Electronic engineers value relevant resources when designing their applications, thus RECOM commissioned a book addressing the modern challenges of developing an application with AD/DC converters. This book expands upon and discusses the theory of AC/DC conversion in 13 comprehensive, yet concise chapters. These chapters cover a wide variety of topics such as a historical introduction to AC voltage, exploring passive and active components—including IGBT, SiC MOSFET, and GaN gate drivers, power factor correction, AC/DC converter topologies, and low standby power consumption techniques relevant for IoT applications. The text also includes relevant reference schematic and block diagrams examples within each chapter.