Microchip Technology 1PMT5935/TR7

Overview

1PMT5935B from Microsemi is a 27 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 23 Ω dynamic impedance at 13.9 mA test current and 1 µA max reverse leakage at 20.6 V. It serves as a precision voltage reference or overvoltage clamp in power supply regulation and transient protection circuits.

For engineers reviewing the 1PMT5935B datasheet, 1PMT5935B pinout, 1PMT5935B application, or 1PMT5935B equivalent, key selection criteria include its 27 V nominal Zener voltage, 3.0 W thermal capability with metallic-tab heat sinking, DO-216 mechanical outline, and ESD rating >16 kV HBM - critical for automotive and industrial power rail stabilization.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable voltage across load variations and temperature shifts from –55°C to +150°C. Its full metallic bottom and integral locking tab provide low thermal resistance (30°C/W junction-to-TAB1) and reliable solder joint integrity during reflow.

The device exhibits tight knee characteristics (IZK = 0.25 mA, ZZK = 700 Ω), enabling stable regulation even at low bias currents. Reverse leakage remains ≤1 µA up to 20.6 V, supporting low-power standby circuitry where quiescent current must be minimized.

Key Specifications

Pinout & Package

Package: Powermite® (DO-216AA), molded surface-mount package with full metallic bottom and integral heat-sink locking tab; cathode designated by TAB 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMCJ27A and BZX84-C27, the 1PMT5935B uniquely combines 3.0 W continuous DC power handling, low 23 Ω dynamic impedance, and integrated metallic heat-sink tab - making it suitable for applications demanding both precision regulation and robust thermal performance in compact SMT form.

Availability

1PMT5935B is available at Aetrix Electronics and suitable for automotive power rail clamping, industrial SMPS feedback references, and medical equipment overvoltage protection requiring stable component supply and traceable sourcing.

Supply support for 1PMT5935B 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 series was designed to deliver high-power surface-mount voltage regulation in space-constrained applications where thermal management and assembly reliability are critical - especially in automotive and industrial power systems.

FAQ

What is the Zener voltage tolerance for 1PMT5935B?

The 1PMT5935B has a standard Zener voltage tolerance of ±5% at 27 V, measured at IZT = 13.9 mA and TAB 1 temperature of 30°C. Tighter tolerances of ±2% (suffix C) and ±1% (suffix D) are available upon request. This tolerance directly impacts regulation accuracy in feedback and reference circuits using the 1PMT5935B.

How is thermal performance characterized for 1PMT5935B?

The 1PMT5935B features a thermal resistance of 30°C/W from junction to TAB 1, enabled by its full metallic bottom and integral locking tab. This allows effective heat transfer to the PCB copper pad. Derating is required above 60°C TAB temperature, with full 3.0 W power dissipation only guaranteed at TAB 1 = 60°C - critical for sustained operation in the 1PMT5935B.

Can 1PMT5935B be used in place of through-hole Zener diodes?

Yes, the 1PMT5935B replaces axial-lead or DO-41 Zeners in space-constrained designs, offering identical 27 V regulation but in a surface-mount Powermite® (DO-216AA) package. Its 3.0 W rating matches many 1 W through-hole parts when properly heatsinked via TAB 1, though layout must accommodate its unique two-terminal SMT footprint - unlike traditional leaded parts.

What is the maximum reverse voltage before breakdown for 1PMT5935B?

The 1PMT5935B maintains ≤1 µA reverse leakage up to 20.6 V, defined as the maximum reverse voltage (VR) before entering the Zener breakdown region. Breakdown begins near 27 V (VZ), with full regulation established at IZT = 13.9 mA. Operating below 20.6 V ensures minimal leakage, preserving low-power behavior in the 1PMT5935B.

Is tape-and-reel packaging available for 1PMT5935B?

Yes, the 1PMT5935B is supplied in EIA-481-compliant tape-and-reel packaging: 3,000 pieces per 7-inch reel and 12,000 pieces per 13-inch reel. This format supports automated SMT placement and ensures consistent orientation (cathode marked on TAB 1) - essential for high-yield manufacturing using the 1PMT5935B.