Advertisements
Advertisements
प्रश्न
Calculate the current through the circuit and the potential difference across the diode shown in figure. The drift current for the diode is 20 µA.
Advertisements
उत्तर
(a) From the circuit diagram, it can be said that the diode is reverse biassed, with applied voltage of 5.0 V.
Under reverse bias condition,
Current in the circuit = Drift current
So, the current in the circuit is 20 µA.
(b) Voltage across the diode will be equal to the voltage of the battery minus the voltage drop across the 20 ohm resistor.
\[\Rightarrow V = 5 - iR\]
\[ \Rightarrow V = 5 - (20 \times 20 \times {10}^{- 6} )\]
\[ \Rightarrow V = 5 - (4 \times {10}^{- 4} )\]
\[ \Rightarrow V = {10}^{- 4} (50000 - 4)\]
\[ \Rightarrow V = 49996 \times {10}^{- 4} \]
\[ \Rightarrow V = 4 . 9996 V \cong 5\] V
APPEARS IN
संबंधित प्रश्न
In an unbiased p-n junction, holes diffuse from the p-region to n-region because ______.
A zener diode is fabricated by heavily doping both p- and n- sides of the junction. Explain, why?
A student wants to use two p-n junction diodes to convert alternating current into direct current. Draw the labelled circuit diagram she would use and explain how it works.
Explain, with the help of a circuit diagram, the working of a photo-diode. Write briefly how it is used to detect the optical signals.
Mention the important considerations required while fabricating a p-n junction diode to be used as a Light Emitting Diode (LED). What should be the order of band gap of an LED if it is required to emit light in the visible range?
Draw a circuit diagram to study the input and output characteristics of an n-p-n transistor in its common emitter configuration. Draw the typical input and output characteristics.
The diffusion current in a p-n junction is
Diffusion current in a p-n junction is greater than the drift current in magnitude
Two identical p-n junction may be connected in series with a battery in three ways. The potential difference across the two p-n junctions are equal in
In a p-n junction with open ends,
(a) there is no systematic motion of charge carries
(b) holes and conduction electrons systematically go from the p-side to n-side and from the n-side to p-side respectively
(c) there is no net charge transfer between the two sides
(d) there is a constant electric field near the junction.
The potential barrier existing across an unbiased p-n junction is 0.2 volt. What minimum kinetic energy a hole should have to diffuse from the p-side to the n-side if (a) the junction is unbiased, (b) the junction is forward-biased at 0.1 volt and (c) the junction is reverse-biased at 0.1 volt?
In a p-n junction, a potential barrier of 250 meV exists across the junction. A hole with a kinetic energy of 300 meV approaches the junction. Find the kinetic energy of the hole when it crosses the junction if the hole approached the junction (a) from the p-side and (b) from the n-side.
When a p-n junction is reverse-biased, the current becomes almost constant at 25 µA. When it is forward-biased at 200 mV, a current of 75 µA is obtained. Find the magnitude of diffusion current when the diode is
(a) unbiased,
(b) reverse-biased at 200 mV and
(c) forward-biased at 200 mV.
The drift current in a p-n junction is 20.0 µA. Estimate the number of electrons crossing a cross section per second in the depletion region.
Consider a p-n junction diode having the characteristic \[i - i_0 ( e^{eV/kT} - 1) \text{ where } i_0 = 20\mu A\] . The diode is operated at T = 300 K . (a) Find the current through the diode when a voltage of 300 mV is applied across it in forward bias. (b) At what voltage does the current double?
Find the currents through the resistance in the circuits shown in figure.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
Draw the current-voltage characteristics for the device show in figure between the terminals A and B.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
When the base current in a transistor is changed from 30µA to 80µA, the collector current is changed from 1.0 mA to 3.5 mA. Find the current gain β.
During the formation of a p-n junction ______.
