1N4739AP/TR12

Overview

The Microchip Technology 1N4739AP/TR12 is a silicon Zener diode with a nominal voltage of 9.1 V and a 5% tolerance. It operates in the DO-41 axial package, dissipating up to 1 W at 25°C ambient temperature. The device features a maximum dynamic impedance of 5 Ohms at a test current of 28 mA and a reverse leakage current of 10 µA at 7 V. It withstands surge currents up to 700 mA and functions within a temperature range of -65°C to +150°C.

Feature Summary

• Provides stable voltage regulation across a broad operating current and temperature range
• Features flexible axial-lead mounting terminals for standard through-hole applications
• Constructed with a void-free transfer molded thermosetting epoxy body

Applications

• Voltage regulation circuits requiring precise reference levels
• Protection against overvoltage transients in electronic systems
• Clipping and clamping applications in signal processing

Procurement Notes

Verify that the part number suffix TR12 corresponds to tape and reel packaging as specified by EIA-296 standards. Confirm RoHS compliance status if required, noting that the 'e3' suffix indicates lead-free plating while the base AP designation may differ. Ensure the supplier provides documentation confirming the plastic encapsulation type and JEDEC registration for the 1N4739A series.

Selection Notes

Select this component when a 9.1 V reference with 5% tolerance is needed in an axial package. Consider the 1 W power dissipation limit and thermal resistance characteristics for heat management. Compare against glass-body options if lower thermal resistance or specific environmental sealing is required. Verify that the 5 Ohm dynamic impedance meets the circuit's stability requirements.

Part Context

This component belongs to the 1N4728A through 1N4764A series of 1.0 watt Zener diodes manufactured by Microsemi (now Microchip Technology). The series offers extensive voltage selection from 3.3 to 100 volts. The 'AP' suffix designates plastic construction, which provides lower thermal resistance compared to the glass-body 'G' suffix option for the same JEDEC part numbers.

Replacement Considerations

Surface mount equivalents are available as SMAJ4739A and MLL4739A. Tighter tolerance versions exist with C (2%) or D (1%) suffixes. Military screening options are accessible via MQ, MX, MV, or MSP prefixes.