input impedance

Input impedance refers to how much a device resists or opposes an electrical signal when it's connected to it. Think of it like a gate that controls how much current can flow into a device; a high input impedance allows signals to pass with little resistance, preventing the device from drawing too much power or affecting the source. Conversely, low input impedance means more resistance, which can load down the signal source. This concept is important in ensuring accurate signal transfer and preventing distortion or power loss in electronic systems, especially in audio, communication, and measurement equipment.