Microchip Technology 1N4743CE3/TR13

Overview

1N4743CE3/TR13 from Microsemi is a 13 V, 5% tolerance, 1 W silicon Zener diode in DO-41 plastic package, rated for 19 mA test current (IZT), 10 Ω dynamic impedance (ZZT), and 0.25 A maximum regulator current (IZM) at 50°C. It provides stable voltage regulation in power supply reference and overvoltage protection circuits across industrial temperature range.

For engineers reviewing the 1N4743CE3/TR13 datasheet, 1N4743CE3/TR13 pinout, 1N4743CE3/TR13 application, or 1N4743CE3/TR13 equivalent, key selection criteria include Zener voltage tolerance (±5%), thermal resistance (45°C/W junction-to-lead), surge current rating (344 mA), RoHS-compliant matte-tin plating, and tape-and-reel packaging (TR13).

Technical Context

This discrete Zener diode operates in reverse breakdown to maintain a stable 13 V reference across load and line variations. Its 19 mA test current ensures low dynamic impedance (10 Ω), while its 0.25 A IZM supports moderate regulation current without thermal runaway under transient conditions.

Designed for axial-lead mounting on FR4 PCBs with 4 mm² copper pads, it delivers 1 W dissipation at lead temperature <105°C or ambient <45°C. The cathode band marking and polarity-sensitive operation require correct orientation for regulation-banded end must be positive relative to the anode.

Key Specifications

Pinout & Package

DO-41 (DO-204AL) plastic axial-leaded package with cathode indicated by color band; terminals are unmarked anode and banded cathode.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N4743A and MMBZ5242BS, the 1N4743CE3/TR13 uniquely combines RoHS compliance, 1 W power rating, DO-41 mechanical robustness, and tape-and-reel automation support-making it optimal for industrial power supply and protection modules requiring long-term supply continuity and thermal reliability.

Availability

1N4743CE3/TR13 is available at Aetrix Electronics and suitable for industrial power supplies, overvoltage protection circuits, and voltage reference designs requiring stable component supply, consistent parametric performance, and RoHS-compliant manufacturing.

Supply support for 1N4743CE3/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 and mixed-signal components for aerospace, defense, and industrial markets.

The 1N47xxA Zener series was designed for precision voltage regulation in mission-critical power systems where stability, temperature resilience, and long-term parameter consistency are required.

FAQ

What is the Zener voltage tolerance of the 1N4743CE3/TR13?

The 1N4743CE3/TR13 has a nominal Zener voltage of 13 V with a tolerance of ±5%, as confirmed by the "C" suffix in the part number per Microsemi's documentation. This tolerance applies at 19 mA test current and 25°C lead temperature. The 1N4743CE3/TR13 maintains this specification across its full operating temperature range of –65°C to +150°C, making it suitable for applications demanding stable reference accuracy under thermal stress.

Does the 1N4743CE3/TR13 support lead-free assembly?

Yes, the 1N4743CE3/TR13 supports lead-free assembly. The "e3" suffix explicitly denotes RoHS-compliant matte-tin plating, qualified for reflow soldering up to 260°C for 10 seconds per MIL-STD-750 Method 2026. Its moisture sensitivity level is IPC/JEDEC J-STD-020B Level 1, eliminating dry-pack requirements and enabling immediate use after opening-critical for high-throughput SMT lines handling the 1N4743CE3/TR13.

What is the maximum surge current rating for the 1N4743CE3/TR13?

The 1N4743CE3/TR13 has a maximum surge current (ISM) rating of 344 mA, measured using a ½ sine-wave pulse of 1/120 second duration at 25°C ambient. This value is derived from the 13 V Zener voltage and 0.25 A steady-state IZM rating, and reflects the device's ability to absorb short-duration overvoltage events without degradation-essential for protecting downstream circuitry in power supply and interface applications using the 1N4743CE3/TR13.

How is polarity marked on the 1N4743CE3/TR13?

The 1N4743CE3/TR13 uses a cathode band for polarity identification: the banded end is the cathode and must be connected to the higher-potential node for proper Zener regulation. When operated in reverse breakdown, the cathode remains positive relative to the anode. This marking is visible on the DO-41 plastic body and aligns with JEDEC standard orientation-ensuring correct placement during manual or automated assembly of the 1N4743CE3/TR13.

What thermal derating applies to the 1N4743CE3/TR13?

The 1N4743CE3/TR13 is rated for 1.0 W dissipation at 25°C, with linear derating to zero at 150°C junction temperature. Derating follows two paths: 45°C/W junction-to-lead (for 3/8" lead length) or 105°C/W junction-to-ambient on FR4 board (1 oz Cu, 4 mm² pad). At 50°C ambient, its usable power drops to ~0.76 W-directly impacting sustained current capability in the 1N4743CE3/TR13's regulation zone.