Equations. The current through the load at saturations is Ic= VP/Rc. The base current must be Ib= Ic/Beta. Transistors have a varying gain so we want to use the minimum beta value, to ensure saturation.
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How do you calculate BJT saturation?
Equations. The current through the load at saturations is Ic= VP/Rc. The base current must be Ib= Ic/Beta. Transistors have a varying gain so we want to use the minimum beta value, to ensure saturation.
How do you bias the BJT to operate at saturation region?
Either forward or reverse biasing is done to the emitter and collector junctions of the transistor….Transistor biasing.
| EMITTER JUNCTION | COLLECTOR JUNCTION | REGION OF OPERATION |
|---|---|---|
| Forward biased | Forward biased | Saturation region |
| Forward biased | Reverse biased | Active region |
What is the formula of saturation current?
Hint: We know that the current that flows in reverse bias PN junction diode is called reverse saturation current. From the diode current equation I=Is(eVηVT−1) the current should decrease as the temperature is increased but the opposite happens.
How is Ic sat calculated?
By Ohm’s law I=VR applied to RC:
- IC(SAT)=VCC−VCRC=25V−0.1V220Ω=24.9V220Ω=113mA.
- IB(SAT)=IC(SAT)β=113mA80=1.41mA.
- RB=VCC−VBIB(SAT)=25V−0.7V1.41mA=24.3V1.41mA=17.2kΩ
How do you calculate operating mode of BJT?
The operational mode of the BJT depends on how the junctions between the regions are biased. Since there are two junctions, the emitter-base junction (EBJ) and the collector-base junction (CBJ), and each of these junctions may be either forward- or reverse-biased, there are four possible modes of operation.
Which of the following is the formula for BJT active region?
Active Region – the transistor operates as an amplifier and Ic = β*Ib.
What is reverse saturation equation?
What is VI characteristic equation?
The current-voltage function (also called the “i-v characteristic”) for an ideal diode is. i(v)=IS[exp(vηVT)−1],v>VZ. where IS is the reverse saturation current, v is the applied voltage (reverse bias is negative), VT=T/11,586 is the volt equivalent of temperature, and.
How do you calculate saturation current in an inductor?
Power dissipation is given as the sum of the Irms current power calculated from the classic equation P = I2R and the AC ripple current for core loss. Saturation current, denoted as Isat, is defined as the amount of DC current to cause inductance drop. This is typically 5-35 % of its initial value.
What is reverse saturation current in BJT?
The reverse saturation current is the reverse current of an ideal pn junction and it is limited by diffusion of minority carrier from the neutral regions towards the space charge region.
Why it is called saturation region in BJT?
It’s just the region where the transistor is “saturated” with current, it’s the point at which the transistor will not allow more current to flow through Collector-Emitter junction no matter what load is connected.
How is BJT VCE calculated?
Calculate Vce using the formula Vce= Vcc – [Ie * (Rc + Re)]. Using the numbers from the previous examples, the equation works as follows: Vce = 12 – 0.00053 (3000 + 7000) = 12 – 5.3 = 6.7 volts.
What is the formula for IC?
IC = β IB , where β is a large number, typically greater than 100.
What are the four modes of operation in a BJT?
In cut of mode both of emitter to base and collector to base are reversed biased. In reverse bias condition, there is no current flow through the device, so there is no current flowing in the transistor….BJT modes of operation
- Cute of mode.
- Saturation mode.
- Active mode.
How do you find the mode of BJT?
To find out which mode a PNP transistor is in, reverse all of the < and > signs. For example, to put a PNP into saturation VC and VE must be higher than VB. You pull the base low to turn the PNP on, and make it higher than the collector and emitter to turn it off.
How do you find the transistor saturation region?
How to know if a Transistor is Saturated – Through Actual Testing. You can conclude the operation of a transistor if it is saturated or not by doing actual measurement. Monitor the collector-emitter voltage of your circuit with a DMM. If the reading is below 0.3V, the transistor is at saturation.