Taiwan Semiconductor Corporation KBU1003G

Overview

KBU1003G from Taiwan Semiconductor is a 10A, 200V repetitive peak reverse voltage (VRRM) standard bridge rectifier in KBU package, featuring glass-passivated junctions, <1.1V forward voltage at 10A/25°C, and 200A surge capability - used in AC/DC front-end stages of offline SMPS and LED drivers.

For engineers reviewing the KBU1003G datasheet, KBU1003G pinout, KBU1003G application, or KBU1003G equivalent, key selection criteria include VRRM rating, thermal resistance (RθJC = 2.2°C/W), IFSM derating, UL recognition (E-326243), and RoHS-compliant matte tin-plated leads.

Technical Context

The KBU1003G integrates four silicon diodes in a single-phase full-wave bridge configuration with quad internal layout. Its glass-passivated junction ensures stable leakage performance (<5 µA @ 25°C, <500 µA @ 125°C) and high reliability under thermal cycling.

Designed for PCB mounting with UL 94V-0 molding compound and JESD201 Class 1A whisker resistance, it supports 0.56 N·m maximum mounting torque and operates across -55°C to +150°C junction temperature range.

Key Specifications

Pinout & Package

Package: KBU - molded plastic case with 4 axial leads (AC1, AC2, +, –), UL 94V-0 rated, 7.2 g weight, matte tin-plated for solderability per J-STD-002.

Key Features

Applications

Equivalent & Alternatives

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

Compared with GBU10K and W10M, the KBU1003G offers optimal balance of 200 V rating, UL recognition, 2.2°C/W thermal path, and proven reliability in certified SMPS - making it preferred for volume production of CE/UL-marked consumer and industrial power supplies.

Availability

KBU1003G is available at Aetrix Electronics and suitable for switching mode power supplies, LED lighting drivers, and industrial AC adapters requiring stable component supply and long-term BOM continuity.

Supply support for KBU1003G 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, automotive, and industrial markets since 1979.

The KBU series was developed specifically for high-reliability, high-surge AC/DC front-end rectification in certified offline power supplies - emphasizing UL recognition, thermal robustness, and long-life stability under thermal cycling.

FAQ

What is the peak repetitive reverse voltage (VRRM) rating of the KBU1003G?

The KBU1003G has a VRRM rating of 200 V, meaning it reliably blocks up to 200 V of repetitive reverse voltage across its terminals without breakdown. This rating is validated per JEDEC standards and aligns with its marking code "1003" (where "03" indicates 200 V). The KBU1003G must not be operated beyond this voltage in continuous or repetitive conditions.

Does the KBU1003G require a heatsink for 10 A continuous operation?

Yes - while the KBU1003G has a low RθJC of 2.2°C/W, its RθJA is 25°C/W. At 10 A with typical VF ≈ 1.1 V, power dissipation reaches ~11 W, raising junction temperature significantly without heatsinking. A heatsink or substantial copper pour is required to maintain TJ ≤ 150°C in continuous operation, especially above 60°C ambient.

Is the KBU1003G UL recognized, and what is its file number?

Yes, the KBU1003G is UL Recognized under File # E-326243. This certification covers the entire KBU1001G–KBU1007G family and confirms compliance with UL 60747-4 for semiconductor devices. It validates dielectric strength, flammability (UL 94V-0), and construction integrity - essential for end-product safety approvals.

What is the maximum mounting torque specification for the KBU1003G leads?

The KBU1003G specifies a maximum mounting torque of 0.56 N·m for mechanical fastening (e.g., when securing with screws or clamps). Exceeding this value risks cracking the molded KBU package or damaging internal wire bonds. This value is defined in the Mechanical Data section of the official Taiwan Semiconductor datasheet (Version J2103).

How does the KBU1003G's reverse leakage current change with temperature?

The KBU1003G exhibits IR ≤ 5 µA at 25°C and ≤ 500 µA at 125°C under rated reverse voltage. This 100× increase reflects intrinsic silicon behavior and must be accounted for in high-temperature, high-impedance hold-up circuits. The datasheet confirms this using 30 ms pulse testing per Note 2, ensuring realistic worst-case leakage modeling.