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The voltage and current characteristics of a zener diode in the forward bias condition (anode more positive than cathode) are similar to an ordinary diode. Below the cutoff voltage, the current is near zero, excepting for leakage current. Starting at the turnon voltage, the diode starts to conduct. As voltage increases, current increases. At this point, increases in current result in very small increases in voltage. Above the breakdown current, the diode tends to self-destruct. The cutoff voltage for a silicon diode typically ranges from 0.6V to 0.7V, and the beginning of the flat region ranges from 0.7V to 1.4V, depending on the current rating of the diode. The cutoff characteristic is also highly dependent on temperature. It is important to understand that, while the current to voltage curve is relatively flat between the cutoff and breakdown points, it is not completely flat. This is normal diode behavior. In the reverse bias condition (anode more negative than cathode), the zener diode behaves very much like its forward bias condition, except that the cutoff voltage and flat region range are higher and, sometimes, flatter. This is what a zener is used for - it makes a good voltage regulator.
I depends on the voltage.
In a reverse bias condition of a circuit current initially remains the same for low voltage but at the breakdown voltage current increases fast even for a small increase in voltage.hence.........
The point in the forward operating region of the characteristic curve where conduction starts to increase rapidly is called Knee voltage of a PN Junction Diode.The breakdown voltage of a diode is the minimum reverse voltage to make the diode conduct in reverse.(or) Breakdown voltage is a parameter of a diode that defines the largest reverse voltage that can be applied without causing an exponential increase in the current in the diode.-- Dinakar
If resistance increases and voltage stays the same, then current decreases. Ohm's Law: Current equals Voltage divided by Resistance.
After breakdown voltage is reached in a zener diode the current increases drastically.
Knee voltage (cut in voltage) :-The forward voltage at which the current through the P-N Junction starts increasing rapidly is called as Cut in voltage or knee voltage Breakdown voltage :-It is the minimum reverse voltage at which the P-N Junction can conduct without damage to the current
The barrier voltage of a diode is 0.7v for silicon and 0.3 for germanium. after this voltage is reached the current starts increasing rapidly... till this voltage is reached the current increases in very small steps...
The voltage and current characteristics of a zener diode in the forward bias condition (anode more positive than cathode) are similar to an ordinary diode. Below the cutoff voltage, the current is near zero, excepting for leakage current. Starting at the turnon voltage, the diode starts to conduct. As voltage increases, current increases. At this point, increases in current result in very small increases in voltage. Above the breakdown current, the diode tends to self-destruct. The cutoff voltage for a silicon diode typically ranges from 0.6V to 0.7V, and the beginning of the flat region ranges from 0.7V to 1.4V, depending on the current rating of the diode. The cutoff characteristic is also highly dependent on temperature. It is important to understand that, while the current to voltage curve is relatively flat between the cutoff and breakdown points, it is not completely flat. This is normal diode behavior. In the reverse bias condition (anode more negative than cathode), the zener diode behaves very much like its forward bias condition, except that the cutoff voltage and flat region range are higher and, sometimes, flatter. This is what a zener is used for - it makes a good voltage regulator.
I depends on the voltage.
In a reverse bias condition of a circuit current initially remains the same for low voltage but at the breakdown voltage current increases fast even for a small increase in voltage.hence.........
If current increases, then voltage also has to increase, assuming that resistance stay relatively the same. Power will also increase. Since power is the product of voltage and current, then the power increase would be the square of the voltage or current change.
Ohm's law says Voltage = Current x Resistance. As voltage increases, currrent increases proportionally with a fixed load.
The point in the forward operating region of the characteristic curve where conduction starts to increase rapidly is called Knee voltage of a PN Junction Diode.The breakdown voltage of a diode is the minimum reverse voltage to make the diode conduct in reverse.(or) Breakdown voltage is a parameter of a diode that defines the largest reverse voltage that can be applied without causing an exponential increase in the current in the diode.-- Dinakar
If the resistance increases, while the voltage stays the same, current will decrease. Current = voltage divided by resistance
If resistance increases and voltage stays the same, then current decreases. Ohm's Law: Current equals Voltage divided by Resistance.
All diodes have a tiny voltage when current flows in a 'forward' direction. And a Reverse Breakdown voltage when current tries to flow in a reverse direction resulting in a high voltage. That current does not flow until voltage exceeds its breakdown number. Regular diodes have a reverse breakdown voltage that is somewhere above a number, For example a 1N4002 has a Reverse Breakdown Voltage somewhere above 100 volts. A Zener diode is constructed so that its Reverse Breakdown voltage is clearly defined and accurate. For example Reverse Breakdown voltage for a 1N4733 is 5.1 volts. A !N4734 is 5.6 volts.