1N5225B (DO-35)

Single Zener Diodes Overview

The Microsemi Corporation 1N5225B (DO-35) is a silicon unidirectional Zener diode housed in a hermetically sealed glass axial-lead DO-35 package. It provides a nominal Zener voltage of 3.0 V with a standard tolerance of ±5%, indicated by the 'B' suffix. The device operates within a temperature range of -65°C to +175°C and dissipates up to 0.5 watts at 25°C, derating to 0.48 W on FR4 PCBs. Key electrical parameters include a maximum reverse current of 29 μA at 2.7 V, a Zener impedance of 1600 Ohms at 20 mA, and a negative temperature coefficient of -0.075 %/°C.

Single Zener Diodes Feature Summary

• Hermetically sealed glass axial-lead construction for environmental stability
• Inherently radiation hard per MicroNote 050
• Minimal capacitance characteristics suitable for high-frequency applications
• Non-sensitive to electrostatic discharge

Single Zener Diodes Applications

• Voltage regulation over broad operating current and temperature ranges
• Reference voltage sources in precision circuits
• Protection against voltage transients

Single Zener Diodes Procurement Notes

Verify that the ordering prefix matches the required screening level, as prefixes like MQ, MX, MV, or MSP indicate specific military standards under MIL-PRF-19500. Confirm the presence of the 'e3' suffix if RoHS compliance is mandatory. Ensure the 'B' suffix is present to guarantee the specified ±5% voltage tolerance rather than the standard 10% tolerance associated with the 'A' suffix.

Single Zener Diodes Selection Notes

Select this component when a stable 3.0 V reference is required in harsh environments due to its radiation hardness and wide thermal operating range. The DO-35 package facilitates through-hole mounting. Consider tighter tolerance variants (suffixes C or D) if stricter voltage accuracy is needed, or verify that the low dynamic impedance at higher currents meets the circuit's load regulation requirements.

Single Zener Diodes Part Context

This part belongs to the popular 1N5221 through 1N5281B series of 0.5-watt Zener Voltage Regulators produced by Microsemi's Scottsdale Division. The series offers an extensive selection from 2.4 to 200 volts. While the base JEDEC numbers define the voltage, the suffix letters identify specific tolerances and features, allowing for precise customization of performance characteristics for various industrial and military applications.

Single Zener Diodes Replacement Considerations

Equivalent parts include other manufacturers' 1N5225B devices in the DO-35 package. For surface mount needs, MLL5225 equivalents are available in the DO-213AA MELF style. Military screened versions can be sourced using prefixes such as MQ, MX, MV, or MSP appended to the base number with the '-1' suffix.

Single Zener Diodes FAQ

What does the 'B' suffix signify for the 1N5225B?

The 'B' suffix indicates a standard voltage tolerance of plus or minus 5%. Without this suffix, the device typically carries a 10% tolerance.

Is the 1N5225B sensitive to electrostatic discharge?

No, the device is non-sensitive to ESD, having been tested according to MIL-STD-750 Method 1020.