0
In pn junction the depletion region capacitance increase with reverse bias or decrease?
Wiki User
∙ 15y ago
any capacitance is given by equation C = (epsilon * A/ d) where d is distance between two plates, thus as d reduces C increases. Now, in depletion region as we increase reverse bias, the depletion region width increases. Now consider depletion region as a parallel plate capacitor, with positive charges on n side and negative charges on p side. Thus, as reverse bias increases, d of junction capacitance increases thus capacitance reduces. On other hand, as reverse bias reduces, d of junction capacitance reduces, thus capacitance increases. -Amey Churi
Wiki User
∙ 15y ago
Add your answer:
Earn +20 pts
What is the relationship between capacitance and reverse bias voltage in an abrupt junction varactor diode?
Generally, the depletion region thickness is proportional to thehttp://www.answers.com/topic/square-root of the applied voltage; and http://www.answers.com/topic/capacitanceis inversely proportional to the depletion region thickness. Thus, the capacitance is inversely proportional to the square root of applied voltage.
Difference between Schottky Barrier Diodes and PN junction diodes?
Difference between Schottky Barrier Diode and P-N Junction Diode is as following...Schottky Diode1) Usually using the aluminum metal which is trivalent element. 2) Depletion layer is thinner than the p-n junction diode.3) Forward threshold voltage is smaller than p-n junction diode(0.1V).4) The junction capacitance is lower than p-n junction diode.P-N Junction Diode1) Trivalent impurity is added to the pure silicon structure. 2) Depletion layer is wider than Schottky diode.3) Forward threshold voltage is higher than Schottky diode(0.6V)4) The junction capacitance is higher than Schottky diode.
What is the type of capacitance effect exhibited in P-N junction when it is reverse biased?
1. Transition capacitance 2. Diffusion capacitance 3. Space charge capacitance 4. Drift capacitance
How do you control PN-junction?
When a pn junction is direct polarized, the height of the depletion layer is reduced and majority charge carriers now have sufficient energy to cross the junction and when it is revers polarized the height of the depletion layer is increased and the number of majority charge with sufficient energy to cross the junction is cut sharply.
What is pn junction capacitance?
The charge inside of a p-n diode with a connected voltage variety yields a capacitance is need to add circuit model of a p-n diode. The capacitance connected with the charge variety in the exhaustion layer is known as the intersection capacitance, in the same process capacitance connected with the abundance bearers in the semi impartial district is known as the dissemination capacitance.
Why is junction capacitance of collector to base junction is lower than base to emitter junction?
The collector base depletion zone is wider than the emitter base depletion zone.
What will happen to the depletion region when the P-N junction is supplied by forward bias?
depletion region will decrease.
Which junction has least junction capacitance?
point contact has the least junction capacitance
Why a pn junction posses capacitance?
depletion region acts as dielectric between conducting p-plate and n-plate. Note: junction must be in non-conducting state.
What is meant by transistion and space charge capacitance of a diode?
Diffusion capacitance is the capacitance due to transport of charge carriers between two terminals of a device. - Amog This diffusion capacitance is due to depletion capacitance which is a function of forward bias applied to emitter junction of a transistor and due to diffusion capacitance which a function of transconductance of the transistor. Its value is 100 pF. Tirupanyam B.V
What is the difference between diffusion capacitance and transition capacitance?
Transition capacitance : A reverse biased PN-junction has a region of high resistivity (depletion layer) sandwiched in between two regions of relatively low resistivity. The P-N regions act as the plates of a capacitor and the depletion layer acts as the dielectric This is known as the transition capacitance or depletion capacitance. Diffusion capacitance : It is the capacitance due to transport of charge carriers between two terminals of a device like the forward biased PN junction. In a semiconductor device with a current flowing through it (for example, an ongoing transport of charge by diffusion) at a particular moment there is necessarily some charge in the process of transit through the device. If the applied voltage changes to a different value and the current changes to a different value, a different amount of charge will be in transit in the new circumstances. The change in the amount of transiting charge divided by the change in the voltage causing it is the diffusion capacitance. The adjective "diffusion" is used because the original use of this term was for junction http://www.answers.com/topic/diode, where the charge transport was via the diffusion mechanism.
Are junction capacitance and transition capacitance the same?
Junction capacitance is used to take the ripple out of DC circuits primarily. The other is used in voltage doublers or step ups as a storage.
What is the relationship between capacitance and reverse bias voltage in an abrupt junction varactor diode?
Generally, the depletion region thickness is proportional to thehttp://www.answers.com/topic/square-root of the applied voltage; and http://www.answers.com/topic/capacitanceis inversely proportional to the depletion region thickness. Thus, the capacitance is inversely proportional to the square root of applied voltage.
Is it true or false and why 1-There are no effect for transition capacitance under forward bias 2- For CE configuration if outport voltage increase the input current will be decrease?
Q1: A PN juncrion has to be reverse-biased for a transiton capacitance to exist. In forward bias there is no depletion layer and the junction conducts, so it does not behave as a capacitance. Q2: In a common-emitter circuit the ouput voltage appears across a resistor connected between the collector and the positive rail (for a normal NPN transistor). Therefore when the current through the transistor increases, there is more voltage drop across this resistor and the collector voltage has to fall.
Difference between Schottky Barrier Diodes and PN junction diodes?
Difference between Schottky Barrier Diode and P-N Junction Diode is as following...Schottky Diode1) Usually using the aluminum metal which is trivalent element. 2) Depletion layer is thinner than the p-n junction diode.3) Forward threshold voltage is smaller than p-n junction diode(0.1V).4) The junction capacitance is lower than p-n junction diode.P-N Junction Diode1) Trivalent impurity is added to the pure silicon structure. 2) Depletion layer is wider than Schottky diode.3) Forward threshold voltage is higher than Schottky diode(0.6V)4) The junction capacitance is higher than Schottky diode.
What is the main drawback of thyristor?
thyristor is four layer three junction device,hence there is effect of the junction capacitance on the operation.thyristor also requires special techniques to make it on and off.along with this the delays produced due to junction capacitance has to be considered.
What is the type of capacitance effect exhibited in P-N junction when it is reverse biased?
1. Transition capacitance 2. Diffusion capacitance 3. Space charge capacitance 4. Drift capacitance
