What is saturation and cutoff in transistor?
Saturation — The transistor acts like a short circuit. Current freely flows from collector to emitter. Cut-off — The transistor acts like an open circuit. No current flows from collector to emitter. Active — The current from collector to emitter is proportional to the current flowing into the base.
What is the condition for cut-off region?
The transistor operates in cutoff region when both the emitter and collector junctions are reverse biased. As in cutoff region, the collector current, emitter current and base currents are nil, we can write as. IC=IE=IB=0.
What is cutoff region MOSFET?
When the input voltage, ( VIN ) to the gate of the transistor is zero, the MOSFET conducts virtually no current and the output voltage ( VOUT ) is equal to the supply voltage VDD. So the MOSFET is “OFF” operating within its “cut-off” region.
What is the cutoff region of a transistor?
When load line intersect IB = 0, it is known as cut off region of the transistor. As the base current is zero, only small collector leakage current flows. The base emitter junction does not remain in the forward biased because the base current is zero. The collector to emitter voltage is equal to VCC.
What is the difference between cut-off and saturation?
In cut off region, both emitter to base and base to collector junction is in the reverse bias and no current flows through the transistor. The transistor acts as an open switch. In the saturation region, both the junctions are in forwarding bias,and the transistor acts as a closed switch.
What is active region saturation region and cutoff region?
a)When both collector-base & base-emitter junction is reverse biased, it is the active region. b)When both collector-base & base-emitter junction is forward biased, it is the saturation region.
What is the condition of cut-off region VGS?
Cut-off region: When VGS < Vt, no channel is induced and the MOSFET will be in cut-off region. No current flows. Triode region: When VGS ≥ Vt, a channel will be induced and current starts flowing if VDS > 0. MOSFET will be in triode region as long as VDS < VGS – Vt.
What is saturation in MOSFET?
First of all, “saturation” in mosfets means that change in VDS will not produce significant change in the Id (drain current). You can think about MOSFET in saturation as a current source. That is regardless of the voltage across VDS (with limits of course) the current through the device will be (almost) constant.
Why does MOSFET go into saturation?
for a BJT, saturation means that the transistor does NOT determine the collector current Ic. This happens when Vcethe transistor DOES determine the drain current Id. This happens when Vds>Vds,sat.
What is cutoff current?
What It Is: Collector cutoff current is the IC that still flows when the specified VC and a specified reverse bias is applied. It is normally less than either ICEO or ICER (collector current with the base open, or with the base resistively connected to the emitter).
What do you mean by cut-off in basic electronics?
In electronics, cut-off is a state of negligible conduction that is a property of several types of electronic components when a control parameter (that usually is a well-defined voltage or electric current, but could also be an incident light intensity or a magnetic field), is lowered or increased past a value (the …
Is the cut off region linear or nonlinear?
So it is linear. In Cut off region, Response is : Ic = F (Vce) = 0. – No matter how large the increase in Vce, Ic is still zero. It is Similar to Air gap. So it should be linear as well.
How to find the slope of a curve in saturation region?
In Saturation region, Response is : Ic = const * Vce. With const being the slope of the curve. In reasonable Vce, I see this slope is of a straight line (not of a power function).
What is the effect of saturation on collector current?
At saturation, collector-base junction no longer remains reverse biased and normal transistor action is lost. If base current is greater than IB ( sat ), then collector current cannot increase because collector-base junction is no longer reverse-biased. (iii) Active region. The region between cut off and saturation is known as active region.
What is the saturation point of a circuit?
The point where the load line intersects the IB = IB ( sat) curve is called saturation. At this point, the base current is maximum and so is the collector current.