1. Describe an intrinsic semiconductor material. What is meant by the intrinsic carrier concentration? An intrinsic semiconductor is a single-crystal semiconductor material with no other types of

1. Describe an intrinsic semiconductor material. What is meant by the intrinsic carrier concentration? An intrinsic semiconductor is a single-crystal semiconductor material with no other types of atoms within the crystal. In an intrinsic semiconductor, the densities of electrons and holes are equal, since the thermally generated electrons and holes are the only source of such particles.

2. Describe the concept of an electron and a hole as charge carriers in the semiconductor material. Current is often schematized as being carried either by the flow of electrons or by the flow of positively charged "holes" in the electron structure of the material.

3. Describe an extrinsic semiconductor material. What is the electron concentration in terms of the donor impurity concentration? What is the hole concentration in terms of the acceptor impurity concentration? An extrinsic semiconductor is a semiconductor that has been doped, that is, into which a doping agent has been introduced, giving it different electrical properties than the intrinsic (pure) semiconductor. N-type semiconductors are created by doping an intrinsic semiconductor with donor impurities. In an n-type semiconductor, the Fermi energy level is greater than that of the intrinsic semiconductor and lies closer to the conduction band than the valence band./// P-type semiconductors have Fermi energy levels below the intrinsic Fermi energy level. The Fermi energy level lies closer to the valence band than the conduction band in a p-type semiconductor

4. How is a pn junction formed? What is meant by a built-in potential barrier, and how is it formed? A p–n junction is formed at the boundary between a p-type and n-type semiconductor This built-in potential keeps the majority of holes in the p-region, and the electrons in the n-region. It provides a potential barrier, which prevents current flow across the junction.

5. Explain the principle of working of p-n-junction at forward voltage.

6. Explain the principle of working of p-n-junction at reverse voltage

7. Write the ideal diode current–voltage relationship. Describe the meaning of IS and VT. V _T is the thermal voltage I _S is the reverse bias saturation current

8. Describe the iteration method of analysis and when it must be used to analyze a diode circuit./using trial and error to find a solution to a problem.

9. Describe the piecewise linear model of a diode and why it is useful. What is the diode turn-on voltage? This method models the diode with segments of straight lines to approximate the diode’s current–voltage characteristics, using linear relationships/

10. Define a load line in a simple diode circuit

11. Other diode types: solar cell, photodiode, light-emitting diode, Schottky barrier diode. A solar cell is a p-n junction device with no voltage directly applied across the junction. When light hits the space-charge region, electrons and holes are generated. They are quickly separated and swept out of the space charge region by the electric field, thus creating a photocurrent.// Photodetectors are devices that convert optical signals into electrical signals. An example is the photodiode, which is similar to a solar cell except that the p-n junction is operated with a reverse-bias voltage.// The light-emitting diode (LED) converts current to light// A Schottky barrier diode, or simply a Schottky diode, is formed when a metal, such as aluminum, is brought into contact with a moderately doped n-type semiconductor to form a rectifying junction.

12. Describe a simple half-wave diode rectifier circuit and sketch the output voltage versus time. Since the output voltage appears onlyduring the positive cycle of the input signal, the circuit is called a half-wave rectifier.

13. Describe a simple full-wave diode rectifier circuit and sketch the output voltage versus time.

14. Define ripple voltage. How can the magnitude of the ripple voltage be reduced? The alternating component of the unidirectional voltage from a rectifier or generator used as a source of direct-current power You reduce ripple voltage by adding a low-pass filter In the simplest case, you put a capacitor after the rectifier.

15. Describe a simple Zener diode voltage reference circuit

16. at effect does the Zener diode resistance have on the voltage reference circuit operation? Define load regulation

17. Describe the basic structure and operation of npn and pnp bipolar transistors// A bipolar junction) transistor (BJT) is a three-terminal electronic device constructed of doped semiconductor material and may be used in amplifying or switching applications. Bipolar transistors are so named because their operation involves both electrons and holes.// A small current entering the base is amplified to produce a large collector and emitter current. That is, when there is a positive potential difference measured from the emitter of an NPN transistor to its base (i.e., when the base is high relative to the emitter) as well as positive potential difference measured from the base to the collector, the transistor becomes active. In this "on" state, current flows between the collector and emitter of the transistor.// A small current leaving the base is amplified in the collector output. That is, a PNP transistor is "on" when its base is pulled low relative to the emitter. Transistor (from eng. transfer — переносить and resistance — сопротивление) is electronic device from semiconductor material, usually has three outputs, allowing outputs signal to manage the current in electrical circuit.

18. What are the bias voltages that need to be applied to an npn bipolar transistor such that the transistor is biased in the forward-active mode?

19. Define the conditions for cutoff, forward-active mode, and saturation mode for a pnp bipolar transistor.

20. Define common-base current gain and common-emitter current gain

21. Discuss the difference between the ac and dc common-emitter current gains

22. State the relationships between collector, emitter, and base currents in a bipolar transistor biased in the forward-active mode.

23. Define Early voltage and collector output resistance he Early effect is the variation in the width of the base in a bipolar junction transistor (BJT) due to a variation in the applied base-to-collector voltage. The Early voltage,V _A, an indicator of the extent of base widthmodulation, can be obtained by extrapolation of the output characteristics.

24. Describe a simple common-emitter circuit with an npn bipolar transistor and discuss the relation between collector–emitter voltage and input base current.

25. Describe the parameters that define a load line. Define Q-point

26. What are the steps used to analyze the dc response of a bipolar transistor circuit

кароче весь смысле в common-emitter current gain - это то что на базу, и на коллектор ты подаешь определенное напряжение, и получаешь определенный ток на эмитеере,

смысл common-base current gain - это то что на эмиттер, и на коллектор ты подаешь определенное напряжение, и получаешь определенный ток на базе

смысл common-collector current gain - это то что на базу, и на эмиттер ты подаешь определенное напряжение, и получаешь определенный ток на коллекторе это просто 3 разных подключения транзистора, кпц черт взяли упустили основной смысл транзистора -

напряжение на двух концах регуирует ток на 3-ем....фак ееее

Emitter is the electrode, emitting the charge carriers.

Collector receives the charge carriers, going from emitter.

Base is connected to the middle layer with different type of conductivity, managing the carriers flow.

Therefore the electron-hole junction emitter-base called emitter junction, and collector-base – collector junction

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