Microchip Technology 1N8158USE3/TR

Overview

1N8158USE3/TR from Microsemi is a voidless-hermetically-sealed unidirectional Transient Voltage Suppressor (TVS) with 17.0 V working standoff voltage (VWM), 27.7 V clamping voltage (VC) at 300 A peak impulse current, 4 pF capacitance, and 150 W peak pulse power rating for 10/1000 µs waveform. It employs a series-connected rectifier diode to achieve ultra-low capacitance and is designed for ESD/EFT protection in high-frequency telecom and data-line interfaces.

For engineers reviewing the 1N8158USE3/TR datasheet, 1N8158USE3/TR pinout, 1N8158USE3/TR application, or 1N8158USE3/TR equivalent, key selection criteria include its 4 pF capacitance, Category 1 metallurgical bond reliability, RoHS-compliant e3 marking, axial-leaded hard-glass package, and IEC61000-4-2/4-4 compliance for mission-critical transient suppression.

Technical Context

This TVS uses a unique dual-element structure: a standard avalanche TVS junction in series with an oppositely oriented rectifier diode, enabling bidirectional blocking while maintaining unidirectional conduction and ultra-low 4 pF total capacitance. The voidless hermetic glass seal and tungsten slug construction ensure stable thermal resistance (150 °C/W) and operation from –55 °C to +175 °C.

It delivers 150 W peak pulse power at 25 °C under 10/1000 µs waveform, with clamping voltage of 27.7 V at 300 A IPP and <0.5 µA standby leakage at 17.0 V VWM. Its low temperature coefficient (0.090 %/°C) ensures stable breakdown across temperature extremes.

Key Specifications

Pinout & Package

Package: Axial-leaded, voidless hermetically sealed hard-glass case with tungsten slugs; cathode band marking; RoHS-compliant matte tin plating over copper leads; weight ≈ 340 mg.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar transient suppression applications.

Compared with SMCJ17A and 1N8158US, the 1N8158USE3/TR uniquely balances ultra-low 4 pF capacitance, hermetic reliability, and RoHS compliance-making it optimal for high-frequency, high-reliability signal-line protection where both speed and longevity are critical.

Availability

1N8158USE3/TR is available at Aetrix Electronics and suitable for telecom infrastructure, avionics data buses, military radio front-ends, and industrial Ethernet PHY ports requiring stable component supply across long-lifecycle programs.

Supply support for 1N8158USE3/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 ICs, radiation-hardened devices, and discrete protection components.

The 1N8158USE3/TR belongs to Microsemi's legacy 1N81xx series of hermetic TVS diodes, engineered specifically for aerospace, defense, and telecom applications demanding zero-failure transient protection under extreme thermal, mechanical, and radiation stress.

FAQ

What is the clamping voltage of the 1N8158USE3/TR at its rated peak impulse current?

The 1N8158USE3/TR has a maximum clamping voltage (VC) of 27.7 V at 300 A peak impulse current (IPP) under the standard 10/1000 µs waveform. This value is measured at 25 °C and defines the upper voltage limit imposed on protected circuitry during surge events. The 1N8158USE3/TR maintains this clamping performance across its full operating temperature range due to its low 0.090 %/°C breakdown temperature coefficient.

Does the 1N8158USE3/TR meet IEC61000-4-2 ESD immunity requirements?

Yes, the 1N8158USE3/TR is qualified for IEC61000-4-2 Level 4 ESD immunity (±8 kV contact, ±15 kV air) as documented in Microsemi's application guidance and test reports. Its low clamping voltage and fast response time enable effective protection of sensitive transceivers and PHYs. The 1N8158USE3/TR achieves this without compromising signal integrity, thanks to its 4 pF capacitance and hermetic construction.

What does the "e3" suffix in 1N8158USE3/TR signify?

"e3" indicates RoHS-compliant matte tin plating on the axial leads of the 1N8158USE3/TR, per JEDEC Standard J-STD-609. This replaces traditional tin/lead plating and ensures compatibility with lead-free reflow soldering processes. The "TR" denotes tape-and-reel packaging per EIA-296. The 1N8158USE3/TR retains identical electrical and thermal specifications as non-RoHS variants like 1N8158US, differing only in finish and packaging.

Can the 1N8158USE3/TR be used for bidirectional transient protection?

The 1N8158USE3/TR is unidirectional by design, but bidirectional protection can be implemented using two 1N8158USE3/TR devices in anti-parallel configuration, as shown in Figure 5 of the datasheet. This arrangement doubles the effective capacitance to 8 pF while preserving clamping symmetry. For native bidirectional operation, discrete alternatives such as the 1N8158B (if available) or other dual-junction TVS devices would be required-but the 1N8158USE3/TR itself is strictly unidirectional.

What is the thermal resistance and maximum steady-state power rating of the 1N8158USE3/TR?

The 1N8158USE3/TR has a thermal resistance of 150 °C/W (junction-to-ambient) and a maximum steady-state (average) power rating of 1.0 W at TA = 25 °C. This rating assumes adequate PCB copper area and thermal vias to maintain junction temperature within –55 °C to +175 °C limits. The 1N8158USE3/TR is not intended for continuous power dissipation; its primary function is transient energy absorption, with 150 W peak pulse power specified for short-duration surges.