What is the role of Zener diode in voltage limiter circuit?

What is the role of Zener diode in voltage limiter circuit?

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.

How do you calculate Zener current limiter resistor?

Circuit design example

  1. 12 – 5.1 = 6.9 volts. Determine the resistor current. Choose this to be 15 mA.
  2. 15 mA x 5.1 volts = 76.5 mW. This is nicely within the maximum limit for the diode. Determine the current through the series resistor.
  3. 6.9 / 17 mA = 0.405 kohm. The nearest value is 390 ohms.

How can you make a voltage regulator using Zener diode explain its operation?


  1. Set the Zener Voltage(VZ)
  2. Set the Series Resistance (RS) value.
  3. Set the Load Resistance (RL) value.
  4. Vary DC voltage.
  5. Voltmeter is placed parallel to load resistor and ammeter series with the series resistor.
  6. Choose appropriate DC voltage such that zener diode is ‘on’.

What is the purpose of a Zener diode in a circuit?

Zener diodes are used for voltage regulation, as reference elements, surge suppressors, and in switching applications and clipper circuits. The load voltage equals breakdown voltage VZ of the diode. The series resistor limits the current through the diode and drops the excess voltage when the diode is conducting.

What is the purpose of using Zener diode?

Zener diodes are widely used in electronic equipment of all kinds and are one of the basic building blocks of electronic circuits. They are used to generate low-power stabilized supply rails from a higher voltage and to provide reference voltages for circuits, especially stabilized power supplies.

What is used to limit the Zener current?

Zener diode basics The voltage across the terminals will be nearly constant between the breakdown current—or “knee current”—Iz(min) and the maximum current rating Iz(max). In real applications a resistor is used to limit current flow through a Zener diode, as shown in figure 2.

What is the working principle of Zener diode?

A Zener diode operates just like a normal diode when it is forward-biased. However, when connected in reverse biased mode, a small leakage current flows through the diode. As the reverse voltage increases to the predetermined breakdown voltage (Vz), current starts flowing through the diode.

What is the purpose of Zener diode?

A Zener diode permits Zener current, Iz, to flow when the voltage is above the specified Zener voltage. Thus, a Zener diode can be used for voltage detection by sensing Zener current with some other device.

What is the difference between a diode and a Zener diode?

A diode is a semiconductor device which conducts in one direction only. A Zener diode is a semiconductor device which conducts in forward biased as well as reversed biased. A normal diode if operated in reversed biased will get destroyed.