Lineaarisäätimet

Lineaarisäätimet, often translated as linear regulators, are electronic components used to convert a variable input voltage into a stable, constant output voltage. They are a fundamental part of many electronic power supply circuits. The primary function of a linear regulator is to maintain a fixed output voltage regardless of fluctuations in the input voltage or changes in the load current.

The operation of a linear regulator relies on a voltage drop across a control element, typically a transistor, which acts as a variable resistor. A feedback loop monitors the output voltage and adjusts the resistance of the control element to keep the output constant. If the output voltage starts to rise, the regulator increases its internal resistance, dissipating more power and reducing the output voltage. Conversely, if the output voltage drops, the regulator decreases its resistance, allowing more current to flow and raising the output voltage.

Lineaarisäätimet are known for their simplicity, low noise output, and fast transient response, making them suitable for sensitive analog circuits. However, they are also inefficient, especially when there is a large difference between the input and output voltages. This inefficiency leads to significant power dissipation in the form of heat, often requiring heat sinks for higher current applications. Despite their limitations, lineaarisäätimet remain a popular choice for low-power, noise-sensitive applications where efficiency is not a primary concern.