Microchip Technology 1N5371E3/TR13

Overview

1N5371E3/TR13 from Microsemi is a 5 W axial-leaded silicon Zener diode with nominal regulation voltage of 60 V, ±5% tolerance (B-suffix equivalent), 20 mA test current, 40 Ω maximum dynamic impedance at IZT, and 350 A peak surge current rating. It operates from –65 °C to +150 °C and is used for precision voltage reference and overvoltage protection in industrial power supplies.

For engineers reviewing the 1N5371E3/TR13 datasheet, 1N5371E3/TR13 pinout, 1N5371E3/TR13 application, or 1N5371E3/TR13 equivalent, key selection criteria include Zener voltage accuracy, thermal resistance (25 °C/W junction-to-lead), steady-state power derating on FR4, reverse leakage at VR = 45.5 V, and RoHS-compliant matte-tin plating per MIL-STD-750.

Technical Context

This device functions as a two-terminal voltage regulator operating in reverse breakdown mode. Its Zener voltage is specified at 20 mA (IZT) with 40 Ω dynamic impedance (ZZ), and it maintains regulation across 10–50% of IZM (350 mA), yielding ≤2.2 V voltage regulation (ΔVZ). The cathode band denotes polarity, requiring the banded end to be biased positive relative to the anode.

Thermal performance is defined for two mounting conditions: 25 °C/W junction-to-lead at 10 mm lead length, and 85 °C/W junction-to-ambient on FR4 with 4 mm² copper pads. Forward voltage is ≤1.2 V at 1.0 A, and surge capability is rated per 8.3 ms half-sine waveform per JEDEC standards.

Key Specifications

Pinout & Package

Package: Axial-leaded T-18 plastic case per JEDEC DO-201AD; void-free UL94V-0 epoxy body; matte-tin plated leads solderable per MIL-STD-750 Method 2026; cathode indicated by single black band.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N5371B and MMSZ5257ET1G, the 1N5371E3/TR13 uniquely combines RoHS compliance, 5 W dissipation, axial-leaded mechanical robustness, and JEDEC-standardized mounting - making it the sole option for high-reliability, through-hole, high-power Zener regulation in industrial environments.

Availability

1N5371E3/TR13 is available at Aetrix Electronics and suitable for industrial power supplies, telecom line protection, programmable bias networks, and sensor excitation circuits requiring stable component supply and long-term obsolescence management.

Supply support for 1N5371E3/TR13 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, RF, and radiation-hardened components for aerospace, defense, and industrial markets.

The 1N53xx series was designed specifically for high-stability, high-power voltage regulation in harsh-environment power systems - emphasizing thermal robustness, surge immunity, and long-term parametric consistency.

FAQ

What is the Zener voltage tolerance of the 1N5371E3/TR13?

The 1N5371E3/TR13 has a nominal Zener voltage of 60 V with ±5% tolerance, consistent with the B-suffix designation in the 1N5333B–1N5388B family. This tolerance is confirmed in Microsemi's REV D datasheet, where the e3 suffix denotes RoHS compliance but retains the same electrical specifications-including tolerance-as the 1N5371B variant.

How does thermal derating work for the 1N5371E3/TR13 on a standard FR4 PCB?

When mounted on FR4 with 4 mm² copper pads and 1 mm trace width, the 1N5371E3/TR13 has a junction-to-ambient thermal resistance of 85 °C/W. Its steady-state power drops from 5.0 W at 25 °C ambient to 1.47 W at 25 °C ambient per Microsemi's Figure 1 derating curve - meaning usable power decreases linearly above 25 °C ambient, reaching zero at approximately 85 °C ambient.

Can the 1N5371E3/TR13 be used as a direct replacement for the 1N5371B?

Yes - the 1N5371E3/TR13 is functionally identical to the 1N5371B in all electrical and mechanical parameters except plating: the e3 suffix indicates RoHS-compliant matte-tin leads versus tin-lead on the 1N5371B. Both share the same T-18 package, 60 V Zener voltage, ±5% tolerance, 5 W rating, and JEDEC registration, enabling drop-in replacement in RoHS-compliant assemblies.

What is the maximum reverse leakage current for the 1N5371E3/TR13, and at what test voltage?

The maximum reverse leakage current for the 1N5371E3/TR13 is 0.5 μA, measured at a reverse test voltage (V_R) of 45.5 V - which corresponds to 76% of its nominal 60 V Zener voltage. This value is specified in the "MAXIMUM REVERSE CURRENT (I_R)" column for B-suffix devices in the Electrical Characteristics table on page 2 of the Microsemi datasheet.

Is the 1N5371E3/TR13 suitable for surge protection in AC mains-connected equipment?

The 1N5371E3/TR13 is rated for 350 A peak surge current (I_ZSM) under an 8.3 ms half-sine waveform, per JEDEC standards. While it can clamp fast transients, its 60 V standoff makes it unsuitable for direct AC mains (e.g., 120/230 V RMS) protection. It is appropriate for secondary-side surge suppression - such as on 48 V telecom lines or DC bus rails - where clamping voltage and energy absorption match system requirements.