Kytkinlähteet

Kytkinlähteet, or switching power supplies, are electronic power supplies that regulate voltage by switching an inductor or transformer between charging and discharging states. This on/off switching action is performed at high frequencies, typically in the tens of kilohertz or even megahertz range. By controlling the duty cycle of this switching, the output voltage can be precisely regulated. This method is significantly more efficient than linear voltage regulators, which dissipate excess voltage as heat.

The main components of a switching power supply include a rectifier, a filter, a switching element (usually a transistor), a transformer (often a high-frequency transformer), and a control circuit. The input AC voltage is first rectified to DC and filtered. The switching element then chops this DC voltage at a high frequency. This chopped waveform is applied to a transformer, which can step up or step down the voltage. Finally, the output of the transformer is rectified and filtered again to produce a stable DC output voltage. The control circuit monitors the output voltage and adjusts the duty cycle of the switching element to maintain the desired output.

Switching power supplies are widely used due to their high efficiency, small size, and light weight compared to linear power supplies. They are found in a vast array of electronic devices, including computer power supplies, chargers for mobile devices, televisions, and industrial equipment. However, they can generate electromagnetic interference (EMI) due to their high-frequency switching operation, which often requires additional filtering to mitigate.