1N5256B

Single Zener Diodes Overview

The Microchip Technology 1N5256B is a 0.5 W glass axial-lead Zener diode in the DO-35 package. It provides a nominal Zener voltage of 30 V with a ±5% tolerance (B suffix). Key electrical parameters include a maximum reverse current of 100 µA at 20 V, a Zener impedance of 49 Ω at IZK = 0.25 mA, and a temperature coefficient of +0.091 %/°C. The device operates within a junction temperature range of -65°C to +175°C.

Single Zener Diodes Feature Summary

• Hermetically sealed glass axial-lead construction for reliable operation
• Provides stable voltage regulation across a broad operating current and temperature range
• Minimal capacitance characteristics suitable for high-frequency applications
• Inherently radiation hard per MicroNote 050

Single Zener Diodes Applications

• Voltage reference circuits requiring stable DC levels
• Overvoltage protection stages in electronic systems
• Power supply regulation modules

Single Zener Diodes Procurement Notes

Verify the specific manufacturer origin, as the component was originally JEDEC registered by Microsemi and is now produced under Microchip Technology. Confirm RoHS compliance status, which requires the 'e3' suffix on the part number. Ensure the required tolerance matches the B suffix designation for ±5% accuracy before finalizing procurement specifications.

Single Zener Diodes Selection Notes

Select this component when a 30 V breakdown voltage is required in a standard through-hole axial package. The 500 mW power dissipation rating supports steady-state operation provided thermal derating curves are followed. Verify that the positive temperature coefficient aligns with the circuit's thermal stability requirements compared to lower voltage alternatives.

Single Zener Diodes Part Context

This device belongs to the 1N5221 through 1N5281B series of 0.5 W Zener Voltage Regulators. The series offers a wide selection of voltages from 2.4 V to 200 V. The 1N5256B specifically occupies the mid-range voltage segment of this family, utilizing the standard DO-35 glass body package common to the entire line.

Single Zener Diodes Replacement Considerations

Surface mount equivalents are available in the MLL5221 to MLL5281B series using the DO-213AA MELF style package. For higher reliability screening levels, military variants such as JAN or JANTX versions can be sourced by adding specific prefixes to the base part number.

Single Zener Diodes FAQ

What is the maximum reverse leakage current specified for the 1N5256B?

The maximum reverse current is 100 µA when measured at a reverse voltage of 20 V.

How is the polarity indicated on the 1N5256B package?

The cathode is indicated by a band on the glass body. The diode must be operated with the banded end positive with respect to the opposite end for Zener regulation.