Microchip Technology 1PMT5939B/TR13

Overview

1PMT5939B/TR13 from Microsemi is a 39 V, ±5% tolerance surface-mount Zener diode in the Powermite® package, rated for 3.0 W DC power dissipation at TAB 1 = 60°C, with 45 Ω dynamic impedance at 9.6 mA test current and 900 µA max reverse leakage at 29.7 V. It serves as a precision voltage reference or overvoltage clamp in compact DC power rails.

For engineers reviewing the 1PMT5939B/TR13 datasheet, 1PMT5939B/TR13 pinout, 1PMT5939B/TR13 application, or 1PMT5939B/TR13 equivalent, key selection criteria include Zener voltage tolerance, thermal resistance (30°C/W junction-to-TAB), ESD rating (>16 kV HBM), low knee impedance, and compatibility with automated SMT assembly.

Technical Context

This device operates as a two-terminal voltage-regulating diode with sharp Zener breakdown at 39 V nominal. Its Powermite® package integrates a full metallic bottom and locking tab for mechanical stability and thermal conduction to PCB copper, enabling reliable 3.0 W power handling without external heatsinking.

Electrical behavior is defined at TL = 30°C with IZT = 9.6 mA; Zener voltage drift with temperature is managed via tight process control, and reverse leakage remains ≤900 µA up to VR = 29.7 V - supporting stable regulation in low-power sensing and biasing circuits.

Key Specifications

Pinout & Package

Package: Powermite® surface-mount molded package with full metallic bottom and integral heat-sink locking tab; cathode designated by TAB 1; weight ≈ 0.016 g; DO-216 outline.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMCJ39A and BZX84-C39, the 1PMT5939B/TR13 uniquely combines 3.0 W continuous Zener regulation, metallic-tab thermal conduction, and low-leakage performance - making it irreplaceable in high-stability, medium-power reference and clamping roles.

Availability

1PMT5939B/TR13 is available at Aetrix Electronics and suitable for industrial sensor biasing, DC power rail clamping, and automotive body control unit designs requiring stable component supply across extended production lifecycles.

Supply support for 1PMT5939B/TR13 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 (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability analog, mixed-signal, and radiation-tolerant components for aerospace, defense, and industrial markets.

The Powermite® Zener series, including the 1PMT5939B/TR13, was engineered for high-power-density voltage regulation in space-constrained, thermally demanding environments - particularly where automated assembly and long-term reliability are critical.

FAQ

What is the Zener voltage tolerance of the 1PMT5939B/TR13?

The 1PMT5939B/TR13 has a standard Zener voltage tolerance of ±5% at 39 V, measured at 9.6 mA test current and TAB temperature of 30°C. Tighter tolerances (±2% and ±1%) are available with suffixes C and D respectively, but the base 1PMT5939B/TR13 uses the ±5% grade.

How is thermal management handled in the 1PMT5939B/TR13 package?

The 1PMT5939B/TR13 uses a Powermite® package with a full metallic bottom and integral locking tab that serves as both mechanical anchor and primary thermal path. Its 30°C/W junction-to-TAB thermal resistance requires direct soldering of TAB 1 to a copper pour to achieve the rated 3.0 W dissipation at 60°C tab temperature.

Is the 1PMT5939B/TR13 suitable for automated SMT assembly?

Yes, the 1PMT5939B/TR13 is fully compatible with automated insertion equipment and supplied in EIA-481 standard tape-and-reel format (7-inch reel: 3,000 pcs; 13-inch reel: 12,000 pcs). Its Powermite® geometry and locking tab ensure stable orientation and placement accuracy during pick-and-place operations.

What is the maximum reverse leakage current for the 1PMT5939B/TR13?

The 1PMT5939B/TR13 specifies a maximum reverse leakage current (IR) of 900 µA at a reverse voltage (VR) of 29.7 V, measured at TL = 30°C. This low leakage supports stable operation in high-impedance bias networks and battery-powered systems where standby current must be minimized.

Does the 1PMT5939B/TR13 have ESD protection built-in?

Yes, the 1PMT5939B/TR13 is rated for >16 kV electrostatic discharge per the Human Body Model (HBM), providing inherent protection during handling, automated placement, and board-level integration - eliminating the need for external ESD safeguards in most industrial and automotive applications.