Ad
related to: zener diode problems with solution
Search results
Results from the WOW.Com Content Network
Severely overloaded Zener diodes in reverse bias shorting. A sufficiently high voltage causes avalanche breakdown of the Zener junction; that and a large current being passed through the diode causes extreme localised heating, melting the junction and metallisation and forming a silicon-aluminium alloy that shorts the terminals.
For example, a diode with a Zener breakdown voltage of 3.2 V exhibits a voltage drop of very nearly 3.2 V across a wide range of reverse currents. The Zener diode is therefore well suited for applications such as the generation of a reference voltage (e.g. for an amplifier stage), or as a voltage stabilizer for low-current applications. [2]
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 ...
These diodes can indefinitely sustain a moderate level of current during breakdown. The voltage at which the breakdown occurs is called the breakdown voltage . There is a hysteresis effect; once avalanche breakdown has occurred, the material will continue to conduct even if the voltage across it drops below the breakdown voltage.
Shockley derives an equation for the voltage across a p-n junction in a long article published in 1949. [2] Later he gives a corresponding equation for current as a function of voltage under additional assumptions, which is the equation we call the Shockley ideal diode equation. [3]
When the absorber is in the primary circuit, e.g. a Zener diode (or LED) with voltage V z connected "backwards" across the primary windings, the current waveshape is a triangle with the time t open determined by the formula I p = I peak,m - V z ×T open /L p, here I peak,m being the primary current at the time the switch opens. When the ...
In addition, failure of a single component can result in unacceptably high voltages at the output. For instance, if the Zener diode in the circuit shown should fail open, there will result a gradually-rising voltage at the output, eventually reaching the input (AC) voltage. [4] Capacitive power supplies typically have a low power factor.
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 ...
Ad
related to: zener diode problems with solution