Exhibit 21.1

Subsidiaries of Semtech Corporation

• Gennum US Holdings Limited (Delaware)

• Gennum US Limited (Delaware)

• Semtech Corpus Christi Corporation (Texas)

• Semtech New York Corporation (Delaware)

• Semtech San Diego Corporation (California)

• Sierra Monolithics, Inc. (California)

• Gennum Canada ULC (Nova Scotia, Canada)

• Semtech Canada Corporation (Nova Scotia, Canada)

• Semtech Semiconductor (Chengdu) Co. Ltd. (China)

• Semtech Semiconductor (Shanghai) Co. Ltd. (China)

• Semtech Semiconductor (Shenzhen) Company Limited (China)

• Cycleo SAS (France)

• Nanoscale SAS (France)

• Semtech France SARL (France)

• Semtech Holdings France SAS (France)

• Semtech Germany GmbH (Germany)

• Semtech Semiconductor Holdings Limited (Hong Kong)

• Semtech Advanced Systems India Private Limited (India)

• Gennum Japan Kabushiki Kaisha (Japan)

• Semtech Semiconductor (Malaysia) Sdn Bhd

• Semtech Corpus Christi S.A. de CV (Mexico)

• Snowbush Mexico S.A.P.I. de C.V. – 99.9%

• Semtech Netherlands BV (Netherlands)

• Semtech (International) AG (Switzerland)

• Semtech Neuchatel SARL (Switzerland)

• Semtech Switzerland GmbH (Switzerland)

• Gennum UK Limited (United Kingdom)

• Nanotech Semiconductor Limited (United Kingdom)

• Semtech EMEA Ltd (United Kingdom)

• Semtech Limited (United Kingdom)