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Verification Methods Of Snubber Circuits in Flyback Converters


The demand having a snubber circuit in the power supply topology leads to specific verification methods during the design to obtain a proper and reliable design. Learn how in this AppNote.

Most of the existing electronic devices are connected to the AC mains and require a power conversion stage to convert the AC-Voltage to a smaller DC-Voltage. Voltages and frequencies of the power grid differ between different regions. However, different types of AC-DC conversion stages exist to supply the electronic equipment with adequate DC-power.

In AC-DC conversion combined with power levels less than 50W, the flyback converter is a commonplace chosen topology because of its simplicity and its low cost. The majority of consumer products make use of this converter type like wall brick power supplies or power adapters for any consumer application and other type of stand-by auxiliary power supply like used in white and brown goods. In AC to DC converter application, an electrical isolation between input and output is mandatory.

Beside the common advantages of a flyback converter, it has inherently parasitic components, which typically produce ringing waveforms with considerably high voltage spikes. Without suppressing this unwanted ringing, it may have some negative effect on other components like the switching elements. This ringing can also influence the EMI emissions adversely. Therefore, it is an important task to adequate suppress and damp the ringing effect. This damping circuit is known as snubber circuit and provides this functionality. In the flyback converter, different snubber structures can be applied and each of the structure has its advantage and disadvantage.

With this AppNote you will learn:

  • Verification methods of snubber circuits in flyback converter
  • the performance and usage of Rohde & Schwarz oscilloscopes and power supplies for such measurements
  • the importance for power electronic testing
  • solutions to obtain a proper and reliable design

The provider of this whitepaper

Rohde & Schwarz GmbH & Co. KG

Mühldorfstr. 15
81671 München



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