Not 100% sure, but I believe it's the reverse current at which a Zener diode enters breakdown. There is also the Zener max current which refers to the current that must not be exceeded if you do not wish to damage the device and also the Zener test current at which the Zener Voltage is measured. The test current usually lies somewhere (roughly halfway) between the knee and max current.
A: They are both diodes. The difference lies in the application. A rectifier is used to rectify AC current into pulsating current. The zener diode is used to regulate a voltage source to the zener voltage when connected in the reverse direction. ************************************************************** If you look at the characteristic curves of a rectifier diode and a zener diode, you will see that they are similar, but the reverse curve of the zener has a much sharper bend at what is called the "knee". It is at this point on the zener's curve at which it operates.
ZENER DIODE IS MADE TO REVERSE BREAK OVER AT A CERTAIN VOLTAGE the break over knee is not exactly sharp especially in low voltage zeners. and p-n means positive and negative junction
A: 6.2 volts for zeners are very sharp. Lower then that the knee is sloppy and above the sharpness decreases. A 3,2 v zener maybe nothings more then diodes in series, The sharpness of the knee is more pronounced into Vbe breakdown of transistors however the voltage cannot be predicted
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 knee point voltage of a CT is the voltage at the "knee" of a I-V characteristic (if you increase voltage, and plot this voltage with respect to the current flow, you will see a logorithmic type response). The knee is usually specified as 10% distortion (ie, the voltage is 10% less than you would expect relative to the current flow). beyond the knee point, the CT is considered in saturation. This applies to amplifiers / transistors as well as CTs. Transistors used as ampifiers are operated in the "linear region", or the region below the knee point of that particular transistors I-V characteristic.
A: Perfect example is a zener. As input voltage increases the current at the knee increases almost linearly at the zener voltage. If the inputs varies up or down then the current will vary up or down at the preset voltage making a zener a voltage regulator because of this feature
A: They are both diodes. The difference lies in the application. A rectifier is used to rectify AC current into pulsating current. The zener diode is used to regulate a voltage source to the zener voltage when connected in the reverse direction. ************************************************************** If you look at the characteristic curves of a rectifier diode and a zener diode, you will see that they are similar, but the reverse curve of the zener has a much sharper bend at what is called the "knee". It is at this point on the zener's curve at which it operates.
A zener diode is designed to be operated in reverse bias, and have a specified breakdown voltage. For example, if you wanted a part that is supposed to get 10V applied to it, and you only have a 12V rail, you can put a resistor and a 10V zener diode in series, and the zener diode will make sure that only 10V get dropped across it. Any more and it will begin conducting. It will draw enough current to drop the excess voltage across the series resistor. If the load on the output terminals increases, tending to reduce the output voltage, the Zener just takes less current. The idea is that the total current through the series resistor is enough to stabilise the output at 10V. ANSWER: A zener is a diode that has the property that when reversed bias is applied to exibit a breakdown of a voltage with a sharp knee. This property can be used as a regulator since the voltage will not change it the current trough the zener changes.
knee current
Zener Diode is nothing but a Crystal P-n junction diode in which the P type and n-type layers are heavily doped.Zener diode is mainly used as voltage regulator its forward charaqcteristic is same as normal p-n junsction diode but its reverse Characteristic is different that when the reverse region reaches knee region in spite of changes in current the voltage remains the same
ZENER DIODE IS MADE TO REVERSE BREAK OVER AT A CERTAIN VOLTAGE the break over knee is not exactly sharp especially in low voltage zeners. and p-n means positive and negative junction
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
A: 6.2 volts for zeners are very sharp. Lower then that the knee is sloppy and above the sharpness decreases. A 3,2 v zener maybe nothings more then diodes in series, The sharpness of the knee is more pronounced into Vbe breakdown of transistors however the voltage cannot be predicted
Information regarding knee exercises can be acquired in two places depending your current need, a hospital if it refers to knee pain, or a gym fro exercises regarding the knee's performance.
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
pn junction diode conducts current in one directions where as the zener diode conducts in both the directions. large current flow damage the PN junction diode but zener diode conducts eventhough there is a large current........
The knee refers to the shape of the curve when plotting voltage vs current in forward biased semiconductor junctions. Knee voltage, or threshold voltage, varies with device construction, doping level, and operating temperature among other parameters. This is due to the bandgap at the PN junctions of the diode. Therefore, even when forward biased, little current will flow until the diodes threshold voltage is exceeded. Threshold voltages for common silicon diodes is approximately 0.7V, and for Schottky devices near 0.3V. Germanium based diodes exhibit lower voltage thresholds than silicon based diodes, but are less common due to other limitations. All diodes also exhibit a reverse bias breakdown. Engineers normally avoid operation small signal and rectifier diodes in this mode by selecting a device with a reverse voltage specification much higher than expected voltages. However; zener diodes are specially constructed and doped to produce a relatively low reverse breakdown voltage which is commonly used in shunt regulators and overvoltage protection circuits. Various values of zener voltage are available.