Microchip Technology 1PMT5944/TR13

Overview

1PMT5944B from Microsemi is a 62 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 100 Ω dynamic impedance at 6.0 mA test current and 1500 µA max reverse leakage at 47.1 V, used for precision voltage regulation in power supply feedback loops and overvoltage protection circuits.

For engineers reviewing the 1PMT5944B datasheet, 1PMT5944B pinout, 1PMT5944B application, or 1PMT5944B equivalent, key selection criteria include zener voltage accuracy, thermal resistance (30°C/W junction-to-TAB), ESD rating (>16 kV HBM), low knee impedance (100 Ω), and compatibility with automated SMT assembly per EIA-481 tape-and-reel packaging.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable reference voltage under varying load and temperature conditions. Its Powermite® package features a full metallic bottom and integral heat sink locking tab, enabling efficient thermal conduction from junction to PCB via TAB 1 - the cathode terminal - with measured thermal resistance of 30°C/W.

The device exhibits tight regulation characteristics: 62 V nominal zener voltage at 6.0 mA (IZT), 100 Ω dynamic impedance (ZZT), and 1500 µA maximum reverse leakage (IR) at 47.1 V (VR). It supports operation across -55°C to +150°C junction temperature range and meets >16 kV human body model ESD immunity.

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; mounting position unrestricted; weight ≈ 0.016 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMCJ64A and BZX84-C62, the 1PMT5944B uniquely delivers precision 62 V regulation at 3.0 W continuous power in a thermally optimized surface-mount package - making it irreplaceable in high-stability, high-power shunt reference applications where both accuracy and thermal performance are required.

Availability

1PMT5944B is available at Aetrix Electronics and suitable for switching power supply feedback, overvoltage protection clamp, and industrial sensor reference applications requiring stable component supply, consistent parametric performance, and long-term manufacturing continuity.

Supply support for 1PMT5944B 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-hardened components for aerospace, defense, and industrial markets.

The Powermite® Zener diode product line was engineered for high-power surface-mount voltage regulation in space-constrained, thermally demanding environments - emphasizing thermal efficiency, assembly robustness, and parametric consistency across temperature.

FAQ

What is the zener voltage tolerance for 1PMT5944B?

The 1PMT5944B has a standard zener voltage tolerance of ±5% at 62 V nominal, measured at 6.0 mA test current with TAB 1 held at 30°C. Tighter tolerances are available: 1PMT5944C (±2%) and 1PMT5944D (±1%), indicated by suffix letters in the part number. Voltage measurement must be performed within 20 seconds of applying DC current to avoid thermal drift effects.

How is thermal management implemented in the 1PMT5944B package?

The 1PMT5944B uses the Powermite® package with TAB 1 as the cathode and primary thermal path. Its 30°C/W junction-to-TAB thermal resistance requires direct soldering of TAB 1 to a copper thermal pad on the PCB. The full metallic bottom and integral locking tab enhance heat transfer and mechanical stability, enabling full 3.0 W power dissipation only when TAB 1 is properly thermally anchored.

Is the 1PMT5944B compatible with standard SMT assembly processes?

Yes, the 1PMT5944B is designed for compatibility with automated SMT assembly. It ships in EIA-481 compliant tape-and-reel format (3,000 pcs per 7″ reel), features a molded surface-mount footprint matching DO-216 mechanical dimensions, and its full metallic bottom eliminates solder flux entrapment - reducing defects and improving first-pass yield in reflow processes.

What is the maximum reverse leakage current for 1PMT5944B and at what voltage is it specified?

The 1PMT5944B specifies a maximum reverse leakage current (IR) of 1500 µA at a reverse voltage (VR) of 47.1 V. This value is measured at TL = 30°C and reflects worst-case leakage under sub-breakdown bias conditions, critical for low-power bias networks where standby current must be minimized.

Does the 1PMT5944B have ESD protection, and what is its rating?

Yes, the 1PMT5944B has an ESD rating exceeding 16 kV per the Human Body Model (HBM), verified per ANSI/ESDA/JEDEC JS-001. This high immunity level ensures robust handling during automated manufacturing, PCB assembly, and field deployment in electrically noisy industrial environments - without requiring additional external ESD protection circuitry.