Schottky Varactor Tunnel Zener. Schottky Diode: Its symbolic representation is as shown:- It is not a typical diode because it does not have a p-n junction.
This makes the Shottky diode useful for high-frequencies and digital applications. Schottky diode is also known as the Schottky barrier diode, surface barrier diode, majority carrier device, hot-electron diode, or hot carrier diode. Varactor Diode: It is represented by a symbol of diode terminated in the variable capacitor as shown below: Varactor diode refers to the variable Capacitor diode, which means the capacitance of the diode varies linearly with the applied voltage when it is reversed biased.
Tunnel diode : It is a highly doped PN Junction diode, used for low voltage high-frequency switching applications. It works on the tunneling principle. When compared to a normal p-n junction diode, tunnel diode has a narrow depletion width. Their low capacitance allows them to function at microwave frequencies.
Tunnel diodes are not good rectifiers, as they have relatively high leakage current when reverse biased. Zener Diode: The device used for the voltage regulator is a Zener diode.
It is used to regulate the voltage level. It generates a fixed output voltage that remains constant for any changes in load conditions or input voltage. Zener diode is a PN junction silicon PN junction diode that has a low specified reverse voltage which takes advantage of any reverse voltage applied to it.
It is unlike a normal diode Schottky diode, varactor diode, tunnel diode that blocks any flow of current through itself when reverse biased. From the I-V characteristics curve shown, the voltage across the diode in the breakdown region is almost constant. In the breakdown region , it is used in voltage regulator applications. A rectifier is a circuit that converts the AC signal at its input to pulsating DC at its output. Negative half wave rectifier clips the positive half of the input signal and only negative part of the input signal is present Download Solution PDF Share on Whatsapp.
Depletion region decreases Minority carries are not attected Holes and electrons move away from junction All of above. Concept: When a p-type semiconductor crystal is brought into close contact with an n-type semiconductor crystal, the resulting arrangement is called p-n junction diode. Explanation : Forward Bias — When the negative terminal of the battery is connected to N — side and the positive terminal to P —side , then the connection is called forward bias.
In forward biasing , the applied voltage V of the battery mostly drops across the depletion region and the voltage drops across the p-side and n-side of the p-n junction is negligibly small. It is because the resistance of the depletion region is very high as it has no free charge carriers. In forward biasing the forward voltage opposes the potential barrier V b.
As a result of it, the potential barrier height is reduced and the width of the depletion layer decreases. As forward voltage is increased, at a particular value the depletion region becomes very much narrow such that a large number of majority charge carriers can cross the junction. Crystal Oscillator : A crystal oscillator is the most stable frequency oscillator. Advantages : The crystal oscillator is possible to obtain a very high precise and stable frequency of oscillators It has very-low-frequency drift due to change in temperature and other parameters The Q is very high It has automatic amplitude control Disadvantages : These are suitable for high-frequency application Crystals of low fundamental frequencies are not easily available Hartley and Colpitts's oscillators are LC oscillators.
LC oscillators are unstable oscillators. Phase shift oscillator is suitable for oscillations in AF range up to 1 kHz Crystals like quartz have high-quality factors, Q range: 10 4 - 10 6.
The high-quality factor will result in high-frequency stability. Answer Detailed Solution Below Option 4 : Calculation: Given rectifier is a 3-phase Full-wave rectifier. It is a 6 pulse rectifier. Some important optical detector devices are: PIN diode P-type, intrinsic, n-type Avalanche photodiode APD Photomultiplier Tube PMT Phototransistor The advantage of the photomultiplier tube is its ability to measure relatively small amounts of electromagnetic radiation sensitivity because of the amplification process that occurs.
Comparison between optical detector: So, PMT can be used when very high sensitivity and bandwidth are required. Frequency Ripple Harmonics Amplitude. A capacitor is included in the rectifier circuit to act as a filter to reduce ripple voltage. The important property of the capacitor is that it passes the AC signal but blocks the DC signal and hence capacitor is used in the rectifier circuit. Super conductor Extrinsic semiconductor Insulator Intrinsic semiconductor. For example Silicon, Germanium, etc Intrinsic s emiconductors : Intrinsic semiconductors have equal numbers of electrons and holes.
Squirrel cage induction motor Wound rotor induction motor AC commutator motor Synchronous motor. Emitter junction is forward biased and collector junction is reverse biased Emitter junction is reverse biased and collector junction is forward biased Emitter junction junction is reverse biased and collector junction is reverse biased Emitter junction is forward biased and collector junction is forward biased.
Answer Detailed Solution Below Option 1 : Emitter junction is forward biased and collector junction is reverse biased. BJT's are current-driven devices i. It is a current-controlled device. The current through the two terminals is controlled by a current at the third terminal base.
It is a bipolar device current conduction by both types of carriers, i. Emitter junction is forward biased and collector junction is reverse biased BJT works as a variable resistance. Bonding agent Strong coupler Impedance regulator Insulator. Ceramics are hard and brittle and are in the form of amorphous or glassy solids. The bond in these materials is mixed ionic and covalent. The electrons are not free to move, hence they are thermal and electrical insulators.
At low temperatures, ceramics behave elastically. They do not possess any malleability. A ceramic is a solid material comprising an inorganic compound of metal, non-metal, or metalloid atoms primarily held in ionic and covalent bonds. Common examples are earthenware, porcelain, and brick. Ceramics have certain properties like High melting points so they are highly heat resistant.
Great hardness and strength. Very durable. Very low thermal conductivity. Very much inert to chemical activities so they are unreactive to other chemicals resulting in a longer lifespan.
Reverse cutoff Cutoff Saturation Forward active. Inductors are used to block AC while allowing DC to pass through it, inductors designed for this purpose are known as chokes. The inductor carries the property of opposing the change in current that flows through it. In other words, the inductor offers high impedance to the ripples and no impedance to the desired dc components.
Thus the ripple components will be eliminated. When the rectifier output current increases above a certain value, energy is stored in it in the form of a magnetic field and this energy is given up when the output current falls below the average value.
Work function is the maximum energy required by the fastest electron at 0 K to escape from the metal surface. A transistor has a current gain of 0. Its current gain in the CC mode is. Reason R : When a reverse bias is applied to p-n junction, the width of depletion layer increases. A is true but R is false D. A is false but R is true. An intrinsic silicon sample has 1 million free electrons at room temperature. As the temperature is increased.
What is the necessary a. For a NPN bipolar transistor, what is the main stream of current in the base region? Drift of holes B. Diffusion of holes C. Drift of electrons D. Diffusion of electrons. Which one of the following is not a characteristic of a ferroelectric material? High dielectric constant B. No hysteresis C. Ferroelectric characteristic only above the curie point D. Electric dipole moment. Which of the following could be the maximum current rating of junction diode by ?
When diodes are connected in series to increase voltage rating the peak inverse voltage per junction. Hall effect is observed in a specimen when it is carrying current and is placed in a magnetic field. The resultant electric field inside the specimen is. Silicon is not suitable for fabrication of light emitting diodes because it is. For a P-N diode, the number of minority carriers crossing the junction depends on.
Pure annealed copper B. Hard drawn copper C. Induction hardened copper D. Copper containing traces of silicon. The forbidden energy gap between the valence band and conduction band will be least in case of. Your email address will not be published. At room temperature the current in an intrinsic semiconductor is due to A.
True B. False Answer: B 3. The most commonly used semiconductor material is A. In which of these is reverse recovery time nearly zero? Zener diode B. Tunnel diode C. Schottky diode D. PIN diode Answer: C 5. Its current gain in the CC mode is A. The amount of photoelectric emission current depends on A. Assertion A : A p-n junction has high resistance in reverse direction. A is false but R is true Answer: A 8. Voltage series feedback Also called series-shunt feedback results in A.
How many free electrons does a p type semiconductor has?
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