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When the both junction of NPN diode is reverse biased then the diode is mode?
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∙ 12y ago
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∙ 12y ago
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When both junction of npn diode reverse biased the the diode in what state?
reverse biased
When the both junction of npn diode is reverse biased then the diode in which mode?
Transistor will be in OFF mode.
When both junctions of npn diode are reverse biased?
When p-n junction of a diode reversed biased then majority carriers are not able to cross the junction and are attracted in respective regions.So current becomes approximately zero.But because of minority carriers a reverse current keeps flowing.It is called Reverse Saturation Current.And due to attraction towards sides,charges go away from junction.So width of depletion reason increases.
When both junctions of NPN diode are reverse biased then the diode is in which mode?
Transistor will be in OFF mode.
When both junctions of NPN diode are reverse biased then diode is in which mode?
Transistor will be in OFF mode.
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 if a semiconductor diode is being tested using a digital multimeter and the resistance of the diode is 10 ohms in both forward and reverse-biased conditions is the diode shorted or opened?
The diode is neither shorted nor open. It is a zener diode and it is conducting in both directions. If it were truly shorted, it would read closer to zero ohms in both directions.
What is meant by reverse saturation current?
reverse saturation current is produced by the thermal activity of the diode materials. This current: 1- Is temprature dependant; that is, it increases as temprature. 2- Accounts fot the major portion of diode reverse current surface leakage current is produced by contamination on the surface of the device, allowing current flow to bypass the junction
Formula for peak inverse voltage?
piv:the maximum value of reverse voltage across a diode that occurs at the peak of the input cycle when the diode is reversed-biased.
Is it necessary to add a series resistance with the diode or not?
if the diode is forward biasedwell practically the current flows in a circuit if and only if an effective resistance is present in the circuit, if we consider the diode to be ideal (barrier potential but no internal resistance) in this case an external resistance is required if we use the approximate model (both barrier potential and internal resistance are considered) we need not use an external resistance the internal resistance itself acts as the effective resistance.if the diode is reverse biased:-the same explanation applies even if the diode is reverse biased but one must take care that the reverse voltage drop on diode should not increase the peak inverse voltage mark the diode would be burnt or damaged if this phenomena occurs.So this can be prevented by adding suitable resistance to the circuit through which the voltage drop on diode can be managed
Why is current not zero in reverse biased semiconductors?
This is a lengthy answer. I tried to cover all the bases b/c I'm not sure how much you already know about semiconductors.Background:A semiconductor junction, such as that in a diode, is a connection between an N-type material and an P-type material. The N-type material has extra electrons and the P-type material has extra "holes," or a lack of electrons. Where the two materials meet, an area with neutral charge called a depletion region forms.In a forward-biased diode, electrons trying to travel from N to P have no problem because of the abundance of extra electrons in the N-type material. The same thing happens to the positive charge carriers (holes) in the P-type material. The depletion region (.7 volts wide in a silicon diode) collapses and electrons exchange with holes through the junction -> A current flows.In a reverse-biased diode, the depletion region (an insulator) actually grows because the unlike charges presented to each side of the junction pull the charge carriers (both electrons and holes) further away from the junction in the center. This prevents most of the current from flowing through the region.Answer:Because semiconductor technology is not perfect, a few charge carriers exist where they shouldn't. some electrons exist in the P-type material and some holes exist in the N-type material. These "minority carriers" are able to move through the depletion region of a reverse biased diode, and allow a small current to flow.Adding heat or exposing the junction to light will increase the number of minority carriers, and so more reverse-bias current will flow. This is actually useful information- for instance, by measuring the reverse current through a photodiode, you can determine how much light is hitting the junction and use this to create an optical receiver or light sensor.Keep your diodes cool,anp
Is zener diode a linear device?
Zener diode is not a linear device... it is non-linear one. Since linear devices are those devices which have linear characteristics(V-I CHAR.), or follows the Ohm's law i.e. voltage is directly proportional to current. but in case of Zener diode ohm's law fails down. the V-I char. in both forward biased & reverse biased condition is non-linear. So. Zener diode is non-linear device
