1N4908A

Overview

The Microchip Technology 1N4908A is a temperature-compensated Zener diode designed for precision voltage regulation applications. 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, supporting a maximum power dissipation of 400 mW. Key electrical characteristics include a test current of 4 mA, a maximum reverse leakage current of 15 µA, and a Zener impedance of 50 Ohms. It offers an extended operating temperature range from -65°C to +175°C, ensuring stability in demanding environments.

Feature Summary

• Temperature compensated design ensures stable voltage regulation across wide thermal variations
• High reliability construction suitable for harsh industrial and military environments
• Precision voltage reference capability with tight manufacturing tolerances

Applications

• Precision voltage reference circuits requiring low temperature drift
• Overvoltage protection in sensitive electronic systems
• Voltage regulation in instrumentation and measurement equipment

Procurement Notes

Verify the specific suffix TR if reel packaging is required, as standard versions may come in bulk or tape-and-reel formats. Confirm RoHS compliance status directly with the manufacturer, as historical data indicates potential non-compliance for certain variants. Ensure the DO-7 package dimensions match your PCB footprint requirements before finalizing procurement decisions.

Selection Notes

Select this component when a stable 12.8 V reference is needed with minimal temperature coefficient. Compare against standard Zener diodes if high-temperature stability above 175°C is not required. Consider the 400 mW power rating to ensure adequate thermal headroom in your specific circuit layout and ambient conditions.

Part Context

The 1N4908A belongs to Microchip's legacy discrete diode portfolio, specifically within the temperature-compensated Zener series. This family is engineered to provide superior thermal stability compared to standard Zener diodes, making it suitable for critical analog applications where voltage drift due to heat could compromise system performance.

Replacement Considerations

Consult official Microchip documentation for direct cross-reference part numbers. Verify that any substitute maintains the 12.8 V nominal voltage, ±5% tolerance, and DO-7 package compatibility to ensure mechanical and electrical interchangeability.