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Why does the voltage across a Zener diode remain constant?
Therefore, the current through the Zener diode varies2 so as to keep the current through RL constant. The varying Zener current (and the steady load current) flows through Rs, which causes a varying voltage across Rs. This in turn allows the voltage across the load to remain constant.
How does a Zener diode regulate the load voltage?
Zener Diodes can be used to produce a stabilised voltage output with low ripple under varying load current conditions. By passing a small current through the diode from a voltage source, via a suitable current limiting resistor (RS), the zener diode will conduct sufficient current to maintain a voltage drop of Vout.
Does Zener diode maintains constant voltage across the load?
Due to change in input voltage or in load resistance, the output voltage across the zener diode does not change. Hence, the zener diode provides constant voltage across load.
Why the voltage across a Zener diode does not remain strictly constant with the changes in the Zener current?
In summary, the voltage point at which the voltage across the Zener diode becomes stable is called the Zener voltage, which ranges from less than a volt to hundreds of volts. This is important because once the voltage across a Zener diode exceeds its breakdown voltage, the voltage across the Zener remains constant.
When does the Zener diode conduct the least current?
Then for all other combinations of input voltage and load current the Zener diode conducts the excess current thus maintaining a constant voltage across the load. The Zener conducts the least current when the load current is the highest and it conducts the most current when the load current is the lowest.
Why is the Zener voltage increasing with the load resistance in this?
As the load resistance is kept being increased after a point why is the zener diode exceeds its rated zener voltage 8.2V? Technically, increasing the load impedance is decreasing the load, i.e., putting lower demands on the supply.
Is there a minimum or maximum Zener current?
There is a minimum Zener current, I z (min), that places the operating point in the desired breakdown. There is a maximum Zener current, I z (max), at which the power dissipation drives the junction temperature to the maximum allowed. Beyond that current the diode can be damaged.
Is it possible to increase the voltage by increasing the impedance?
Technically, increasing the load impedance is decreasing the load, i.e., putting lower demands on the supply. That said… You can easily get a voltage higher than the Zener voltage by pushing more than the Zener current through them.