6. Zener Diode

Surface Mount Devices

Part Number

Package

Zener Voltage (Vz)

Power Dissipation

BZT52C2V0S~ BZT52C75S

SOD-323

2.0V~39V

0.20W

MMSZ5221BS~ MMSZ5263BS

SOD-323

2.4V~43V

0.20W

BZT52C2V0~ BZT52C75

SOD-123

2.0V~51V

0.50W

MMSZ5221B~ MMSZ5267B

SOD-123

2.4V~43V

0.50W

ZMM55 Series

Mini-MELF

6.2V~200V

0.50W

08ZSMF Series

SOD123FL

5.1V~200V

0.80W

SMF4735A~ SMF4771A

SOD123FL

2.4V~36V

1.00W

DL4728A~DL4764A

MELF (DL-41)

3.3V~100V

1.00W

1SMA4728~1SMA200A

SMA (DO-214AC)

6.8V~400V

1.00W

1SMA5913A~1SMA5957A

SMA (DO-214AC)

3.3V~240V

1.50W

SZ453G~SZ45D0

SMA (DO-214AC)

3.3V~200V

2.00W

BZG03C6V2~BZG03C270

SMA (DO-214AC)

6.2V~270V

3.00W

1SMB5913B~1SMB5956B

SMB (DO-214AA)

3.3V~200V

3.00W

SMBJ5333B~SMBJ5388B

SMB (DO-214AA)

3.3V~200V

5.00W

Lead Devices

Part Number

Package

Zener Voltage (Vz)

Power Dissipation

BZX55 Series

DO-35

2.4V~36V

0.50W

1N4728A~1EZ400A

DO-41

3.3V~400V

1.00W

2EZ3.6A~3EZ200A

DO-41

3.6V~200V

2.00W

3EZ3.9A~3EZ400A

DO-15

3.9V~400V

3.00W

1N5333B-1N5388B

DO-15

3.9V~400V

5.00W

1N5333B~1N5388B

DO-201AE

3.3V~200V

5.00W

Introduction of Zener Diode:

Solid state voltage regulator diodes or Zeners have been popular since the late 1950's when they replaced bulky vacuum tubes. Discrete zeners ranging from 500 mW to 5 watts or less have particularly remained a commonly used semiconductor product, despite the evolution of integrated circuits. High power zeners above 5 watts have increasingly been replaced by regulator ICs for power supply outputs, nevertheless power zeners are still used in a variety of areas.

A zener diode is a specially processed single PN junction that provides relatively constant voltage across two terminal despite changes in zener current. Because of this unique characteristic, it is used as a voltage regulator when placed in parallel across a load to be regulated. In special compensated multiple PN junction configurations, it may also be used as a "Zero-TC" reference voltage diode for very small changes in voltage over a wide operating temperature range.