Quick Answer: How Do You Know If A Transistor Is Saturated?

How do I find my IC?

How to Calculate the Collector Current, Ic, of a TransistorUsing Known Values.Example.

If Ib=35μa and β=100, then Ic calculates out to be:Using Known Values.Example.

If Ie=4ma and β=150, then the value of Ic is computed to be:Using Known Values.

If base current, Ib, and emitter current, Ie, are known, then Ic can be calculated by the formula:Example..

Can a transistor be used as an amplifier?

A transistor acts as an amplifier by raising the strength of a weak signal. The DC bias voltage applied to the emitter base junction, makes it remain in forward biased condition. … Thus a small input voltage results in a large output voltage, which shows that the transistor works as an amplifier.

Why VCE SAT is 0.2 V?

Because the charge carriers injected from the base effectively eliminate the depletion zone between the collector and emitter. The collector current doesn’t have to overcome the P-N junction potential because the base current has neutralized it.

What do you mean by saturation?

saturation. Saturation means holding as much moisture as possible. When you water your houseplants, you may soak them until the soil around each plant reaches saturation. The noun saturation means the act of completely soaking something until it’s absorbed as much water as it can.

Why is Collector always reverse biased?

Collector is always reverse-biased w.r.t base so as to remove the charge carriers from the base-collector junction.

What is saturation voltage?

saturation voltage, collector-emitter (VCE(sat)) The voltage between the collector and emitter terminals under conditions of base current or base-emitter voltage beyond which the collector current remains essentially constant as the base current or voltage is increased.

How do you calculate IC saturation?

Therefore Ic= a*Ie and Ic= B*Ib. Therefore Ic(saturation)<=aIe and Ic(saturation)<=BIb. And the corresponding saturation voltages are, Vbe(sat)= 0.8 volts, Vce(sat)= 0.2 volts, Vcb(sat)= -0.6 volts.

What is saturation point in transistor?

Saturation is the fully conducting state in a semiconductor junction. The term is used especially in applications involving diodes and bipolar transistor s. As the forward bias in a semiconductor P-N junction increases, the current through the junction also increases, up to a certain point.

What is a saturation effect?

Saturation Effect. the decrease in the intensity of a spectral line (an absorption or emission line) with increasing power of the external resonant electromagnetic radiation.

What is hard saturation?

Hard saturation is when the transistor operates in the saturation region under all operating conditions. Remember that the current gain changes as the operating conditions such as temperature, and collector current, change.

Why is VBE 0.7 V?

For an unbiased transistor, considering only the BE junction which is a pn junction diode, 0.7V is the potential barrier. In an npn transistor base is positive(p) and emitter is negative(n). … But in a pnp transistor the base is negative(n) and emitter is positive(p) so the vbe=-0.7V.

What happens when a transistor is saturated?

A transistor in saturation mode acts like a short circuit between collector and emitter. In saturation mode both of the “diodes” in the transistor are forward biased. … Because the junction from base to emitter looks just like a diode, in reality, VBE must be greater than a threshold voltage to enter saturation.

Is VBE always 0.7 V?

VBE is the voltage that falls between the base and emitter of a bipolar junction transistor. VBE is approximately 0.7V for a silicon transistor. For a germanium transistor (which is more rare), VBE is approximately 0.3V. Again, this formula, can be used for either silicon or germanium transistors.

What is the saturation voltage of a transistor?

“Saturation” in a transistor switch circuit is achieved when the voltage across the collector/ emitter (VCE(sat)) is less than or equal to . 1 to . 3 volts – depending on the type of transistor. At that voltage point, the transistor appears to act like a simple SPST mechanical switch that has been closed (On).

Why is emitter always forward biased?

When the base emitter junction is forward biased and the collector/base junction is reverse biased, the electrons move from the n-type region towards the p-type region and the holes move towards the n-type region. When they reach each other they combine enabling a current to flow across the junction.

How is a transistor driven into saturation?

A transistor goes into saturation when both the base-emitter and base-collector junctions are forward biased, basically. So if the collector voltage drops below the base voltage, and the emitter voltage is below the base voltage, then the transistor is in saturation. Consider this Common Emitter Amplifier circuit.

Which transistor is best for switching?

Best Transistors: BJTs#1 NPN – 2N3904. You can find most often NPN Transistors in low-side switch circuits. … #2 PNP – 2N3906. For high-side switch circuits, you need a PNP style BJT. … #3 Power – TIP120. … #4 N-Channel (Logic Level) – FQP30N06L.

What is NPN and PNP transistor?

In an NPN transistor, a positive voltage is given to the collector terminal to produce a current flow from the collector to the emitter. In a PNP transistor, a positive voltage is given to the emitter terminal to produce current flow from the emitter to collector.