Taiwan Semiconductor Corporation TUAR4KH

Overview

TUAR4KH from Taiwan Semiconductor is a 4A, 800V fast recovery surface-mount rectifier in TO-277A (SMPC4.6U) package, featuring 500 ns reverse recovery time, 1.13 V forward voltage at 4A/25°C, and AEC-Q101 qualification for automotive power conversion stages.

For engineers reviewing the TUAR4KH datasheet, TUAR4KH pinout, TUAR4KH application, or TUAR4KH equivalent, key selection criteria include its 800V VRRM rating, wettable flank terminals for automated optical inspection, 90A IFSM surge capability, and thermal resistance profile optimized for high-density DC-DC converter layouts.

Technical Context

The TUAR4KH employs a single-die, glass-passivated PN junction with fast recovery characteristics tailored for switching-mode power supplies operating up to 150°C junction temperature. Its 500 ns trr and 24 pF junction capacitance at 1 MHz/4V support efficient high-frequency rectification in automotive lighting and snubber circuits.

Thermal performance is defined by R_θJL = 5.1°C/W and R_θJA = 47°C/W on a 16 mm × 16 mm Cu pad PCB, enabling reliable operation under sustained 4A average forward current with appropriate board-level heat spreading.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with VS-4EYH08-M3 and MUR480RLG, the TUAR4KH uniquely combines AEC-Q101 compliance, wettable flank leads, and balanced trr/VF trade-off-making it optimal for space-constrained, automotive-qualified SMT rectification where reliability and manufacturability are co-prioritized.

Availability

TUAR4KH is available at Aetrix Electronics and suitable for automotive LED drivers, industrial DC-DC converters, and snubber networks requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for TUAR4KH 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 devices, and automotive-qualified components.

The TUAR4xH series was designed specifically for high-reliability automotive power conversion, emphasizing AEC-Q101 compliance, thermal robustness, and SMT manufacturability in TO-277A packaging.

FAQ

What is the peak repetitive reverse voltage rating for TUAR4KH?

The TUAR4KH has a peak repetitive reverse voltage (VRRM) rating of 800 V, verified per datasheet absolute maximum ratings table. This value defines the maximum reverse-biased voltage the device can block repeatedly without breakdown. The TUAR4KH must not be operated beyond this limit in any design, especially in automotive applications subject to load-dump transients. Derating guidelines recommend maintaining ≥20% margin below 800 V in worst-case system conditions.

Is TUAR4KH qualified for automotive use?

Yes, TUAR4KH is explicitly AEC-Q101 qualified per its product documentation, confirming compliance with stress tests including temperature cycling, high-temperature operating life, and unbiased highly accelerated stress testing. This qualification makes TUAR4KH suitable for under-hood and cabin automotive applications such as LED headlamps and body control modules where reliability under thermal and mechanical stress is mandatory.

What is the reverse recovery time of TUAR4KH and how does it affect switching performance?

The TUAR4KH has a reverse recovery time (trr) of 500 ns under specified test conditions (IF = 0.5 A, IR = 1.0 A, Irr = 0.25 A). This parameter directly impacts switching losses in high-frequency converters: longer trr increases diode turn-off loss and EMI generation. In a 250 kHz DC-DC converter, the TUAR4KH's 500 ns trr balances efficiency and cost better than ultra-fast (<100 ns) alternatives while remaining compatible with standard gate-drive timing.

Does TUAR4KH have wettable flank leads and why does that matter?

Yes, TUAR4KH features wettable flank leads per its mechanical data section. These leads extend solderable plating down the vertical sidewall of the TO-277A package, enabling automated optical inspection (AOI) of solder joint quality without requiring X-ray. For high-volume automotive manufacturing, this eliminates manual inspection steps and improves first-pass yield-making TUAR4KH advantageous over non-wettable alternatives like MUR480RLG in SMT lines with AOI capability.

What is the thermal resistance from junction to lead (R_θJL) for TUAR4KH and how should it be used in layout?

The TUAR4KH has a junction-to-lead thermal resistance (R_θJL) of 5.1°C/W, measured with the device mounted on a 16 mm × 16 mm Cu pad. This low value indicates efficient heat transfer from die to PCB copper via the leads. To leverage this, designers must implement generous thermal pads connected to internal ground/power planes using multiple vias-avoiding isolated pads or insufficient copper area, which would degrade actual thermal performance below the 5.1°C/W spec.