Taiwan Semiconductor Corporation TUAS8J

Overview

TUAS8J from Taiwan Semiconductor is a single-die, standard surface-mount rectifier with 600 V repetitive peak reverse voltage (V_RRM), 8 A average forward current (I_F), and low forward voltage drop of 0.96 V at 8 A and 25°C - used in DC-DC converters and switching-mode power supplies for high-efficiency AC/DC and isolated DC/DC stages.

For engineers reviewing the TUAS8J datasheet, TUAS8J pinout, TUAS8J application, or TUAS8J equivalent, key selection criteria include its TO-277A (SMPC4.6U) wettable flank package, 230 A surge rating (t = 8.3 ms), 4 °C/W junction-to-lead thermal resistance, and verified performance across -55°C to +150°C junction temperature range.

Technical Context

The TUAS8J operates as a unidirectional silicon rectifier diode optimized for high-frequency switching applications. Its electrical behavior is defined by a maximum forward voltage of 1.10 V at 8 A and 25°C, reverse leakage current ≤5 µA at 25°C and rated V_RRM, and junction capacitance of 62 pF at 1 MHz and 4.0 V reverse bias.

Thermally, it delivers R_θJL = 4 °C/W and R_θJA = 38 °C/W when mounted on a 16 mm × 16 mm copper pad PCB - enabling reliable operation under continuous 8 A load with appropriate board-level heat spreading.

Key Specifications

Pinout & Package

Package: TO-277A (SMPC4.6U), surface-mount, single-anode/single-cathode configuration with wettable flank leads and cathode band polarity marking.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TUAS8J, STTH8R06DJF offers nearly identical electrical specs but slightly lower thermal performance, while MBR860CT trades surface-mount convenience and manufacturability for legacy through-hole compatibility - making TUAS8J optimal for high-volume, AOI-enabled SMT production.

Availability

TUAS8J is available at Aetrix Electronics and suitable for DC-DC converters, switching-mode inverters, and industrial AC/DC front-end rectification requiring stable component supply, consistent parametric performance, and full RoHS/halogen-free compliance.

Supply support for TUAS8J 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, specializing in power rectifiers, TVS diodes, MOSFETs, and bipolar transistors.

The TUAS8J belongs to TSC's TUAS8x family of standard rectifiers designed specifically for high-efficiency, high-reliability surface-mount power conversion in industrial, computing, and consumer power supplies.

FAQ

What is the peak repetitive reverse voltage rating of the TUAS8J?

The TUAS8J has a peak repetitive reverse voltage (V_RRM) rating of 600 V, confirmed in the Absolute Maximum Ratings table of the official TSC datasheet (Version C2109). This rating defines the maximum reverse-biased voltage the device can block repeatedly without breakdown, making it suitable for 400 VAC-derived DC bus applications with safety margin. The TUAS8J is part of the TUAS8D–TUAS8M series where voltage variants are differentiated by suffix letter.

Does the TUAS8J have wettable flank leads, and why does that matter?

Yes, the TUAS8J features wettable flank leads per its mechanical data and packaging description. This design enables automated optical inspection (AOI) of solder fillets on the side edges of the TO-277A package after reflow, improving process yield and quality control in high-volume SMT lines. The TUAS8J's wettable flank is explicitly cited in the FEATURES section and supported by its J-STD-020 Level 1 moisture sensitivity rating.

What is the forward voltage drop of the TUAS8J at full rated current?

At 8 A forward current and 25°C junction temperature, the TUAS8J exhibits a typical forward voltage (V_F) of 0.96 V, with a maximum of 1.10 V per the Electrical Specifications table. At elevated temperature (125°C), V_F drops to 0.87 V (typ) due to semiconductor physics - an important detail for thermal-aware efficiency modeling. These values are measured under pulse conditions (PW = 0.3 ms) and apply directly to the TUAS8J variant.

Is the TUAS8J RoHS and halogen-free compliant?

Yes, the TUAS8J is RoHS compliant and halogen-free in accordance with IEC 61249-2-21, as stated in the FEATURES section of the official TSC documentation. This compliance is verified for the entire TUAS8D–TUAS8M series, including TUAS8J, and applies to all homogeneous materials in the device - critical for export-controlled and environmentally regulated end equipment.

What is the thermal resistance from junction to lead (R_θJL) for the TUAS8J?

The TUAS8J has a junction-to-lead thermal resistance (R_θJL) of 4 °C/W, specified in the THERMAL PERFORMANCE section. This value is measured with the device mounted on a standard 16 mm × 16 mm copper pad test board and reflects efficient heat transfer from the die to the PCB via the leads - a key advantage over higher-R_θJL alternatives when designing compact, convection-cooled power stages using the TUAS8J.