how does zener diode act as voltage regulator
The zener diode can be used as a voltage regulator. Once the breakdown occurs, the potential difference across the diode does not increase even if the applied battery potential is increased. The (V-I) graph shows the characteristics of a zener diode. Even if the applied Voltage (Vi) fluctuates, the current through the load resistance 'RL' remains the same. The voltage across the diode practically remains the same.
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