1N4905A/TR

Overview

The Microchip Technology 1N4905A/TR is a temperature-compensated Zener diode designed for precision voltage regulation. It features a nominal Zener voltage of 12.8 V with a tight tolerance of ±5%. The device operates in the DO-7 (DO-204AA) axial through-hole package, dissipating up to 400 mW. Key electrical parameters include a maximum reverse leakage current of 15 µA and a Zener impedance of 100 Ohms at a test current of 2 mA. The voltage temperature coefficient is specified at 0.005 %/°C. It supports an operating temperature range from -65°C to +175°C.

Feature Summary

• Temperature compensated design ensures stable voltage reference across wide thermal ranges
• Precision voltage regulation with tight manufacturing tolerance
• Robust axial leaded construction suitable for through-hole mounting

Applications

• Precision voltage reference circuits
• Temperature-stable power supply regulation
• Over-voltage protection in sensitive electronics

Procurement Notes

Verify the specific suffix TR indicates reel packaging when ordering. Confirm RoHS compliance status as documentation may vary by region or revision. Ensure the DO-7 package dimensions match the target PCB footprint. Cross-reference the manufacturer part number with official Microchip databases to confirm current production status and datasheet revisions before finalizing procurement specifications.

Selection Notes

Select this component when high thermal stability is required for voltage references. The 12.8 V rating suits applications needing precise mid-range regulation. Consider the 400 mW power dissipation limit for thermal management. The axial package requires adequate board spacing. Verify that the 100 Ohm impedance meets the circuit's dynamic load requirements.

Part Context

This component belongs to the 1N4905 series of temperature-compensated Zener diodes manufactured by Microchip Technology. These devices are engineered to minimize voltage drift due to temperature changes, making them superior to standard Zener diodes for precision analog applications. The series typically includes variants with different voltage ratings while maintaining similar compensation characteristics.

Replacement Considerations

Check for direct equivalents such as the 1N4905 without the A suffix if tolerance differences are acceptable. Verify pinout compatibility for DO-7 packages. Ensure substitute components meet the same 400 mW power rating and temperature coefficient specifications.