Taiwan Semiconductor Corporation US1K R3G

Overview

US1K R3G from Taiwan Semiconductor is a 800 V, 1 A ultrafast surface-mount rectifier in DO-214AC (SMA) package, featuring 75 ns reverse recovery time, 1.7 V max forward voltage at 1 A, and 5 µA max reverse leakage at 25°C - deployed in DC-DC snubber and freewheeling circuits for industrial switching power supplies.

For engineers reviewing the US1K R3G datasheet, US1K R3G pinout, US1K R3G application, or US1K R3G equivalent, key selection criteria include repetitive peak reverse voltage (800 V), thermal resistance (R_θJA = 75 °C/W), junction temperature range (–55 to +150 °C), and RoHS/halogen-free compliance for high-reliability embedded power designs.

Technical Context

This discrete ultrafast rectifier uses a glass-passivated single-die silicon junction optimized for high-frequency switching operation. Its 75 ns reverse recovery time and low junction capacitance (10 pF at 1 MHz, 4 V) minimize switching losses in SMPS topologies operating above 100 kHz.

The device supports automated SMT placement with matte tin-plated leads (J-STD-002 compliant) and meets JESD201 Class 2 whisker resistance. Polarity is marked by a cathode band on the DO-214AC body, and moisture sensitivity is rated Level 1 per J-STD-020.

Key Specifications

Pinout & Package

DO-214AC (SMA) surface-mount package: molded epoxy case meeting UL 94V-0, 0.060 g weight, cathode-indicated band, matte tin-plated leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STTH1R08 and MUR108, the US1K R3G offers identical 800 V/1 A rating and DO-214AC compatibility with MUR108, while providing superior moisture robustness (MSL Level 1 vs. Level 1 for both) and lower room-temperature leakage - making it preferred for humid-environment industrial controls.

Availability

US1K R3G is available at Aetrix Electronics and suitable for DC-DC snubbers, industrial freewheeling paths, LED driver secondary rectification, and AC-DC auxiliary supply circuits requiring stable component supply across extended production lifecycles.

Supply support for US1K R3G 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 global industrial, computing, and consumer markets since 1979.

The US1K R3G belongs to TSC's US1x ultrafast rectifier family, engineered specifically for high-efficiency, high-frequency switching power conversion in cost-sensitive yet reliability-critical applications.

FAQ

What is the maximum junction temperature rating for the US1K R3G?

The US1K R3G has a maximum junction temperature (T_J) of +150°C and a minimum of –55°C. This wide operating range allows deployment in industrial environments with ambient temperatures up to +85°C when proper PCB thermal relief is applied. The US1K R3G's R_θJA of 75 °C/W means that at 1 A DC current and 25°C ambient, junction temperature rise is approximately 75°C - keeping total T_J well within limit.

Is the US1K R3G RoHS and halogen-free compliant?

Yes, the US1K R3G is fully RoHS compliant per EU Directive 2011/65/EU and halogen-free per IEC 61249-2-21. These certifications are confirmed in Taiwan Semiconductor's official documentation (Version N2102) and verified through material declarations. The US1K R3G uses bromine-free flame-retardant molding compound meeting UL 94V-0, and its matte tin-plated leads satisfy J-STD-002 solderability requirements.

What does the 'R3G' suffix indicate in US1K R3G?

The 'R3G' suffix in US1K R3G denotes Taiwan Semiconductor's internal packaging and environmental code: 'R' indicates tape-and-reel packaging (7,500 units per reel), '3' specifies green compound (halogen-free), and 'G' identifies the manufacturing site and date-code format. This coding aligns with TSC's ordering convention for the US1x series and is distinct from voltage rating - the 'K' in US1K alone defines 800 V V_RRM.

Can the US1K R3G replace US1J or US1M in an existing design?

The US1K R3G is not a direct replacement for US1J (600 V) or US1M (1000 V) due to its specific 800 V V_RRM rating. Substituting US1K R3G for US1J risks overvoltage failure in 600 V-class systems experiencing transients; replacing US1M with US1K R3G reduces safety margin in 1000 V applications. Always verify system-level peak reverse stress before interchanging US1x variants - the US1K R3G is engineered exclusively for 800 V-rated circuits.

What is the reverse recovery time specification for US1K R3G, and how is it measured?

The US1K R3G has a maximum reverse recovery time (t_rr) of 75 ns, measured under conditions of I_F = 0.5 A, I_R = 1.0 A, and I_rr = 0.25 A, per the manufacturer's test methodology. This value reflects the time required for minority carriers to clear after forward conduction ceases - a critical parameter for minimizing switching loss and EMI in high-frequency converters. The US1K R3G's 75 ns t_rr is confirmed across the full operating temperature range and is consistent with its use in 200–500 kHz SMPS designs.