1N4970

Single Zener Diodes Overview

The Microchip Technology 1N4970 is a 5-watt voidless hermetically sealed glass Zener diode from the 1N4954-1N4996 series. It features a nominal Zener voltage of 33V with a standard tolerance of ±5%. The device operates within a junction temperature range of -65°C to +175°C and dissipates up to 5 Watts at a lead temperature of 65°C. Key electrical characteristics include a maximum Zener impedance (ZZT) of 10 Ohms at a test current of 40mA, a maximum reverse leakage current of 2µA at 33V, and a continuous regulator current of 144mA. It utilizes axial leads with Tin/Lead finish and includes internal metallurgical bonds.

Single Zener Diodes Feature Summary

• Hermetically sealed voidless hard glass construction with tungsten slugs for high reliability
• Internal Category I metallurgical bonds ensuring robust mechanical integrity
• Triple-layer passivation providing enhanced protection against environmental stress
• Non-sensitive to electrostatic discharge per MIL-STD-750 Method 1020

Single Zener Diodes Applications

• High-reliability military and aerospace voltage regulation circuits
• Power supply reference standards requiring stable breakdown voltage
• Overvoltage protection in critical systems where failure is not tolerated
• Radiation-hardened electronic assemblies

Single Zener Diodes Procurement Notes

Verify that the component matches the specific Microsemi/Microchip datasheet revision G documentation for the 1N4954-1N4996 series. Confirm the presence of the correct marking, including part number and polarity band. Ensure the termination finish is Tin/Lead as specified for current inventory, noting that previous stock may have had solid Silver leads. Validate military qualification status if required by the application specification.

Single Zener Diodes Selection Notes

Select the 1N4970 when a precise 33V Zener reference is needed in a high-power 5W axial package. Consider this component for environments demanding extreme thermal stability and hermetic sealing. Evaluate the 10 Ohm dynamic impedance and 2µA leakage current against circuit sensitivity requirements. Choose this variant over surface-mount options when axial mounting or higher surge current handling is necessary for the design.

Single Zener Diodes Part Context

This component belongs to the industry-recognized 1N4954 through 1N4996 series of 5-watt Zener voltage regulators. Manufactured by Microsemi's Scottsdale Division, these devices are designed for applications where reliability is paramount. The series offers a wide voltage selection from 3.3V to 390V, with the 1N4970 specifically providing the 33V option within this robust glass-encapsulated family.

Single Zener Diodes Replacement Considerations

Direct substitutes within the same series include other 1N49xx part numbers with similar power ratings and package styles. For equivalent performance in different voltage ranges, consult the full 1N4954-1N4996 datasheet. Surface-mount equivalents are available with the 'US' suffix, such as 1N4970US, offering identical electrical characteristics in a MELF configuration.