolidated financial statements have been condensed or omitted pursuant to the rules and regulations of the U.S. Securities and Exchange Commission. Because the interim unaudited condensed consolidated financial statements do not include all of the information and notes required by GAAP for a complete set of consolidated financial statements, they should be read in conjunction with the audited consolidated financial statements and notes included in the Company's Annual Report. 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. The Company’s interim unaudited condensed consolidated statements of income are referred to herein as the "Statements of Income." The Company’s interim unaudited condensed consolidated balance sheets are referred to herein as the "Balance Sheets" and interim unaudited condensed consolidated statements of cash flows as the "Statements of Cash Flows." 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 12 for further discussion). Prior to the first quarter of fiscal year 2019, the Company had four operating segments that aggregated into one reportable segment. Beginning with the first quarter of fiscal year 2019, the Company identified three 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. Acquisitions On August 17, 2018, the Company, through its subsidiary Semtech (International) AG, a Swiss corporation, entered into a share purchase agreement to purchase all of the outstanding equity interests of Trackio International AG, a Swiss corporation, and its subsidiaries (collectively, "TrackNet"), for an aggregate purchase price of approximately $8.5 million (the "TrackNet Acquisition"). The purchase price is expected to be funded by cash on hand. The closing of the TrackNet Acquisition is subject to customary conditions and certain regulatory approvals. In connection with the signing of the TrackNet Acquisition, the employees of TrackNet have become employees or independent contractors of the Company. In addition, TrackNet entered into an agreement under which key TrackNet intellectual property has been licensed to the Company. As a result, control of TrackNet's business transferred to the Company during the third quarter of fiscal year 2019. The amount payable to TrackNet has been treated as contingent consideration since the payment of this amount is dependent upon regulatory approval, which the Company expects to receive during the fourth quarter of fiscal year 2019. The transaction was accounted for as a business combination and the entire purchase price of $8.5 million has been preliminarily attributed to goodwill (see Note 8). The Company is still in the process of determining the final purchase price allocation. On May 2, 2018, the Company acquired substantially all the assets of IC Interconnect, Inc. (“ICI”) for a cash payment of approximately $7.3 million. The addition of ICI is aimed at further enhancing the Company’s U.S. research and development capabilities for its next-generation Z-Pak platform. $4.8 million was attributed to goodwill (see Note 8) and $2.5 million was attributed to the estimated fair values of the tangible net assets acquired. The goodwill is deductible for tax purposes. The transaction was accounted for as a business combination and we are still assessing the purchase price allocation. Net revenues, earnings and pro forma results of operations have not been presented because they are not material to the Company’s consolidated financial statements. Settlements On August 1, 2018, the Company announced the settlement of a lawsuit filed against HiLight Semiconductor Limited and related individual defendants in accordance with which the Company is to be paid approximately $9.0 million to cover damages for claims, costs and attorneys' fees. Approximately $6.6 million was received during the second quarter of fiscal year 2019, and is presented within "Selling, general and administrative" ("SG&A") in the Statements of Income. Recent Accounting Standards Adopted In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-09, Revenue from Contracts with Customers (Accounting Standards Codification ("ASC") 606), which requires an entity to recognize revenue from the transfer of control 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. The Company adopted the standard, effective January 29, 2018, using the modified retrospective transition method which resulted in an adjustment to retained earnings for the cumulative effect of applying the standard to all contracts not completed as of the adoption date. The primary change associated with the adoption relates to the Company’s sales to distributors with return or price adjustment rights where the Company will no longer defer revenue until the resale by the distributor to the end customer, but rather, will record revenue at the time control transfers to the distributor. The Company estimated the effects of returns and allowances provided to these distributors. Upon adoption, including the effect of income taxes, opening retained earnings as of January 29, 2018 increased by $11.1 million net, as a result of these changes. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. In October 2016, the FASB issued ASU No. 2016-16, Intra-Entity Asset Transfers Other Than Inventory (Topic 740). This accounting standard update is aimed at recognizing the income tax consequences of intra-entity transfers of assets other than inventory when they occur. This removes the exception to postpone the recognition of income tax consequences of intra-entity transfers until the asset has been sold to an outside party. In the first quarter of 2019, the Company adopted ASU 2016-16 using a modified retrospective transition method, resulting in a $1.8 million decrease in retained earnings, a $3.7 million net increase in deferred income tax assets, and a $5.5 million decrease in pre-paid taxes. In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments (Topic 230). 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. In the first quarter of fiscal year 2019, the Company adopted ASU 2016-15. Accounting Guidance Issued but Not Adopted as of October 28, 2018 In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), which will require that substantially all leases be recognized by lessees on their balance sheets as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases with the exception of short-term leases. Public entities are required to apply the amendments for annual periods beginning after December 15, 2018 and for interim periods within those annual periods. The Company will adopt this update beginning in the first quarter of fiscal year 2020 utilizing the modified retrospective transition method by recognizing a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. The Company expects to elect certain practical expedients permitted under the transition guidance within the standard. The Company is currently in the process of determining the impact that the updated accounting guidance will have on its consolidated financial statements.

Organization and Basis of Presentation

Nature of Business

Semtech Corporation (together with its consolidated subsidiaries, the "Company" or "Semtech") is a global supplier of analog and mixed-signal semiconductors and advanced algorithms. The end customers for the Company’s products are primarily original equipment manufacturers ("OEMs") 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, 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, monitors and displays, tablets, wearables, digital video recorders and other consumer equipment.

Industrial: analog and digital video broadcast equipment, video-over-IP solutions, automated meter reading, Internet of Things ("IoT"), smart grid, wireless charging, military and aerospace, medical, security systems, automotive, industrial and home automation 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 2019 and 2018 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") and on the same basis as the audited consolidated financial statements included in the Company’s Annual Report on Form 10-K for the fiscal year ended January 28, 2018 ("Annual Report"). In the opinion of the Company, these interim unaudited condensed consolidated financial 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 intercompany balances have been eliminated. Certain information and footnote disclosures normally included in annual consolidated financial statements have been condensed or omitted pursuant to the rules and regulations of the U.S. Securities and Exchange Commission. Because the interim unaudited condensed consolidated financial statements do not include all of the information and notes required by GAAP for a complete set of consolidated financial statements, they should be read in conjunction with the audited consolidated financial statements and notes included in the Company's Annual Report. 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.

The Company’s interim unaudited condensed consolidated statements of income are referred to herein as the "Statements of Income." The Company’s interim unaudited condensed consolidated balance sheets are referred to herein as the "Balance Sheets" and interim unaudited condensed consolidated statements of cash flows as the "Statements of Cash Flows."

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 12 for further discussion). Prior to the first quarter of fiscal year 2019, the Company had four operating segments that aggregated into one reportable segment. Beginning with the first quarter of fiscal year 2019, the Company identified three 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.

Acquisitions

On August 17, 2018, the Company, through its subsidiary Semtech (International) AG, a Swiss corporation, entered into a share purchase agreement to purchase all of the outstanding equity interests of Trackio International AG, a Swiss corporation, and its subsidiaries (collectively, "TrackNet"), for an aggregate purchase price of approximately $8.5 million (the "TrackNet Acquisition"). The purchase price is expected to be funded by cash on hand. The closing of the TrackNet Acquisition is subject to customary conditions and certain regulatory approvals. In connection with the signing of the TrackNet Acquisition, the employees of TrackNet have become employees or independent contractors of the Company. In addition, TrackNet entered into an agreement under which key TrackNet intellectual property has been licensed to the Company. As a result, control of TrackNet's business transferred to the Company during the third quarter of fiscal year 2019. The amount payable to TrackNet has been treated as contingent consideration since the payment of this amount is dependent upon regulatory approval, which the Company expects to receive during the fourth quarter of fiscal year 2019. The transaction was accounted for as a business combination and the entire purchase price of $8.5 million has been preliminarily attributed to goodwill (see Note 8). The Company is still in the process of determining the final purchase price allocation.

On May 2, 2018, the Company acquired substantially all the assets of IC Interconnect, Inc. (“ICI”) for a cash payment of approximately $7.3 million. The addition of ICI is aimed at further enhancing the Company’s U.S. research and development capabilities for its next-generation Z-Pak platform. $4.8 million was attributed to goodwill (see Note 8) and $2.5 million was attributed to the estimated fair values of the tangible net assets acquired. The goodwill is deductible for tax purposes. The transaction was accounted for as a business combination and we are still assessing the purchase price allocation.

Net revenues, earnings and pro forma results of operations have not been presented because they are not material to the Company’s consolidated financial statements.

Settlements

On August 1, 2018, the Company announced the settlement of a lawsuit filed against HiLight Semiconductor Limited and related individual defendants in accordance with which the Company is to be paid approximately $9.0 million to cover damages for claims, costs and attorneys' fees. Approximately $6.6 million was received during the second quarter of fiscal year 2019, and is presented within "Selling, general and administrative" ("SG&A") in the Statements of Income.

Recent Accounting Standards Adopted

In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-09, Revenue from Contracts with Customers (Accounting Standards Codification ("ASC") 606), which requires an entity to recognize revenue from the transfer of control 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.

The Company adopted the standard, effective January 29, 2018, using the modified retrospective transition method which resulted in an adjustment to retained earnings for the cumulative effect of applying the standard to all contracts not completed as of the adoption date. The primary change associated with the adoption relates to the Company’s sales to distributors with return or price adjustment rights where the Company will no longer defer revenue until the resale by the distributor to the end customer, but rather, will record revenue at the time control transfers to the distributor. The Company estimated the effects of returns and allowances provided to these distributors. Upon adoption, including the effect of income taxes, opening retained earnings as of January 29, 2018 increased by $11.1 million net, as a result of these changes. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods.

In October 2016, the FASB issued ASU No. 2016-16, Intra-Entity Asset Transfers Other Than Inventory (Topic 740). This accounting standard update is aimed at recognizing the income tax consequences of intra-entity transfers of assets other than inventory when they occur. This removes the exception to postpone the recognition of income tax consequences of intra-entity transfers until the asset has been sold to an outside party. In the first quarter of 2019, the Company adopted ASU 2016-16 using a modified retrospective transition method, resulting in a $1.8 million decrease in retained earnings, a $3.7 million net increase in deferred income tax assets, and a $5.5 million decrease in pre-paid taxes.

In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments (Topic 230). 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. In the first quarter of fiscal year 2019, the Company adopted ASU 2016-15.

Accounting Guidance Issued but Not Adopted as of October 28, 2018

In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), which will require that substantially all leases be recognized by lessees on their balance sheets as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases with the exception of short-term leases. Public entities are required to apply the amendments for annual periods beginning after December 15, 2018 and for interim periods within those annual periods. The Company will adopt this update beginning in the first quarter of fiscal year 2020 utilizing the modified retrospective transition method by recognizing a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. The Company expects to elect certain practical expedients permitted under the transition guidance within the standard. The Company is currently in the process of determining the impact that the updated accounting guidance will have on its consolidated financial statements.