1N3821

Single Zener Diodes Overview

The Microsemi 1N3821 is a silicon Zener diode with a nominal voltage of 3.3 V and a test current of 76 mA. It operates within a junction temperature range of -65°C to +175°C and dissipates up to 1 Watt at lead temperatures below 125°C. The device features a maximum Zener impedance of 10 Ohms at the test current and 400 Ohms at 1 mA. Reverse leakage current is limited to 1 µA at 1 V, with a typical temperature coefficient of -0.066 %/°C. It utilizes a DO-13 (DO-202AA) hermetically sealed metal package.

Single Zener Diodes Feature Summary

• Hermetically sealed welded metal and glass construction for radiation hardness
• Internally solder-bonded metallurgical connection for high reliability
• Low reverse leakage currents and ESD insensitivity
• Stable voltage regulation across broad operating current and temperature ranges

Single Zener Diodes Applications

• Voltage reference circuits in military environments
• High-reliability power supply regulation
• Radiation-hardened electronic systems
• Precision low-voltage clamping applications

Single Zener Diodes Procurement Notes

Verify the specific ordering suffix to confirm screening level and compliance. Prefixes such as JAN, JANTX, or JANTXV indicate MIL-PRF-19500/115 military qualification levels. The e3 suffix denotes RoHS compliance with annealed matte-Tin plating. Confirm the required tolerance and thermal mounting specifications before procurement.

Single Zener Diodes Selection Notes

Select this component for applications requiring a stable 3.3 V reference in harsh conditions. The DO-13 package supports direct heat sinking for improved thermal performance. Consider the negative temperature coefficient when designing for wide ambient temperature variations. Ensure the circuit current remains within the specified test and maximum limits.

Single Zener Diodes Part Context

This part belongs to the established 1N3821 through 1N3830A series of 1-Watt Zener diodes. The series covers low voltages from 3.3 V to 7.5 V in the same hermetic metal case. Higher voltage options are available in the 1N3016 through 1N3051 series using identical packaging. Surface mount equivalents exist in the UR-1 series.

Single Zener Diodes Replacement Considerations

Equivalent parts include JAN1N3821, JANTX1N3821, and JANTXV1N3821 for varying military screening levels. The 1N3821A variant offers a standard +/-5% voltage tolerance. Verify that replacement devices maintain the DO-13 package and hermetic sealing requirements.