Microchip Technology 1N5354B/TR8

Overview

1N5354B/TR8 from Microsemi is a 5 W axial-leaded silicon Zener diode with nominal regulation voltage of 17 V, ±5% tolerance (B suffix), 70 mA test current (IZT), 2.5 Ω maximum dynamic impedance (ZZ), and 5.8 V maximum voltage regulation (ΔVZ) across 10–50% of IZM. It operates from –65°C to +150°C and is used for precision voltage reference and overvoltage protection in DC power supplies.

For engineers reviewing the 1N5354B/TR8 datasheet, 1N5354B/TR8 pinout, 1N5354B/TR8 application, or 1N5354B/TR8 equivalent, key selection criteria include Zener voltage accuracy, thermal resistance (25 °C/W junction-to-lead), surge current rating (75 A), reverse leakage (≤0.5 µA at 12.2 V), and RoHS-compliant e3 marking compatibility.

Technical Context

This device functions as a two-terminal voltage regulator in reverse-biased mode, maintaining stable output voltage under varying load and line conditions. Its low dynamic impedance (2.5 Ω) and tight ±5% VZ tolerance ensure minimal voltage drift across operating current range (10–50% of IZM = 7.5–37.5 mA).

Designed for through-hole mounting on FR4 PCBs or lead-soldered heat sinking, it delivers 5 W steady-state power at TL < 25°C (3/8″ lead length), derating linearly above that temperature. The cathode band indicates polarity, and operation requires the banded end to be positive relative to the anode.

Key Specifications

Pinout & Package

Package: Axial-leaded T-18 plastic case per JEDEC DO-204AL standard; void-free UL94V-0 epoxy body; tin-lead or RoHS-compliant matte-tin plating; cathode indicated by color band; weight 0.7 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N5354B (bulk) and MMBZ5246B, the 1N5354B/TR8 uniquely combines JEDEC-standard 5 W power handling, axial-leaded manufacturability, and RoHS-compliant e3 marking-making it optimal for industrial power supply designs requiring proven reliability and automated assembly support.

Availability

1N5354B/TR8 is available at Aetrix Electronics and suitable for DC power supply reference, overvoltage clamp circuit, and temperature-stable bias network applications requiring stable component supply and long-term lifecycle support.

Supply support for 1N5354B/TR8 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 timing solutions for aerospace, defense, and industrial markets.

The 1N53xxB series was engineered for ruggedized voltage regulation in harsh-environment power systems, emphasizing thermal robustness, surge resilience, and JEDEC-standard interchangeability across military and commercial applications.

FAQ

What is the Zener voltage tolerance of the 1N5354B/TR8?

The 1N5354B/TR8 has a Zener voltage tolerance of ±5%, as indicated by the "B" suffix in its part number. This means its actual regulation voltage falls within 16.15 V to 17.85 V at 70 mA test current and 25°C lead temperature. This tolerance is tighter than the ±10% offered by "A"-suffix variants and supports precision regulation without the cost premium of ±1% "D"-suffix devices. The 1N5354B/TR8 maintains this specification across its full operating temperature range of –65°C to +150°C.

Can the 1N5354B/TR8 be used in surface-mount designs?

No, the 1N5354B/TR8 is an axial-leaded device in the T-18 (DO-204AL) package and is not compatible with surface-mount assembly. It requires through-hole mounting with 3/8″ (10 mm) lead length from the body for rated 5 W operation. For surface-mount equivalents, Microsemi offers the SMBJ5354B or SMBG5354B in SMB/SMBG packages-but these differ in thermal performance, surge rating, and footprint. The 1N5354B/TR8 must be mounted using wave or hand soldering with appropriate pad layout per IPC-7351 guidelines.

What is the maximum surge current rating for the 1N5354B/TR8?

The 1N5354B/TR8 has a maximum non-repetitive surge current (IZSM) rating of 75 A for an 8.3 ms half-sine waveform, as specified in the Microsemi datasheet. This rating reflects its capability to absorb transient overvoltage events-such as ESD or inductive switching spikes-without parametric shift or failure. To sustain this rating, the device must be mounted with adequate copper pour and thermal relief; derating applies for repeated surges or elevated ambient temperatures. The 1N5354B/TR8 achieves this via low thermal resistance (25 °C/W junction-to-lead) and robust silicon construction.

How does the 1N5354B/TR8 handle reverse leakage current?

The 1N5354B/TR8 specifies a maximum reverse leakage current (IR) of 0.5 µA at a reverse test voltage (VR) of 12.2 V-well below its 17 V Zener voltage. This ultra-low leakage ensures minimal power loss in high-impedance reference networks and preserves accuracy in precision bias circuits. The leakage remains stable across temperature due to the device's moisture-insensitive Level 1 classification and thermosetting epoxy encapsulation. At 125°C, IR increases only marginally, staying under 2.0 µA, making the 1N5354B/TR8 suitable for extended-temperature industrial applications.

Is the 1N5354B/TR8 RoHS compliant?

Yes, the 1N5354B/TR8 is RoHS compliant, as confirmed by the "e3" suffix in its full manufacturer marking and documentation. This indicates lead-free matte-tin plating on the leads and compliance with EU Directive 2011/65/EU and China RoHS II. The device meets JEDEC J-STD-020B moisture sensitivity Level 1, eliminating the need for dry packing or baking before soldering. All materials-including the UL94V-0 epoxy body-are screened for restricted substances, and full compliance documentation is available from Microchip Technology (which acquired Microsemi) upon request.