Tasavirtalähteen

Tasavirtalähteen is a Finnish term that translates to "constant current source" in English. It refers to an electronic device or circuit that is designed to deliver a specific, stable electric current to a load, regardless of variations in the load's resistance or the voltage supplied to the source. This is in contrast to a voltage source, which aims to maintain a constant voltage.

Constant current sources are crucial in applications where the current must be precisely controlled. For example, they are used in powering LEDs, as LEDs have a non-linear relationship between voltage and current, and slight voltage changes can cause significant current fluctuations, potentially leading to damage or inconsistent brightness. Other applications include charging batteries, driving certain types of sensors, and in precision measurement equipment.

The behavior of a tasavirtalähteen is characterized by its ability to adjust its output voltage dynamically to ensure the current remains at its set value. If the load resistance increases, the voltage across the load will rise to maintain the constant current. Conversely, if the load resistance decreases, the voltage will drop. This regulation is achieved through feedback mechanisms within the circuit, often involving transistors, operational amplifiers, or specialized integrated circuits. The ideal constant current source has infinite output impedance, meaning it acts as a perfect current regulator.