The main part of the noise generated by the switching power supply is the power conversion and output rectification and filtering circuit. Including switch tubes, rectifiers, transformers, and output choke coils, etc.
The peak value of the output voltage when no measures are taken may be many times the output fundamental. Appears on the rising and falling edges of the switching pulse. That is, the switching tube is turned on and off, and the peak is usually larger when it is turned on.
10 ways to suppress the peak of the rectifier diode!Some suppression methods for leading edge spikes
1 Select the Schottky diode with soft recovery characteristics, or use the method of series inductance in front of the rectifier tube, or the magnetic beads in the rectifier tube of the switching tube. The core material is made of a ferrite material having a high impedance attenuation characteristic for high-frequency oscillation, and the like.
2 Connecting the RC absorption loop on the secondary side can further reduce the amplitude of the leading edge peak and reduce the oscillation frequency during diode recovery.
More than 3 rectifier diodes are connected in parallel; appropriately increasing the current capacity of the rectifier diode can relatively reduce the off time during reverse recovery, limit the value of the reverse short circuit current, and suppress current spikes and reduce conduction loss.
4 Try to make the component layout trace reasonable, reduce the area of ​​the large current loop, and suppress the EMI.
Method for suppressing the trailing edge spike
5 select the rectifier diode with fast switching speed
6Select high magnetic permeability core, the excitation current is as small as possible during transformer design
7 Use high magnetic flux density materials to ensure that the transformer will not saturate in harsh environments. Can take B value as half or 1/3 of the saturation value
8 Select the closed magnetic circuit can or PQ core to reduce leakage.
9 high frequency transformer winding to minimize leakage inductance. Use a sandwich winding method or a sandwich rounding method. The windings are distributed as evenly as possible on the skeleton. Skin effect should be considered when using enameled wire.
10 Parallel RC absorption loop between the DSs of the switching tubes.
We've been around for over 16+ years. We make sure our sound is The Best Sound.
Manufacturing high-quality products for customers according to international standards, such as CE ROHS FCC REACH UL SGS BQB etc.
wholesale earbuds, earbuds in bulk, earbuds custom, true wireless earbuds
TOPNOTCH INTERNATIONAL GROUP LIMITED , https://www.itopnoobluetoothes.com