A Zener diode is a specific kind of diode that, not at all like a typical one, enables current to stream from its anode to its cathode, as well as in the reverse direction, when the supposed "Zener voltage" is reached. Zener diodes have an exceptionally doped p-n junction. Typical diodes will likewise fail with voltage flowing in the reverse direction, however the voltage and sharpness of the knee are not too characterized concerning a Zener diode. Additionally ordinary diodes are not intended to work in the breakdown state, but rather Zener diodes can dependably work in this state.
Zener diode was named after Clarence Melvin Zener, who found the Zener impact. Zener reverse breakdown is because of electron quantum burrowing caused by a high quality electric field. In any case, numerous diodes depicted as "Zener" diodes depend rather on avalanche breakdown. Both breakdown sorts are utilized in Zener diodes with the Zener impact prevailing under 5.6 V and avalanche breakdown above.
Zener diodes are broadly utilized as a part of electronic appliances of various types and are one of the essential building blocks of electronic circuits. They are utilized to create low power stable supply rails from a higher voltage and to give reference voltages to circuits, particularly stable power supplies. They are likewise used to shield circuits from over-voltage, particularly electrostatic release.
| NGN 899.00 |
| Qty: Add to Cart |
| Currently item(s) in cart. |
 |
Included in this package:
- BZX55C: 3V3 or 3.3V (5 pieces)
- BZX55C: 4V7 or 4.7V (5 pieces)
- BZX55C: 5V1 or 5.1V (5 pieces)
- BZX55C :6V2 or 6.2V (5 pieces)
- BZX55C: 6V8 or 6.8V (5 pieces)
- BZX55C: 7V5 or 7.5V (5 pieces)
- BZX55C: 8V2 or 8.2V (5 pieces)
- BZX55C: 9V1 or 9.1V (5 pieces)
- BZX55C: 10V or 10.0V (5 pieces)
- BZX55C: 12V or 12.0V (5 pieces)
- BZX55C: 15V or 15.0V (5 pieces)
- BZX55C: 18V or 18.0V (5 pieces)
- BZX55C: 24V or 24.0V (5 pieces)
- BZX55C: 30V or 30.0V (5 pieces)
Operation of Zener Diodes
A customary solid state diode permits huge current in the event that it is reverse-biased over its reversed breakdown voltage. At the point when the reverse-biased breakdown voltage is surpassed, an ordinary diode is liable to high current because of avalanche breakdown. Unless this current is restricted by how the circuit is designed, the diode might be forever damaged because of overheating. A Zener diode shows nearly similar properties, aside from the fact that the device is uniquely constructed in order to have a lessened breakdown voltage, the purported Zener voltage. When we compare and contrast it with the ordinary diode, a reverse-biased Zener diode shows a controlled breakdown and enables the current to keep the voltage over the Zener diode near the Zener breakdown voltage. For instance, a diode with a Zener breakdown voltage of 3.2 V shows a voltage drop of practically 3.2 V over an extensive values of reverse currents. The Zener diode is in this manner perfect for applications, for example, to produce a reference voltage, for example, for an amplifier stage, or as a voltage stabilizer for low-current applications.A similar mechanism that creates a comparative effect is the avalanche effect as in the avalanche diode. The two sorts of diode are in reality developed similar way and the two effects are available in diodes of this sort. In silicon diodes up to around 5.6 volts, the Zener effect is the overwhelming effect and exhibits a high negative temperature coefficient. Over 5.6 volts, the avalanche effect winds up noticeably and displays a positive temperature coefficient.
In a 5.6 V diode, the two effects happen together, and their temperature coefficients almost offset each other, in this manner the 5.6 V diode is valuable in temperature-sensitive applications. An option, which is utilized for voltage references that should be profoundly steady for a long period of time, is to use a Zener diode with a temperature coefficient (TC) of +2 mV/°C, a breakdown voltage 6.2– 6.3 V, and in series connection with a forward-biased silicon diode (or a transistor B-E junction) produced on the same chip. The forward-biased diode has a temperature coefficient of −2 mV/°C, making the TCs counterbalance.
Present day fabricating methods have delivered Zener diodes with voltages lower than 5.6 V with insignificant temperature coefficients, yet as higher-voltage devices become predominant, the temperature coefficient rises drastically. A 75 V diode for example, has 10 times the coefficient of a 12 V diode.
Zener and avalanche diodes, despite breakdown voltage, are generally advertised under the umbrella term of "Zener diode". Under 5.6 V, where the Zener effects rules, the IV curve close to breakdown is significantly more adjusted, which calls for more care in focusing on its biasing conditions. The IV curve for Zeners over 5.6 V is significantly more sharper at breakdown.
0 Reviews:
Post a Comment