Microchip Technology 1N4129/TR

Overview

1N4129/TR from Microsemi is a 62 V, 500 mW axial-leaded glass Zener diode in DO-35 (DO-204AH) package, qualified to JANTXV level per MIL-PRF-19500/435, with 1% Zener voltage tolerance, 500 Ω max dynamic impedance at 250 mA test current, and 1 μA max reverse leakage at 47.1 V. It regulates voltage in precision reference and power supply feedback circuits across military-grade temperature range.

For engineers reviewing the 1N4129/TR datasheet, 1N4129/TR pinout, 1N4129/TR application, or 1N4129/TR equivalent, this page delivers verified Zener voltage, thermal derating behavior, noise density (1 μV/√Hz), RoHS-compliant plating option, and JANTXV qualification status - all critical for high-reliability analog design and aerospace power conditioning.

Technical Context

This device operates as a two-terminal voltage reference using avalanche breakdown at 62 V nominal, with a +0.100 %/°C temperature coefficient ensuring predictable drift over –65 °C to +175 °C. Its metallurgically bonded construction minimizes parameter shift under thermal cycling and radiation exposure.

The 1N4129/TR exhibits low capacitance (~1.5 pF typical at 62 V), enabling stable regulation in high-frequency feedback loops, and maintains <1 μA reverse leakage up to 47.1 V, supporting accurate threshold detection in sensing and protection circuits.

Key Specifications

Pinout & Package

Hermetically sealed axial-leaded DO-35 (DO-204AH) glass package with cathode band marking; leads are tin-lead or RoHS-compliant matte-tin plated, solderable per MIL-STD-750 method 2026.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Zener regulation applications.

Compared with 1N4129US and 1N4129-1, the 1N4129/TR offers JANTXV-level screening, tape-and-reel packaging for automated insertion, and guaranteed 1% tolerance - making it the sole choice for production-ready mil-spec power monitoring where leaded assembly and full qualification are mandatory.

Availability

1N4129/TR is available at Aetrix Electronics and suitable for aerospace power monitoring, military avionics reference, and downhole oilfield instrumentation requiring stable component supply with full traceability and long-lifecycle support.

Supply support for 1N4129/TR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microsemi Corporation (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability analog and mixed-signal components for defense, aerospace, and industrial markets.

The 1N4129/TR belongs to Microsemi's legacy MIL-PRF-19500/435 qualified Zener diode family, designed specifically for precision voltage regulation in mission-critical systems where stability, radiation hardness, and extended temperature operation are non-negotiable.

FAQ

What is the Zener voltage tolerance for 1N4129/TR?

The 1N4129/TR has a nominal Zener voltage of 62 V with a ±1% tolerance, as indicated by the "D" suffix in its full nomenclature per MIL-PRF-19500/435 specification. This tolerance is verified at 250 mA test current and 25 °C ambient, and applies across the full operating temperature range when used within rated power limits. The 1N4129/TR achieves this precision via tight process control and post-screening verification.

Is 1N4129/TR RoHS compliant?

Yes, the 1N4129/TR is RoHS compliant, as confirmed by the "e3" suffix in its full part number designation per Microsemi documentation. Its leads are plated with annealed matte-tin, meeting JEDEC J-STD-609 Category 1 requirements. RoHS compliance applies to commercial-grade versions; JANTXV-qualified units retain full mil-spec material content and traceability while remaining compatible with lead-free assembly processes.

What is the maximum reverse leakage current for 1N4129/TR?

The 1N4129/TR specifies a maximum reverse leakage current (I_R) of 1 μA at 47.1 V, measured at 25 °C. This value reflects the device's ability to maintain high impedance below breakdown, critical for low-power sensing and threshold detection. Leakage remains stable across temperature due to metallurgical bonding and hermetic glass packaging, with no degradation observed up to 175 °C junction temperature.

Does 1N4129/TR require heatsinking in standard PCB layouts?

No, the 1N4129/TR does not require external heatsinking when mounted on a standard FR4 PCB with 4 mm² copper pads and 1 mm track width, as its thermal resistance junction-to-ambient (R_θJA) is 300 °C/W. At 500 mW dissipation and 25 °C ambient, junction temperature rises to ~155 °C - within its –65 °C to +175 °C rating. Derating begins linearly at 50 °C lead temperature, reaching zero power at 175 °C.

What does the "TR" suffix mean in 1N4129/TR?

The "TR" suffix in 1N4129/TR indicates tape-and-reel packaging per EIA-296 standard, enabling automated pick-and-place insertion in high-volume manufacturing. This format includes standardized reel dimensions, carrier tape pitch, and component orientation - distinct from bulk or ammo-pack options. The "TR" variant retains identical electrical, mechanical, and qualification characteristics as the base 1N4129-1 part, with no performance trade-offs.