Taiwan Semiconductor Corporation 1N5818

Overview

1N5818 from Taiwan Semiconductor is a 1 A, 30 V Schottky barrier rectifier in DO-41 package, featuring 0.55 V forward voltage at 1 A and 30 A surge capability, used in DC-DC converters and switching power supplies where low conduction loss and fast recovery are critical.

For engineers reviewing the 1N5818 datasheet, 1N5818 pinout, 1N5818 application, or 1N5818 equivalent, key selection factors include its 30 V repetitive peak reverse voltage, 0.55 V typical forward drop at 1 A, 125 °C max junction temperature, DO-41 mechanical outline, and cathode-band polarity marking.

Technical Context

The 1N5818 operates as a single-die, unidirectional Schottky rectifier with metal–semiconductor junction enabling fast switching (no minority-carrier storage) and low forward voltage. Its 10,000 V/µs dv/dt rating supports reliable operation in high-frequency SMPS topologies.

Thermally, it exhibits 100 °C/W junction-to-ambient resistance and 45 °C/W junction-to-case resistance under standard mounting conditions, with derating required above 25 °C ambient to maintain ≤125 °C junction temperature at full 1 A DC current.

Key Specifications

Pinout & Package

Package: DO-204AL (DO-41), axial leaded, epoxy-molded case with cathode band marking polarity. Leads are pure tin-plated, solderable per J-STD-002, UL 94V-0 rated.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Schottky rectifier applications.

Compared with 1N5817 and 1N5819, the 1N5818 provides optimal balance of 30 V reverse margin and 0.55 V forward drop for 24 V input SMPS, avoiding overdesign penalty of 1N5819 while offering greater safety margin than 1N5817 in variable-line applications.

Availability

1N5818 is available at Aetrix Electronics and suitable for AC-DC adapters, DC-DC converters, and switching power supplies requiring stable component supply, consistent DO-41 form factor, and AEC-Q101-qualified variants (1N5818H).

Supply support for 1N5818 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

Taiwan Semiconductor Corporation (TSC) is a vertically integrated analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, serving industrial, computing, and consumer markets since 1979.

The 1N5817–1N5819 series belongs to TSC's general-purpose Schottky rectifier product line, engineered for cost-sensitive, high-volume power conversion applications demanding reliability, thermal stability, and standardized through-hole packaging.

FAQ

What is the maximum repetitive peak reverse voltage (VRRM) for the 1N5818?

The 1N5818 has a VRRM of 30 V, meaning it can safely block up to 30 V of reverse voltage repeatedly without breakdown. This value is specified in the Absolute Maximum Ratings table and is distinct from the 20 V rating of the 1N5817 and 40 V of the 1N5819. Exceeding 30 V risks irreversible avalanche failure in the 1N5818.

What is the forward voltage drop (VF) of the 1N5818 at 1 A and 25 °C?

The 1N5818 exhibits a maximum forward voltage of 0.55 V at 1 A DC and 25 °C junction temperature, per the Electrical Specifications table. This value is measured under pulsed conditions (0.3 ms pulse width) and represents worst-case conduction loss-actual VF decreases slightly at lower currents and increases with rising temperature.

Does the 1N5818 have AEC-Q101 qualification?

Yes-the base 1N5818 is qualified to AEC-Q101 when ordered as 1N5818H (as noted in Ordering Information). Standard 1N5818 devices are not automatically AEC-Q101 qualified; the "H" suffix denotes automotive-grade screening and testing. Always verify the full ordering code to confirm qualification status for automotive use cases.

What package type does the 1N5818 use, and how is polarity identified?

The 1N5818 uses the DO-204AL (DO-41) axial-leaded package. Polarity is indicated by a visible cathode band near one lead end; that banded lead is the cathode terminal. The device weighs approximately 0.330 g and features pure tin-plated leads compliant with J-STD-002 solderability requirements.

What is the junction-to-ambient thermal resistance (RθJA) of the 1N5818?

The 1N5818 has a typical RθJA of 100 °C/W under standard test conditions (JEDEC low-effective-volume board). This value assumes no added heatsinking and defines the temperature rise above ambient per watt of dissipated power-for example, 0.55 W loss at 1 A yields ~55 °C rise above ambient. Derating curves in the datasheet must be followed for operation above 25 °C.