Introduction to Switching Power Supply Noise Solutions
1. Reduce parallel noise of capacitors
The parallel connection of capacitors in switch mode power supplies is the main source of high-frequency noise. In order to reduce the noise caused by capacitor parallel connection, the following measures need to be taken:
(1) Using organic electrolytic capacitors: Organic electrolytic capacitors have a relatively small capacitance, and the corresponding noise generated is also small.
(2) Using multiple small capacitance capacitors in parallel: Multiple small capacitance capacitors in parallel can share the noise generated by capacitor parallel connection.
(3) Using an independent power supply: An independent power supply can effectively reduce the noise generated by parallel capacitors.
2. Strengthen shielding
Shielding is an effective noise reduction method, and by using appropriate shielding materials, interference from electronic devices and the surrounding environment can be effectively reduced.
(1) Improve shielding performance: Choose shielding materials with good shielding performance, such as ferromagnetic materials, aluminum foil, copper foil, etc.
(2) Increase shielding layers: When one layer of shielding is insufficient to meet the requirements in critical areas, additional shielding layers can be added on top of the original ones.
3. Reduce driving voltage noise
The driving voltage of a switching power supply is one of the main factors that generate noise. In order to reduce the noise of the driving voltage, the following measures can be taken:
(1) Choosing a suitable power supply: Choosing a power supply with more stable performance can greatly reduce the noise generated by switching power supplies.
(2) Reduce the noise of driving voltage: The noise of driving voltage can be reduced through power filtering capacitors, magnetic beads, torque magnetic rings, TLPI networks, and other methods.
4. Reduce inductor leakage noise
Inductive leakage is also one of the causes of noise in switching power supplies. To reduce the leakage noise of inductors, the following measures can be taken:
(1) Choosing high-quality inductors: Using high-quality raw materials for inductors can greatly reduce the leakage noise of inductors.
(2) Adopting magnetic shielding technology: By using magnetic shielding technology in key areas, the noise generated by inductance leakage can be effectively reduced.
