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Why diode dose not allow to set voltage more than 0.7volts across it?
The barrier potential of the silicon diode is 0.7v if the applied voltage across it is more than this voltage then PN-junction of the diode breaks, once pn-junction breaks the voltage across the diode is constant, since it breaks at 0.7 this voltage will be constant and not exceed for any further increase in applied voltage -inform.mayaprasad@gmail.com The voltage across junction will only exceed from 0.7 volt (for silicon diode) in the case of reverse biasing the applied total voltage will appear across p-n junction. ANSWER: .7 VOLTS is an arbitrarily chosen number since a diode any diode have an exponential curve V vs I . This number is chosen when using a diodes but there are times when a greater or lesser voltage is chosen to reflect the application and the current trough the diode determine that. Example a diode gate diode will be chosen as .6 volts rather then .7v and a heavy conducting rectifier may have .8 volt to reflect closely the true value of the diode drop during real conditions
Define rms reverse voltage of a diode?
A DIODE will breakdown at a certain reverse voltage if RMS VOLTAGE IS SPECIFIED THEN the actual voltage will be RMS volts times 1.41
What is the PIV rating of diode?
A diode will provide saturating current if it reaches its Piv. What it should be well at least 1.5 of the applied reverse voltage. For AC at least 2 times to insure that the peak REVERSE voltage is blocked
What is purpose of diode in solenoid?
If the coil is powered with DC voltage, an inductive voltage is created anytime power to the coil is de-energized. The inductive voltage is called an inductive kick and it is up to ten times the applied voltage and is in reverse polarity to the applied voltage. A diode or other type of suppression device must be connected across the coil of the solenoid to protect any other electronic components in the circuit that may be damaged by this voltage. The diode is connected in reverse bias across the DC solenoid coil so that when voltage is applied in normal polarity, the diode does not provide a path for current. When the solenoid coil is de-energized, the inductive voltage is the opposite polarity to the power supply, so it will flow through the diode and back into the coil. Since the coil is made of a large length of wire. the energy of the inductive voltage will be dissipated as it moves through the wire. This will render the excessive inductive voltage harmless. The fact that the inductive voltage will travel through the diode in the forward bias direction means the 0.7-1 volt drop across the diode junction will also limit the V=< (dv/dt) surge. Fig. 4 (below) illustrates an example of the diode connected across the coil of a solenoid that is powered with DC voltage.
What is Transistor Switching time?
Transistor switching times: The turn-on time of switching transistor sum of delay time (td) and rise time (tr). ton = td + tr. Delay time (td): It is defined as the time during which the collector current rises from zero to 0.1ICS.
How does a Shockley diode work?
A Shockley diode uses a metal-semiconductor junction instead of a p-n semiconductor-semiconductor junction. This results in a device with a much lower forward bias voltage drop and much faster switching times.
What is an Esaki diode?
A diode is a semiconductor electrical component that allows an electric current in only one direction. A tunnel diode, or Esaki diode, is a special type of diode that can operate very quickly using quantum tunneling, allowing it to work even with microwave frequencies (current switching direction billions of times per second).
Why diode dose not allow to set voltage more than 0.7volts across it?
The barrier potential of the silicon diode is 0.7v if the applied voltage across it is more than this voltage then PN-junction of the diode breaks, once pn-junction breaks the voltage across the diode is constant, since it breaks at 0.7 this voltage will be constant and not exceed for any further increase in applied voltage -inform.mayaprasad@gmail.com The voltage across junction will only exceed from 0.7 volt (for silicon diode) in the case of reverse biasing the applied total voltage will appear across p-n junction. ANSWER: .7 VOLTS is an arbitrarily chosen number since a diode any diode have an exponential curve V vs I . This number is chosen when using a diodes but there are times when a greater or lesser voltage is chosen to reflect the application and the current trough the diode determine that. Example a diode gate diode will be chosen as .6 volts rather then .7v and a heavy conducting rectifier may have .8 volt to reflect closely the true value of the diode drop during real conditions
A bridge rectifier is supply with 120Vrms sinusoidal signal each diode has a junction voltage of 0.3V determine the peak votage?
v peak = v rms times square root (2) Note: A junction voltage of 0.3V is atypical. Normally a silicon diode has a forward voltage between 0.6 volts to 1.4V depending on current. Are you sure about the forward voltage? Perhaps you are talking about germanium or schottky diodes?
Define rms reverse voltage of a diode?
A DIODE will breakdown at a certain reverse voltage if RMS VOLTAGE IS SPECIFIED THEN the actual voltage will be RMS volts times 1.41
What is the PIV rating of diode?
A diode will provide saturating current if it reaches its Piv. What it should be well at least 1.5 of the applied reverse voltage. For AC at least 2 times to insure that the peak REVERSE voltage is blocked
What is hard switching in mosfet's?
I believe hard switching is fast on/off times with inductive loads. The fast rise and fall may create voltage spikes.
Can diode be used as transister?
No. A diode can not be used as a transistor. A diode allows electricity to flow in one direction like a one way street. A transistor works the same way as putting a stop light in the one way street. It lets electricity flow at certain times and keeps electricity from flowing at certain times. Of course a diode only works when electricity is there to flow just like a one way street only works when there are cars there to ride through it.
How does a diode convert AC to dc current explain by circuit diagram?
Normal house current is AC meaning it alternates on a wire first going one direction then the opposite. Standard AC is 60 hz meaning it does this 60 times per second. A diode allows current flow in one direction only. If you put a diode in an AC line, you will get pulses of current going only one direction on its backside because it refuses to conduct current in the opposite direction. Capacitive and inductive filters on the pulsing side of the diode smooth the current out so that it is no longer pulses going in one direction, it is a steady stream of electrons (DC).
Why jfet is called as junction field effect transistor?
Because the insulation between the gate and the channel is only a reverse biased PN junction. If this junction were to become forward biased the jfet would no longer operate as a transistor at those times.
What is the main component in inverters?
An inverter design and components vary with requirements but following components are most commonly used in designing an inverter. 1.microcontroller:Microcontroller is the main and integral part of an inverter. The main working of microcontroller is to control the switching of signals according to the requirements. 2.Bipolar Junction Transistor:BJT or a bipolar junction transistor is a three layered device which is capable of controlling the current flow. 3.Mosfets:The Metal-Oxide-Semiconductor-Field-Effect-Transistor (MOSFET) is a voltage controlled device and requires a very small input current.It is mainly used for switching of electronic signals as its switching speed is very high. 4.Filters:At times it is desirable to have circuits capable of selectively filtering one frequency or range of frequencies out of a mix of different frequencies in a circuit.
Why are FETs similar to diodes?
Junction Field Effect Transistors (JFET) have a single junction between the gate and channel, like a diode but they do not operate like diodes! The junction in a JFET must always be kept reverse biased for it to operate, the junction in a diode is usually expected to be forward biased sometimes and reverse biased at other times while operating.Metal Oxide Semiconductor Field Effect Transistors (MOSFET) have no junction between the gate and channel! Instead they have a silicon dioxide insulator layer. Diodes do not have an insulator layer.The feature that makes FETs operate entirely different from diodes is the channel between the source and drain contactson the semiconductor. By varying the potential on the gate of a FET relative to the potential on the channel the channel can be made to "pinch off" or "open up" thus varying its resistance. This can be used to create amplification in the circuit, which cannot be done using a diode.MOSFETs usually are built on a substrate and use a junction that is always reverse biased to prevent the substrate from short circuiting the channel.Note: most integrated circuits use this same reverse biased substrate junction structure to insulate the components of the circuit on the chip from the substrate semiconductor material to prevent it from short circuiting those components. These junctions are parasitic diodes not shown on the schematic of the integrated circuit, as they have no function except as insulation between components.
