shuntsäätimet

Shuntsäätimet, often referred to as shunt regulators, are electronic components used to control voltage. They work by diverting excess current away from a load, thereby maintaining a stable voltage across it. This is achieved by using a transistor, typically a bipolar junction transistor (BJT) or a MOSFET, which acts as a variable resistor. A reference voltage is compared to the output voltage, and any difference is used to adjust the conductivity of the transistor. If the output voltage is too high, the transistor becomes more conductive, shunting more current away from the load and lowering the voltage. Conversely, if the output voltage is too low, the transistor becomes less conductive, allowing more current to flow to the load and increasing the voltage.

Shuntsäätimet are commonly employed in applications where a precise and stable voltage is required, such as in power supplies, battery chargers, and reference voltage circuits. They are particularly useful for regulating voltages that may fluctuate due to variations in input voltage or load current. Compared to series regulators, shunt regulators have the advantage of being able to handle large input voltage variations and can provide a regulated output even when the input voltage drops below the desired output voltage. However, they are generally less efficient than series regulators because the excess current is dissipated as heat, which can be significant in high-power applications. The efficiency is directly related to the difference between the input and output voltages.