Microchip Technology 1PMT5937B/TR7

Overview

1PMT5937B/TR7 from Microsemi is a 33 V, ±5% tolerance surface-mount Zener diode in the Powermite® package, rated for 3.0 W DC power dissipation at TAB 1 temperature of 60°C, with 11.4 mA test current, 33 Ω dynamic impedance, and 1 µA max reverse leakage at 25.1 V. It serves as a precision voltage reference or overvoltage clamp in compact DC power rails and regulator feedback networks.

For engineers reviewing the 1PMT5937B/TR7 datasheet, 1PMT5937B/TR7 pinout, 1PMT5937B/TR7 application, or 1PMT5937B/TR7 equivalent, key selection criteria include its 33 V nominal Zener voltage, 3.0 W thermal capability via metallic tab, DO-216 mechanical outline, ESD rating >16 kV HBM, and compatibility with automated SMT insertion equipment.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable voltage across its terminals under varying load and line conditions. Its Powermite® package integrates a full metallic bottom (TAB 1) as cathode and thermal path, with a locking tab that enhances heat transfer and mechanical retention during reflow.

The device exhibits low knee impedance (800 Ω at IZK = 0.25 mA) and tight voltage regulation-verified at 30°C case temperature with 20-second DC stabilization per Micro Note 202. Reverse leakage remains ≤1 µA up to 25.1 V, supporting low-power standby circuit integrity.

Key Specifications

Pinout & Package

Package: Powermite® (DO-216AA), molded surface-mount package with full metallic bottom (TAB 1) serving as cathode terminal and primary thermal interface. Dimensions comply with DO-216 mechanical standard (all inches ±0.005).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMF33A and BZX84-C33, the 1PMT5937B/TR7 uniquely delivers continuous 3.0 W regulation in a thermally optimized surface-mount package with verified ESD robustness-making it the only option among the three for high-reliability, high-power Zener applications requiring long-term stability.

Availability

1PMT5937B/TR7 is available at Aetrix Electronics and suitable for industrial power supplies, automotive body control modules, medical sensor bias networks, and telecom line card voltage monitors requiring stable component supply and long-lifecycle availability.

Supply support for 1PMT5937B/TR7 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 family-including 1PMT5937B/TR7-is engineered for high-power density voltage regulation in space-constrained, thermally demanding environments where traditional through-hole or low-power SMT Zeners fail.

FAQ

What is the Zener voltage tolerance for 1PMT5937B/TR7?

The 1PMT5937B/TR7 has a standard Zener voltage tolerance of ±5% at 33 V, measured at 11.4 mA test current and TAB 1 temperature of 30°C. Tighter tolerances of ±2% (suffix C) and ±1% (suffix D) are available upon request. Voltage measurement must be performed 20 seconds after applying DC current to ensure thermal stabilization of the 1PMT5937B/TR7 junction.

How is thermal performance managed in the 1PMT5937B/TR7 package?

The 1PMT5937B/TR7 uses a Powermite® package with a full metallic bottom (TAB 1) acting as both cathode and primary thermal interface. Its 30°C/W junction-to-TAB thermal resistance requires soldering TAB 1 to ≥100 mm² of 2-oz copper for full 3.0 W dissipation at 60°C. The integral locking tab enhances mechanical retention and thermal contact during reflow, directly improving reliability versus standard SOD packages.

Can the 1PMT5937B/TR7 be used in automated SMT assembly?

Yes, the 1PMT5937B/TR7 is fully compatible with automated insertion equipment. It is supplied in EIA-481 compliant tape-and-reel format (3,000 pieces per 7-inch reel), features a DO-216AA outline optimized for pick-and-place nozzles, and includes a locking tab that prevents rotation during placement. Its molded body and consistent lead geometry ensure high first-pass yield in high-volume SMT lines using the 1PMT5937B/TR7.

What is the maximum reverse leakage current for 1PMT5937B/TR7?

The maximum reverse leakage current for 1PMT5937B/TR7 is 1 µA at a reverse voltage of 25.1 V (76% of nominal V_Z) and ambient temperature of 30°C. This low leakage supports energy-efficient designs such as battery-powered sensors and always-on monitoring circuits where standby current must remain below 1 µA-ensuring system-level compliance when using the 1PMT5937B/TR7 as a reference or clamp.

Does the 1PMT5937B/TR7 meet industry ESD standards?

Yes, the 1PMT5937B/TR7 is rated for >16 kV per Human Body Model (HBM), exceeding JEDEC JS-001 Class 3A requirements. This robust ESD immunity eliminates the need for additional protection circuitry on board-level inputs or outputs where the 1PMT5937B/TR7 is deployed, reducing BOM count and layout complexity while ensuring reliability during handling, assembly, and field operation.