Kytkentävirtalähde

Kytkentävirtalähde, also known as a switching power supply or SMPS (Switched-Mode Power Supply), is a type of electronic power supply that uses a switching regulator to convert electrical power efficiently. Unlike linear power supplies, which dissipate excess voltage as heat, kytkentävirtalähde rapidly switches its input voltage on and off at high frequencies. This on-off cycling, typically in the tens or hundreds of kilohertz, is controlled by a feedback loop that adjusts the duty cycle of the switching element to maintain a stable output voltage.

The core components of a kytkentävirtalähde include a transformer, which is often smaller and lighter than those used in linear supplies due to the high operating frequencies, a switching element (like a MOSFET or BJT), a rectifier, and a filter. The high-frequency switching allows for smaller passive components like inductors and capacitors, contributing to a more compact and lightweight design. This efficiency also means less heat is generated, reducing the need for large heatsinks.

Kytkentävirtalähteet are widely used in modern electronics due to their high efficiency, compact size, and light weight. They are commonly found in devices such as computer power supplies, mobile phone chargers, televisions, and industrial equipment. While generally reliable, they can sometimes introduce electromagnetic interference (EMI) due to their high-frequency switching operation, requiring careful design and shielding. The output ripple, or fluctuations in the DC output voltage, can also be a consideration, though filtering techniques are employed to minimize this.