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First off, I don't know if by current flow you mean conventional current flow or electron current flow. You realize they are in opposite directions and most electronics engineers use conventional current flow in circuit analysis.
Ignoring this, I will assume your real question is "Why does current flow backwards in zener diodes compared to ordinary diodes?" The answer is that zener diodes are not operated in the forward biased range as are ordinary diodes, instead they are operated in the reverse biased range. When reverse biased enough any diode reaches breakdown voltage and suddenly conducts. Most ordinary diodes can be destroyed by breakdown, but zener diodes are designed to tolerate it. In zener diodes, this breakdown is referred to as "zener breakdown" and the voltage it happens at the "zener voltage".
Low voltage zener diodes can still be used in the forward biased mode, like ordinary diodes. However most high voltage zener diodes have a "blocking diode" that is not documented on the data sheet to block forward biased operation. "Blocking diodes" are simply ordinary diodes wired in series with the zener; when the zener would be forward biased they are reverse biased (and thus blocking current), when the zener would be reverse biased they are forward biased.
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Which side of diode is anode and which is cathode on the diode in a schematic?
The anode is the arrow shaped end, while the cathode is the bar shaped end. You can remember this by recalling that current flows from anode to cathode in an ordinary diode; well, that is, if you use the trick of assuming that current is hole flow, rather than electron flow, a useful and common convention. The exception, of course, is the zener diode, where current flows in both directions, but at different potentials. In this case, there are two 45 degree angled bars at the end of the cathode symbol, and the normal configuration of current flow is cathode to anode, backwards with respect to an ordinary diode.
What is symbols of zener diode?
Usual symbol for diode is with a triangle - looking as an arrow hinged with a vertical line. Arrow head stands for anode for diode and line stands for its cathode. To give the symbol for zener diode we simply replace the vertical line by letter Z which also symbolizes the first designer 'Zener'
What is the leakage current of zener diode?
The leakage current of a (zener) diode is the current that leaks when a diode is connected in reverse biased.
Can you use zener diode for rectification purpose?
Yes **************************************** Yes they can but there are pitfalls. A normal diode will have a high reverse breakdown voltage. A zener has a relatively low breakdown voltage (its "zener"voltage). If a zener diode is used as a rectifier it must have a zener voltage at least twice the peak of the applied a.c.
What is Zener resistance of the Zener diode?
zener resistance of a zener diode is the resistance of the zener diode but which is the resistance of a diode
Which side of diode is anode and which is cathode on the diode in a schematic?
The anode is the arrow shaped end, while the cathode is the bar shaped end. You can remember this by recalling that current flows from anode to cathode in an ordinary diode; well, that is, if you use the trick of assuming that current is hole flow, rather than electron flow, a useful and common convention. The exception, of course, is the zener diode, where current flows in both directions, but at different potentials. In this case, there are two 45 degree angled bars at the end of the cathode symbol, and the normal configuration of current flow is cathode to anode, backwards with respect to an ordinary diode.
What is symbols of zener diode?
Usual symbol for diode is with a triangle - looking as an arrow hinged with a vertical line. Arrow head stands for anode for diode and line stands for its cathode. To give the symbol for zener diode we simply replace the vertical line by letter Z which also symbolizes the first designer 'Zener'
What is the leakage current of zener diode?
The leakage current of a (zener) diode is the current that leaks when a diode is connected in reverse biased.
What is leakage current of zener diode?
The leakage current of a (zener) diode is the current that leaks when a diode is connected in reverse biased.
Is the banded end of a diode positive or negative?
The Banded end of diode represents Cathode.If you want the diode to be forward biased then the Cathode is made more negative than Anode.For reverse biasing of Diode (Zener Diode) The Cathode is kept positive.However the mail carrier of current in the Cathode is Electrons which are negative.
Can you use zener diode for rectification purpose?
Yes **************************************** Yes they can but there are pitfalls. A normal diode will have a high reverse breakdown voltage. A zener has a relatively low breakdown voltage (its "zener"voltage). If a zener diode is used as a rectifier it must have a zener voltage at least twice the peak of the applied a.c.
How do you tell the difference between a cathode and anode?
A:The difference is potential a anode requires a positive potential and the cathode requires a negative potential ANSWER : I wander what a zener will behave with this explanation. Both have cathode and anode terminals
How much current draw zener diode?
It depends on the particular zener diode. Typically, they will pull 75 ma of current.
What type of diode maintains constant current?
zener diode
What diode people use before the invention of zener diode?
gas filled cold cathode glow discharge tubes.
What is Zener resistance of the Zener diode?
zener resistance of a zener diode is the resistance of the zener diode but which is the resistance of a diode
When current through a zener diode increases by a factor of 2 by what factor does the voltage across the zener diode increase?
If the zener diode is in zener breakdown the voltage across the zener diode remains constant regardless of current (for the ideal zener diode). Real zener diodes have parasitic resistance that causes the voltage across the zener diode to increase slightly with increased current, but due to temperature dependant variations in this parasitic resistance as well as temperature dependant variations in the zener breakdown voltage, this change in voltage in real zener diodes cannot be described by a simple linear factor.
