Advantages and disadvantages of zener diode shunt regulator

Advantages:

There are some advantages of zener diode shunt regulator which are given below.

• The zener diode shunt regulator gives a better regulation over a wider range of load currents and input voltages.
• It gives higher current capability.
• The zener diode shunt is very economic as it is of low cost.
• It requires only two or three components.
• It has a very simple circuit.

Disadvantages:

There are some disadvantages of zener diode shunt regulator which are given below.

• The internal impedance of the circuit is high.
• The voltage regulation is poor.
• The output voltage is not adjustable because it has V_{O ­}= V_Z.
• It cannot be used for large load current.
• It has poor efficiency for heavy loads because a considerable amount of power is wasted in zener resistance (R₂) and series resistor (R_S) in comparison with load power.
• The DC output voltage slightly changes due to zener resistance.
• Changes in load current produce changes in zener current.
• Consequently the output voltage also changes.