What is cutting voltage of germanium diode?
The cut in voltage for germanium diode is 0.25V. (for silicon-diode the cut in voltage is 0.65V).
What is the cut in voltage of silicon diode?
approximately 0.7 volts
What happens if a diode is shorted?
When the diode fails shorted the voltage drop will be very low. There will still be some voltage drop due to internal resistance. However in some circuits the current will rise to a very high level and then the diode will burn open from high power dissipation.
Which is the reverse biased diode?
In a circuit in option A, N junction is connected comparatively higher voltage than P junction. Hence diode in option A is reverse biased.
Where is Zener diode used?
Zener diodes are widely used in electronic equipment of all kinds and are one of the basic building blocks of electronic circuits. They are used to generate low-power stabilized supply rails from a higher voltage and to provide reference voltages for circuits, especially stabilized power supplies.
What is a reverse bias?
reverse bias The applied d.c. voltage that prevents or greatly reduces current flow in a diode, transistor, etc. For example, a negligible current will flow through a diode when its cathode is made more positive than its anode; the diode is then said to be reverse biased.
What happens when PN junction is reverse biased?
When a p-n junction is reversed biased, the negative terminal of the battery attracts the free holes in the p-type towards itself whereas the positive terminal attracts the free electrons in n-type towards itself.
Why current is constant in reverse bias?
If these electrons and holes are generated in the vicinity of junction then there is a flow of current. Since this current is due to minority carriers and these number of minority carriers are fixed at a given temperature therefore, the current is almost constant known as reverse saturation current ICO.
What causes the depletion region?
The depletion region is caused by the diffusion of charges. The holes and the electrons diffusing towards each other combine near the junction. In doing so positive and negative ions are formed. The pair of positive and negative ions at the junction forms the dipole.
Why there is no current in reverse bias condition?
In reverse bias condition, the charge carriers are pulled away from the p-n junction; as a result, the width of the p-n junction gets wider. The wider depletion region presents a greater obstacle to the charge carriers to pass through, as a result, very little current flows.
Does current flow in reverse bias justify?
In a standard diode, forward biasing occurs when the voltage across a diode permits the natural flow of current, whereas reverse biasing denotes a voltage across the diode in the opposite direction. However, the voltage present across a diode during reverse biasing does not produce any significant flow of current.
Why pn junction is not reverse biased?
In the reverse bias the voltage increases in the reverse direction across the p-n junction, but no current due to the majority carriers, only a minimal leakage current flows. But at a certain reverse voltage p-n junction breaks in conduction. It is only due to the minority carriers.
Which carriers are responsible for the reverse current flow?
The reverse saturation current caused in a p-n junction diode is caused by minority carriers. The rupture of covalent bonds create the minority carriers in the material and it solely depends on the temperature of the material.
What is the order of reverse current in a reverse biased pn junction?
(1) Ampere.
How reverse current is produced?
When a semiconductor device is reverse biased it should not conduct any current, however, due to an increased barrier potential, the free electrons on the p side are dragged to the battery’s positive terminal, while holes on the n side are dragged to the battery’s negative terminal.
What is the order of reverse saturation current?
The reverse saturation current is the order of micro-ampere (μA) .