Offline Flyback
Connector
Rocker Switch
Rocker switches create electrical connections and disconnect them again for currents of several amperes. A typical area of application here is the on/off switch for power supplies. Due to their exposure and safety-critical function, they often require compliance with stringent quality standards. IEC/UL 61058, glow wire, UV tests according to IEC60068-2-5, as well as additional reliability tests ensure compliance.
Mains Filter
A line filter reduces interference between the device and the power supply. This means that, on the one hand, disturbances from the mains do not couple into the device (increasing immunity to interference), and on the other hand, disturbances from the device do not reach the mains (reducing emitted interference).
Input Capacitor
Selecting the right input capacitor requires consider not only the rated voltage but also the impedance at the operating frequency of the switching regulator.
Switch
A higher switching frequency will enable smaller Inductors and smaller filter components. However, radiated EMI might increase.
Thermal Management
Thermal management is of importance in order to guarantee reliability and longevity of electronic devices and components.
RCD-Snubber
Snubber circuits protect against transient voltages that occur during turn-off and also have a positive impact on conducted Emissions.
Offline Transformer
Flyback-Converters have the advantage of offering two or more output voltages. Offline Transformers are designed for AC/DC Switching regulators and therefore have reinforced Isolation.
Custom Solutions Possible
Our engineers are waiting to create a transformer that’s as unique as your application, with personalized details, and a range of options dialed in to exactly what you need.
Thermal Management
Thermal management is of importance in order to guarantee reliability and longevity of electronic devices and components.
Output Capacitor
For lower ESR, aluminum polymer capacitors are recommended for bulk capacitors. Conventional electrolytic capacitors are suitable as well.
Filter Cut-Off Frequency
The filter’s cut-off frequency should be about one tenth of the converter’s switching frequency. Please consider the SRF of all filter components. Use the REDEXPERT Filter Designer to design an EMI filter and evaluate the realistic response based on real components.
Line Filter
Differential mode noise < 30MHz is best attenuated by ferrite based chokes.
Common Mode Choke
For common-mode interference below 30 MHz, ferrite chokes are the most suitable.
Connector
Short Introduction to Offline Flyback
The flyback converter is a simple isolated switching regulator topology. ”Offline” in this context means that the converter is not operated directly on mains voltage, but behind a rectifier.
For use in protection class II applications, the transformer is designed with reinforced insulation. The isolated output feedback can be acquired either directly from a winding of the transformer or by using an optocoupler.
The flyback is the simplest solution for an isolated switching power supply (SMPS) with low power output. For power ratings above 50 W, other topologies offer better efficiency.
