Taiwan Semiconductor Corporation KBU803G

Overview

KBU803G from Taiwan Semiconductor is a 8A, 200V repetitive peak reverse voltage (V_RRM) glass-passivated standard bridge rectifier in KBU package, featuring 200A surge current capability, 1.1V max forward voltage at 8A, and <5µA reverse leakage at 25°C - used in AC/DC front-end stages of compact switching mode power supplies.

For engineers reviewing the KBU803G datasheet, KBU803G pinout, KBU803G application, or KBU803G equivalent, key selection criteria include V_RRM = 200V, I_F = 8A, thermal resistance R_θJC = 3°C/W, and UL recognition E-326243 for safety-critical adapter and lighting designs.

Technical Context

The KBU803G integrates four silicon diodes in a single-phase full-wave bridge configuration with quad-terminal layout (AC1, AC2, +, –), enabling direct AC input rectification without external interconnects. Its glass-passivated junction ensures stable reverse characteristics across temperature and long-term reliability under repeated surge stress.

Designed for PCB mounting with matte tin-plated leads compliant to J-STD-002, the device supports high-density layouts and meets JESD201 Class 1A whisker resistance. Thermal performance is defined by R_θJA = 18°C/W (free air) and R_θJC = 3°C/W, enabling effective heat transfer to heatsinks via case contact.

Key Specifications

Pinout & Package

Package: KBU - molded plastic case with integral heatsink tab, UL 94V-0 rated, 7.2g weight, matte tin-plated leads, polarity marked on top surface.

Key Features

Applications

Equivalent & Alternatives

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

Compared with GBU8K and KBPC802, the KBU803G offers optimal balance of 200V rating, thermal efficiency (R_θJC = 3°C/W), and UL-certified reliability for 230V-input SMPS - avoiding over-specification while maintaining margin for surge and aging.

Availability

KBU803G is available at Aetrix Electronics and suitable for switching mode power supplies, LED lighting drivers, and USB-C wall adapters requiring stable component supply, consistent UL certification, and long-term manufacturability.

Supply support for KBU803G 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 power, industrial, and consumer markets since 1979.

The KBU803G belongs to TSC's standard bridge rectifier product line, engineered for cost-effective, high-reliability AC/DC conversion in space- and safety-constrained power supplies.

FAQ

What is the maximum repetitive peak reverse voltage (V_RRM) for KBU803G?

The KBU803G has a V_RRM of 200 V, verified per Taiwan Semiconductor's official datasheet revision J2103. This rating ensures safe operation with 230 V_AC mains input including line surges and transients. The value is laser-marked as "KBU803G" on the device body and confirmed in the Absolute Maximum Ratings table.

Does KBU803G require a heatsink in standard 8A operation?

KBU803G can operate at 8A without an external heatsink under free-air conditions up to ~45°C ambient, based on its R_θJA = 18°C/W. However, for continuous 8A operation above 45°C or in enclosed environments, a heatsink is recommended - especially given its R_θJC = 3°C/W, which enables efficient thermal transfer when mounted to metal chassis or PCB copper planes.

Is KBU803G RoHS compliant and lead-free?

Yes, KBU803G is RoHS compliant and lead-free, as explicitly stated in the "Features" section of the Taiwan Semiconductor datasheet (J2103). Its matte tin-plated leads meet J-STD-002 solderability requirements, and the molding compound complies with UL 94V-0 flammability standards - all verified in the Mechanical Data and Ordering Information sections.

What is the marking code and date code format for KBU803G?

KBU803G is marked with "KBU803G" followed by a date code in YWW format (e.g., "2426" = 2024, week 26) and factory code "F", per the Marking Diagram on page 4 of the J2103 datasheet. The device uses standard KBU package outline with polarity indicated by a cathode bar adjacent to the "+" terminal.

Can KBU803G replace KBU802G in an existing design?

KBU803G can directly replace KBU802G (100V V_RRM) if the application operates at ≤200V reverse stress and board layout accommodates identical KBU footprint and pinout. No circuit changes are needed, but verify that increased V_RRM does not impact snubber design or leakage-sensitive control circuits - particularly in low-voltage auxiliary supplies.