Pn-junction under bias, Electrical Engineering

Assignment Help:

Q. pn-Junction under Bias?

Let an external source be connected between the p- and n-regions, as shown in Figure (a). (b) shows the circuit representation of the pn-junction or diode, and its external circuit. The voltage source V, called the bias, either decreases or increases the potential barrier, thereby controlling the flow of carriers across the junction. With V = 0, the barrier is unaffected and the pn-junction has zero current. Positive values of V, known as forward biasing, decrease the potential barrier, thereby increasing the number of electrons and holes diffusing across the junction. The increased diffusion results in a net current, called the forward current, from the p-tothe n-region. With increased V, the forward current further increases rapidly because the barrier is reduced even further.Making V negative (reverse biasing), on the other hand, increases the potential barrier and reduces the number of carriers diffusing across the boundary. The drift component produced by the electric field from the n-tothe p-region causes a small current, called the reverse current (or saturation current) IS. The magnitude of the saturation current depends on the doping levels in the p- and n-type materials and on the physical size of the junction. Increasing the reverse bias, however, does not affect the reverse current significantly until breakdown occurs.

1316_pn-Junction under Bias.png


Related Discussions:- Pn-junction under bias

Determine the type of the semiconductor, Determine the Type of the Semicond...

Determine the Type of the Semiconductor An unknown semiconductor has E g =1.1 eV and N t =N v . lt is doped with 10 16 /cm 3 donor atoms. - (a) Determine the type of the s

Describe what you understand by offset voltage, a. Describe what you unders...

a. Describe what you understand by 'offset voltage' and 'offset current' of op-amp.  Discuss with a neat circuit diagram the method used for minimizing offset voltage and offset cu

Define resistance in lumped-circuit, Q. Define Resistance in lumped-circuit...

Q. Define Resistance in lumped-circuit? An ideal resistor is a circuit element with the property that the current through it is linearly proportional to the potential differenc

Phenomenon - fet operation, Phenomenon - Fet operation: For either imp...

Phenomenon - Fet operation: For either improvement- or depletion-mode devices, at drain-to-source voltages very much less than gate-to-source voltages, changing the gate volta

Downsampling in dsp, #ques1. (MATLAB) Generate 100 samples of the signal ...

#ques1. (MATLAB) Generate 100 samples of the signal  = sin (0.125). We want to decimate this signal using D = 2. • Design a 25-order lowpass filter using the Parks-McClella

Define a voltmeter, Define a voltmeter A voltmeter is an instrument us...

Define a voltmeter A voltmeter is an instrument used to measure p.d. and must be linked in parallel with the part of the circuit whose p.d. is required.

Zener Diode, #question ...THE APPLICATION AND OPERATION OF ZENER DIODES

#question ...THE APPLICATION AND OPERATION OF ZENER DIODES

Rotating magnetic fields, When a machine has more than two poles, only a si...

When a machine has more than two poles, only a single pair of poles needs to be considered because the electric, magnetic, and mechanical conditions associated with every other pol

Explain light-emitting diode, Q. Explain Light-emitting diode? This is ...

Q. Explain Light-emitting diode? This is a reliable, rugged, and inexpensive semiconductor display device requiring about 10 mA of current flow for full illumination. An LED is

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd