transkonductancë

Transkonduktancë, sometimes spelled transconductance, is a fundamental parameter in the characterization of electronic devices, particularly transistors and vacuum tubes. It represents the ratio of the change in output current to the change in input voltage. Mathematically, it is often denoted by the symbol Gm and is defined as Gm = ΔIo / ΔVi, where ΔIo is the change in output current and ΔVi is the change in input voltage, while other relevant voltages are held constant.

The unit of transconductance in the International System of Units (SI) is Siemens (S), which is equivalent to amperes per volt (A/V). A higher transconductance value indicates that a small change in input voltage will result in a larger change in output current, signifying a more sensitive device. This parameter is crucial for understanding amplifier gain and the overall performance of active electronic components. For a bipolar junction transistor (BJT), transconductance is primarily dependent on the collector current and temperature. For a field-effect transistor (FET), it is related to the drain current and gate-source voltage. Transconductance is an AC parameter, meaning it describes the device's behavior under varying signal conditions rather than its DC operating point.