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The Zener diode's operation depends on the heavy doping of its p–n junction. The depletion region formed in the diode is very thin (< 1 μm) and the electric field is consequently very high (about 500 kV/m) even for a small reverse bias voltage of about 5 V, allowing electrons to tunnel from the valence band of the p-type material to the ...
In electronics, the Zener effect (employed most notably in the appropriately named Zener diode) is a type of electrical breakdown, discovered by Clarence Melvin Zener. It occurs in a reverse biased p-n diode when the electric field enables tunneling of electrons from the valence to the conduction band of a semiconductor , leading to numerous ...
In the Zener diode, the concept of PIV is not applicable. A Zener diode contains a heavily doped p–n junction allowing electrons to tunnel from the valence band of the p-type material to the conduction band of the n-type material, such that the reverse voltage is "clamped" to a known value (called the Zener voltage), and avalanche does not ...
Avalanche diodes (commonly encountered as high voltage Zener diodes) are constructed to break down at a uniform voltage and to avoid current crowding during breakdown. These diodes can indefinitely sustain a moderate level of current during breakdown. The voltage at which the breakdown occurs is called the breakdown voltage.
The transfer characteristic has exactly the same shape of the previous basic configuration, and the threshold values are the same as well. On the other hand, in the previous case, the output voltage was depending on the power supply, while now it is defined by the Zener diodes (which could also be replaced with a single double-anode Zener diode).
For example, the voltage of C 4 in the example would be at most 2U s - 4U f since there are 4 diodes between its positive terminal and the source. The total output voltage would be U(C 2) + U(C 4) = (2U s - 2U f) + (2U s - 4U f) = 4U s - 6U f. In a cascade with n stages of two diodes and two capacitors, the output voltage is equal to 2n U s - n ...
Here, the load current I R2 is supplied by the transistor whose base is now connected to the Zener diode. Thus the transistor's base current (I B) forms the load current for the Zener diode and is much smaller than the current through R 2. This regulator is classified as "series" because the regulating element, viz., the transistor, appears in ...
Clipping changes the shape of the waveform and alters its spectral components. A clipping circuit consists of linear elements like resistors and non-linear elements like diodes or transistors, but it does not contain energy-storage elements like capacitors. Clipping circuits are also called slicers or amplitude selectors. [1]