# JFET Active-mode operation

Status
Not open for further replies.

#### Unregistered

Joined Dec 31, 1969
0
Because JFETs are voltage-controlled current regulators (at least when they're allowed to operate in their active), their inherent amplification factor cannot be expressed as a unitless ratio as with BJTs. In other words, there is no β ratio for a JFET. This is true for all voltage-controlled active devices, including other types of field-effect transistors and even electron tubes. There is, however, an expression of controlled (drain) current to controlling (gate-source) voltage, and it is called transconductance. Its unit is Siemens, the same unit for conductance (formerly known as the mho).

in their active...) region? conditions? mode?

#### hgmjr

Joined Jan 28, 2005
9,029