1N5309UR-1/TR

Overview

The Microchip Technology 1N5309UR-1/TR is a surface-mount current regulator diode housed in the DO-213AB (MELF) package. It provides a nominal regulating current of 3.0 mA with standard tolerances ranging from 2.70 mA to 3.30 mA at a test voltage of 25 V. The device supports a peak operating voltage of 100 V and dissipates up to 500 mW of power. Electrical characteristics include a minimum regulator impedance of 0.029 MΩ and a maximum limiting voltage of 2.25 V. It operates within a temperature range of -65 °C to +150 °C.

Feature Summary

• Double-plug internal metallurgical bond construction for reliability
• High source impedance for stable current regulation
• Inherently radiation hard design
• ESD nonsensitive operation

Applications

• Current regulation over broad operating voltage ranges
• Temperature-compensated reference circuits
• Biasing networks for semiconductor devices

Procurement Notes

Verify that the ordering suffix /TR indicates tape and reel packaging per EIA-481-1-A standards. Confirm RoHS compliance status, as leadless packages may have specific commercial grade variations. Ensure the mounting surface Coefficient of Expansion matches the device's axial expansion rate of approximately +6 PPM/°C to prevent mechanical stress during thermal cycling.

Selection Notes

Select this component when a fixed current source is required across a wide voltage span. The 1N5309UR-1 offers a 3.0 mA nominal current. Compare against the 1N5283-1N5314 series for other current values. Verify that the 500 mW power dissipation rating accommodates the voltage drop across the device at the target operating current.

Part Context

This part belongs to the 1N5283UR-1 through 1N5314UR-1 family of 0.5 W current regulators. These devices serve as surface-mount equivalents to the legacy 1N5283 through 1N5314 axial-leaded series. The DO-213AB package provides a hermetically sealed glass case suitable for harsh environments.

Replacement Considerations

The 1N5309 (DO-7 axial package) is the direct axial-leaded equivalent. Military qualified variants such as JANTX1N5309UR-1 are available under MIL-PRF-19500/463 specifications.