Zener Diode Voltage Regulator Circuit

Last Updated on March 28, 2024

Simple Zener Diode Voltage Regulator Circuit designed to give 5 volt output from 9 volt input, you can replace the zener diode to get desired output voltage. For a simple voltage regulation in the circuit or design zerner diode is the cost effective solution.

We know zener diode is a two terminal active device and specially known for zener breakdown operation. A zener diode or Breakdown diode is a PN diode specially designed for operation in the breakdown region in the reverse bias condition. This diode operates in zener breakdown or avalanche breakdown, However the word zener is used for all components having sharp breakdown characteristics in reverse direction.

Zener Diode

Zener diode has two terminals as Anode (A) and Cathode (K) and it is made of heavily doped P and N semiconductors these two regions creates depletion region at the junction. This zener diode is designed to operate at breakdown region during reverse bias.

V-I Characteristics of Zener diode

Here zener breakdown or avalanche breakdown occurs at reverse bias after reaching the breakdown point in terms of reverse voltage and current afterwards zener diode allows constant voltage with different current level.

Circuit Diagram

Available Zener Diodes

1/2W	0.5W	0.5W	1W	1W
Voltage	DO-35	LL34	DO-41	LL41
2V0	BZX55C2V0	ZMM2V0
2V2	BZX55C2V2	ZMM2V2
2V4	BZX55C2V4	ZMM2V4
2V7	BZX55C2V7	ZMM2V7
3V0	BZX55C3V0	ZMM3V0	1N4727A	ZM4727A
3V3	BZX55C3V3	ZMM3V3	1N4728A	ZM4728A
3V6	BZX55C3V6	ZMM3V6	1N4729A	ZM4729A
3V9	BZX55C3V9	ZMM3V9	1N4730A	ZM4730A
4V3	BZX55C4V3	ZMM4V3	1N4731A	ZM4731A
4V7	BZX55C4V7	ZMM4V7	1N4732A	ZM4732A
5V1	BZX55C5V1	ZMM5V1	1N4733A	ZM4733A
5V6	BZX55C5V6	ZMM5V6	1N4734A	ZM4734A
6V2	BZX55C6V2	ZMM6V2	1N4735A	ZM4735A
6V8	BZX55C6V8	ZMM6V8	1N4736A	ZM4736A
7V5	BZX55C7V5	ZMM7V5	1N4737A	ZM4737A
8V2	BZX55C8v2	ZMM8V2	1N4738A	ZM4738A
9V1	BZX55C9V1	ZMM9V1	1N4739A	ZM4739A
10V	BZX55C10V	ZMM10	1N4740A	ZM4740A
11V	BZX55C11V	ZMM11	1N4741A	ZM4741A
12V	BZX55C12V	ZMM12	1N4742A	ZM4742A
13V	BZX55C13V	ZMM13	1N4743A	ZM4743A
15V	BZX55C15V	ZMM15	1N4744A	ZM4744A
16V	BZX55C16V	ZMM16	1N4745A	ZM4745A
18V	BZX55C18V	ZMM18	1N4746A	ZM4746A
20V	BZX55C20V	ZMM20	1N4747A	ZM4747A
22V	BZX55C22V	ZMM22	1N4748A	ZM4748A
24V	BZX55C24V	ZMM24	1N4749A	ZM4749A
27V	BZX55C27V	ZMM27	1N4750A	ZM4750A
30V	BZX55C30V	ZMM30	1N4751A	ZM4751A
33V	BZX55C33V	ZMM33	1N4752A	ZM4752A
36V	BZX55C36V	ZMM36	1N4753A	ZM4753A
39V	BZX55C39V	ZMM39	1N4754A	ZM4754A
43V	BZX55C43V	ZMM43	1N4755A	ZM4755A
47V	BZX55C47V	ZMM47	1N4756A	ZM4756A
51V	BZX55C51V	ZMM51	1N4757A
56V	BZX55C56V	ZMM56	1N4758A
62V	BZX55C62V	ZMM62	1N4759A
68V	BZX55C68V	ZMM68	1N4760A
75V	BZX55C75V	ZMM75	1N4761A

You can use any of these zener diode as a Regulator in your design and put exact Rs Resistor according to the zerner diode and output voltage specifications.

In this schematic a 5.1 Volt zener diode is used in reverse bias, when the input voltage increase or above the zener breakdown then zener starts to conduct voltage up to the breakdown voltage level and gives regulated output voltage.