Zener Diode

1. ZENER DIODE
Dr.B.A.Sapna
KIT-CBE

2. Introduction to Zener Diodes
A Zener diode is a highly doped semiconductor device specifically
designed to function in the reverse direction. It is engineered with a
wide range of Zener voltages (Vz), and certain types are even adjustable
to achieve variable voltage regulation.

3. What is a Zener Diode?
● A Zener diode is a special type of rectifying diode that can handle breakdown
due to reverse breakdown voltage without failing completely.
● Here we will discuss the concept of using diodes to regulate voltage drop
and how the Zener diode operates in reverse-bias mode to regulate voltage
in a circuit.

4. Zener Diode Symbol
The circuit diagram symbol used to represent a Zener diode is drawn
with an arrow, representing forward bias current

5. Zener Breakdown
● The PN junction is formed by the combination of the p-type and the n-type
semiconductor material. The combination of the P-type and N-type regions
creates the depletion region.
● The width of the depletion region depends on the doping of the P and N-type
semiconductor material. If the material is heavily doped, the width of the
depletion region becomes very thin.

6. ZENER EFFECT

7. Zener Diode Specifications
● Zener/Breakdown Voltage – The Zener or the reverse breakdown
voltage ranges from 2.4 V to 200 V, sometimes it can go up to 1
kV while the maximum for the surface-mounted device is 47 V.
● Current Iz (max) – It is the maximum current at the rated Zener
Voltage (Vz – 200μA to 200 A)

8. Zener Diode Circuits

9. Applications of Zener Diodes
● Voltage regulation
● Signal clamping
● Voltage reference
● Overvoltage protection

10. ADVANTAGES
● The Zener diode is less expensive than another diode
● This diode can be used in regulate and stabilize the voltage in a
circuit
● These diodes have a high-performance standard
● Control the flowing current
● Compatibility and obtainability

11. DISADVANTAGES
● Zener diode cancels out voltage by applying an even larger voltage in the
reverse direction wasting electricity in the process.
● A Zener diode has a relatively poor regulation ratio and is generally not as
good as the transistor.