väljundtakistuse

Väljundtakistus, often translated as output impedance or output resistance, is a fundamental parameter in electronics that describes the resistance of an electrical source or component to the flow of current when a voltage is applied. It is a key characteristic of active electronic components like amplifiers, transistors, and signal generators, as well as passive components like resistors.

In simple terms, output impedance represents the internal resistance of a voltage source. When a load is connected to a source, a portion of the generated voltage is dropped across the output impedance. This means that the voltage delivered to the load will be less than the source's open-circuit voltage, especially if the load resistance is comparable to or smaller than the output impedance. The relationship is governed by Ohm's Law and the voltage divider principle.

A low output impedance is generally desirable for voltage sources. This is because it minimizes voltage loss across the source itself, allowing more of the generated voltage to be delivered to the load. This leads to better power transfer and signal integrity, especially when driving loads with varying or low impedances. Conversely, a high output impedance can limit the current delivered to the load and cause significant voltage drops.

In contrast, for current sources, the concept of output impedance is analogous but refers to the source's resistance to variations in voltage. A high output impedance is typically desired for current sources to maintain a stable current output regardless of the load resistance. Understanding and managing output impedance is crucial for designing efficient and well-performing electronic circuits, ensuring proper signal transfer, and avoiding signal degradation.