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it converts it to a diode. sometimes this is done for matching the characteristics of diodes and transistors in the circuit. standard diodes might not have similar enough curves to the transistors for the circuit to operate correctly.
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Why is collector reverse biased?
to prevent direct conduction from base while collectingminority base carriers from emitter that "overshoot" the thin base.
What happens when the base current of a transistor is decrease?
in a properly biased transistor, collector and emitter current also decrease
What will happen if emitter base is reversed bias and collector base is forward bias?
If emitter-base is reverse biased then there will be no amplification effect on collector-emitter. If collector-base is forward biased, it will act like a diode, but without emitter-base current, that is meaningless.
How must the two transistor junction be biased proper transistor amplifier operation?
A: Actually it is only one transistor required for amplification the other junction can be a diode. As current Begin to flow it causes a bias across one junction which is opposite biasing for the other, A good differential amplifier will have those junction virtually at the same point with a very good current source because any mismatched will cause and output without any input. It is called voltage offset on the other end if the feedback current is very small it will also produce an output voltage offset known as current offset or basically errors
Why emitter base junction is always forward biased for normal operation of transistor?
The easy answer - it's not always forward biased. Both it, and the collector-base junction, must be forward biased to pass current through to the collector. Whether NPN or PNP the relative bias (voltage) on the base determines the conduction from emitter to collector. NPN: if the base is positive, relative to the collector and emmiter, the transistor conducts. PNP: if the base is negative, relative to the collector and emmitter, it conducts. For either transistor arrangement, draw two diodes connected either by their anodes or by their cathodes. The base is the region between them. In an NPN, a positive voltage on the anode, compared the to the cathode(s), will forward bias both, allowing current to flow. The same applies to a PNP with a relative negative voltage being the 'switch', turning both on. bob 02/07/2009 The first paragraph is incorrect. The collector-base junction will be reverse biased for normal operation. The only time an NPN base will be biased more positively than the collector is when it's operating in saturation mode. The second paragraph is also misleading. It implies that current flows (for NPN) from the collector to the base and then from the base to the emitter. Emitter current is base current plus collector current. The collector-base junction is normally reverse biased, so little current would flow. Here's a link with relevant info: http://www.nationmaster.com/encyclopedia/Bipolar-junction-transistors Dennis
Why collector base junction is always reverse biased for normal operation of transistors?
collector junction is reverse biased so as to remove the charge carriers away from its junction with the base.
How do you know if a transistor is a PNP or an NPN?
To know if a transistor is PNP or an NPN,the following should be verified:For a PNP transistor, the base-collector junction is forward biased while the base-emitter junction is reversed biased.For an NPN transistor, the base-emitter junction is forward biased while the base -collector junction is reversed biased.
How can electrons flow through base collector reversed biased region in transistors?
collector base is reverse biased (connect n region to be +ve terminal &p region to - ve terminal .due to forward biasing at emittor base juntion electrons follow from emittor to base .
Why is collector reverse biased?
to prevent direct conduction from base while collectingminority base carriers from emitter that "overshoot" the thin base.
Why is the collector of a transistor connected to the base or heatshink?
Because most of the heat buildup occurs in the reverse biased collector-base junction where Ic = Ie + Ib flows.
Stability factor for collector to base bias?
for a collector to base biased circuit find the stability factor s?what is the effect on s for change in current amplification factor?
A PNP transistor is connected in a circuit so that the collector-base junction remains reverse biased and the emitter-base junction is forward biased This transistor can be used as a power amplifier?
Yes1
What is transistor action?
The transistor has three regions, emitter,base and collector. The base is much thinner than the emitter while the collector is wider than both. However for the sake of convenience the emitter and collector are usually shown to be of equal size. The transistor has two pn junctions that means it is like two diodes. The junction between emitter and base may be called emitter-base diode or simply the emitter diode.The junction between base and collector may be called collector-base diode or simply collector diode. The emitter diode is always forward biased and the collector diode is always reverse biased.
What happens when the base current of a transistor is decrease?
in a properly biased transistor, collector and emitter current also decrease
What is the biasing technique in transistor for it to be in active region?
For a transistor to be in active region : Base Emitter junction should be forward biased and Emitter collector junction should be reverse biased.
What will happen if emitter base is reversed bias and collector base is forward bias?
If emitter-base is reverse biased then there will be no amplification effect on collector-emitter. If collector-base is forward biased, it will act like a diode, but without emitter-base current, that is meaningless.
How must the two transistor junction be biased proper transistor amplifier operation?
A: Actually it is only one transistor required for amplification the other junction can be a diode. As current Begin to flow it causes a bias across one junction which is opposite biasing for the other, A good differential amplifier will have those junction virtually at the same point with a very good current source because any mismatched will cause and output without any input. It is called voltage offset on the other end if the feedback current is very small it will also produce an output voltage offset known as current offset or basically errors
