Ledningsläge

Ledningsläge is a term used in electronics to describe the state in which an electrical component conducts current. It refers to the operating mode in which a device allows current to flow through its terminals, as opposed to when it blocks current or is non-conductive. The concept is relevant for various components, including diodes, transistors, thyristors, and switches, and it is determined by biasing, control signals, and the device’s intrinsic characteristics.

In diodes, for example, forward bias puts the diode in ledningsläge where current can pass, while reverse bias keeps it in non-conducting mode. For transistors, there is a conduction mode in which the collector-emitter path carries current; depending on the transistor type and region (bipolar transistor: active or saturation; MOSFET: on-state versus off-state), the extent of conduction changes and affects amplification and switching behavior. For relays and mechanical switches, closing the switch or energizing the coil places the device in ledningsläge, allowing current to flow to the load.

The term is used in circuit design, datasheets, and testing to describe when a component is actively passing current as part of normal operation or a specific function. Understanding ledningsläge helps predict voltage drops, power loss, and switching characteristics in electronic systems.