lineaarregulaator

A lineaarregulaator, commonly known as a linear regulator, is an electronic device that provides a stable, regulated voltage output from a varying or noisy input voltage. It operates by dissipating excess energy as heat, maintaining a constant output regardless of changes in load current or input voltage within specified limits. The basic principle involves a device such as a transistor, MOSFET, or bipolar junction transistor acting as a variable resistor controlled by an internal feedback loop. This loop senses the output voltage and adjusts the resistance to keep the voltage at a predetermined set point.

Linear regulators are classified mainly into two groups: linear voltage regulators and linear voltage regulators with adjustable output. Fixed regulators provide a single output voltage, typically between 1.8 V and 12 V, while adjustable regulators allow the output to be set by external resistors. Common families include the 78xx series of positive regulators and the 79xx series of negative regulators, as well as low-dropout (LDO) regulators that can operate with a very small difference between input and output voltage.

The key advantages of lineaarregulaators are their simplicity, low output noise, and good load and line regulation. However, they are inefficient when the input-to-output voltage difference is large, since the difference is dissipated as heat. Therefore, they are often employed in low-power applications, precision analog circuits, and situations where noise performance is critical. Typical uses include powering microcontroller analog references, providing reference voltages for precision measurement, and supplying low-speed motor controllers.