Microchip Technology 1N5651A/TR

Overview

1N5651A/TR from Microchip Technology is a unidirectional transient voltage suppressor (TVS) diode in a hermetically sealed DO-13 metal package, designed for high-reliability surge protection in aerospace and industrial systems. It features a 45.4 V rated standoff voltage (VWM), 50.4–53.2 V breakdown voltage (V(BR)), 80.5 V maximum clamping voltage (VC) at 18.6 A peak pulse current (IPP), and 1500 W peak pulse power rating at 10/1000 µs waveform.

For engineers reviewing the 1N5651A/TR datasheet, 1N5651A/TR pinout, 1N5651A/TR application, or 1N5651A/TR equivalent, this device is selected for secondary lightning protection per IEC61000-4-5 (12 Ω source impedance, Class 2), ESD/EFT immunity per IEC61000-4-2/-4, and fast-clamp (<100 ps) protection of DC power rails and signal lines in avionics, motor drives, and telecom infrastructure.

Technical Context

The 1N5651A/TR operates as a unidirectional avalanche diode, entering controlled breakdown when transient voltage exceeds its V(BR) threshold to clamp downstream circuitry. Its hermetic DO-13 package ensures stable performance across -55°C to +175°C operating temperature range and inherent radiation hardness per MicroNote 050.

It delivers 1500 W non-repetitive peak pulse power with <100 ps response time, enabling protection against ESD, EFT, and induced transients from inductive switching or RF coupling. Standby leakage remains ≤5 µA at 45.4 V VWM, supporting low-power system monitoring without loading.

Key Specifications

Pinout & Package

Package: DO-13 (DO-202AA), hermetically sealed metal-glass case with cathode connected to case and polarity marked by diode symbol. Tin-lead plated leads, weight ≈1.4 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N5651A/TR, the bulk 1N5651A offers identical protection performance but lacks TR packaging for automated assembly, while SMBJ45A trades hermetic reliability and 1500 W capability for surface-mount convenience and reduced surge margin.

Availability

1N5651A/TR is available at Aetrix Electronics and suitable for aerospace power distribution, industrial motor drive control, telecom base station DC feeds, and railway signaling interface applications requiring stable component supply, long-term obsolescence management, and traceable military-grade sourcing.

Supply support for 1N5651A/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

Microchip Technology (formerly Microsemi) is a global semiconductor company specializing in high-reliability analog, mixed-signal, and radiation-tolerant components for aerospace, defense, and industrial markets.

The 1N56xxA series was developed to deliver MIL-qualified, hermetic transient suppression for mission-critical avionics and infrastructure systems where failure is not an option.

FAQ

What is the clamping voltage of the 1N5651A/TR under a standard 10/1000 µs surge?

The 1N5651A/TR exhibits a maximum clamping voltage (VC) of 80.5 V when subjected to its rated peak pulse current of 18.6 A under a 10/1000 µs waveform. This value is guaranteed per the T4-LDS-0096 Rev. 3 datasheet and defines the upper voltage limit imposed on protected circuitry during surge events. The 1N5651A/TR achieves this clamping performance while maintaining low leakage and high thermal stability in its DO-13 package.

Is the 1N5651A/TR suitable for IEC61000-4-5 Class 2 lightning surge testing?

Yes, the 1N5651A/TR is explicitly rated for IEC61000-4-5 Class 2 secondary lightning protection with a 12 Ω source impedance, as confirmed in the Applications/Benefits section of the official datasheet. Its 1500 W peak pulse power and 80.5 V clamping voltage enable reliable suppression of the 0.5 kA short-circuit surge waveform defined in that class. The 1N5651A/TR's hermetic construction further ensures consistent performance across environmental stress profiles required for certification.

Does the 1N5651A/TR have radiation hardness certification?

Yes, the 1N5651A/TR is inherently radiation hard per Microsemi MicroNote 050, a documented qualification confirming tolerance to total ionizing dose (TID) environments typical of avionics and space applications. This characteristic stems from its DO-13 metal-glass hermetic construction and silicon process, not added shielding or external hardening. The 1N5651A/TR leverages this property in airborne systems where single-event effects and cumulative dose must be mitigated without derating.

What is the standoff voltage (VWM) rating of the 1N5651A/TR, and how does it relate to system voltage?

The 1N5651A/TR has a rated standoff voltage (VWM) of 45.4 V, meaning it remains nonconductive up to this reverse DC or peak AC voltage. Per datasheet Note 1, VWM should equal or exceed the system's maximum continuous operating voltage - for example, it is appropriate for 28 V DC systems with transient headroom. Exceeding VWM risks premature conduction and accelerated wear; the 1N5651A/TR's 5 µA leakage at VWM ensures minimal impact on such systems.

How does the DO-13 package of the 1N5651A/TR differ from plastic TVS diodes in terms of reliability?

The DO-13 package of the 1N5651A/TR is a welded, hermetically sealed metal-glass construction, unlike plastic axial-leaded alternatives. This eliminates moisture permeation, prevents parameter shift over time and temperature, and supports operation from -55°C to +175°C. Plastic packages exhibit higher leakage drift and reduced surge endurance under thermal cycling - critical distinctions for the 1N5651A/TR's use in avionics and industrial control where field failure is unacceptable.