Load Impedance

A load or load impedance is the concept of connecting a device or component to the output of a functional block, thus drawing from it a measurable amount of current. For example, you can connect a resistor to a power supply or connect a buffer (op-amplifier) amplifier to an oscillator. Therefore, a load impedance is the input impedance of the next functional block in the chain.

A load impedance is present when the load has components other than just purely resistive components, like resistors, and also incorporates reactive components like inductors and capacitors. The reactive components represent the imaginary impedance, whereas the resistive elements contain real impedance.

Load impedance affects the performance of circuits, more specifically, output voltages and currents. These effects occur in voltage sources, sensors, and amplifiers, to name a few.