TRANSISTOR SATURATION MODE FREE

Note that in the depletion region there are no free electric carriers and the area acts as a dielectric.

The reason I am asking this is, in saturation region the collector base junction which is forward biased should repel all the charge carriers from the emitter. Figure 2.7: The nMOS transistor operating in the saturation mode PINCH-OFF POINT In the saturation mode, the depletion region adjacent to the drain is enlarged. How come this can happen ? How come transistor allows maximum current in the saturation region. When Vce reaches Vce(sat) maximum current is passing through the collector. In accumulation mode the capacitance is just due to the voltage drop across tox In inversion the incremental charge comes from the inversion layer (depletion region stops growing).

So its fair.īut my question is that it is not happening in the ce configuration as Vcb<0 ) then collector current is starting to decrease. (in this section Si NPN BJT transistor at 3000K parameters are used ). So as the cb junction is starting to become forward biased (i.e. saturation region, cutoff region and active mode/region, bias. Let us now see CB configuration output characteristics of a npn transistorĪs we can see sir if we decrease the voltage Vcb below zero we know that collector base junction will start to become forward biased (if it reaches 0.7v then it will become CB junction will become forward biased ). in this case the collector base barrier voltage would be overcome and charge carriers from the emitter would be repelled from the collector base junction “ and due to some things which were explained later in the book it doesnot happen so some collector current will flow so the voltage will Vce(sat)=0.2V this means the collector current should decrease as cb becomes forward biased “if Vce went down to exactly zero volts, the collector base junction would become forward biased by 0.7v.

Yesterday I was reading a book named electronic devices and circuits by david a bell. Lets now divert our attention towards the working of the transistor in the saturation region Whatever may be the configuration (ce cb or cc)īase emitter junction is forward biased and collector base junction is reverse biased

Transistor saturation mode