Taiwan Semiconductor Corporation KBL604G

Overview

KBL604G from Taiwan Semiconductor is a 6A, 400V repetitive peak reverse voltage (V_RRM) standard bridge rectifier in KBL package, featuring glass-passivated junctions and matte tin-plated leads. It delivers 175A non-repetitive surge current handling, 7.5°C/W junction-to-lead thermal resistance, and operates across –55°C to +150°C junction temperature range. Used in AC/DC front-end stages of compact power adapters.

For engineers reviewing the KBL604G datasheet, KBL604G pinout, KBL604G application, or KBL604G equivalent, key selection criteria include V_RRM = 400V, I_F = 6A, I_FSM = 175A, R_θJL = 7.5°C/W, and UL recognition per File # E-326243 - all critical for thermal reliability and safety compliance in space-constrained SMPS designs.

Technical Context

The KBL604G integrates four silicon diodes in a single-phase full-wave bridge configuration with common-cathode and common-anode terminals externally accessible. Its glass-passivated junction ensures stable reverse leakage (<10 µA at 25°C) and robustness against humidity and contamination during PCB assembly.

Thermally, it relies on lead-frame conduction via the KBL package's 4-pin layout, achieving 7.5°C/W junction-to-lead resistance - enabling direct heatsinking through PCB copper pours or optional clip-on heatsinks without requiring isolated mounting hardware.

Key Specifications

Pinout & Package

Package: KBL - molded plastic body (19.5 × 15.2 × 16.3 mm), UL 94V-0 rated, with 4 matte tin-plated leads (2 AC inputs, 1 +DC, 1 –DC), 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 GBU6K and W04M, the KBL604G provides superior thermal performance in constrained spaces and certified safety compliance - making it optimal for high-volume, regulated power supplies where reliability, certification speed, and thermal margin are prioritized over minimal footprint.

Availability

KBL604G is available at Aetrix Electronics and suitable for switching mode power supplies, USB-C adapters, and industrial control power modules requiring stable component supply, consistent parametric performance, and UL-recognized safety assurance.

Supply support for KBL604G 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 KBL604G belongs to TSC's standard bridge rectifier product line, engineered for cost-effective, high-reliability AC/DC conversion in consumer and industrial power supplies where safety certification, thermal stability, and long-term supply continuity are essential.

FAQ

What is the maximum repetitive peak reverse voltage (V_RRM) rating for KBL604G?

The KBL604G has a V_RRM rating of 400 V, confirmed in the Absolute Maximum Ratings table of Taiwan Semiconductor's H2308 datasheet. This value defines the highest instantaneous reverse voltage the device can block repeatedly without avalanche breakdown. It corresponds to an AC input RMS voltage limit of approximately 283 V, making KBL604G suitable for universal-input (90–264 V_AC) power supplies. Exceeding this rating risks irreversible junction failure.

Does KBL604G require a heatsink in typical 6 A operation?

KBL604G does not require an external heatsink under typical conditions if PCB copper area is optimized: its R_θJL = 7.5°C/W allows junction temperature rise of ~45°C above lead temperature at 6 A (assuming 1.1 V V_F). With ≥25 cm² of 2-oz copper connected to both +DC and –DC leads, and ambient ≤50°C, T_J stays below 125°C. For sustained 6 A in >60°C ambient, a small clip-on heatsink is recommended. The KBL604G datasheet provides derating curves confirming this behavior.

Is KBL604G RoHS compliant and lead-free solderable?

Yes, KBL604G is RoHS compliant and features matte tin-plated leads qualified per IPC J-STD-002 for both reflow and wave soldering. The datasheet explicitly states "RoHS Compliant" and "solderable per J-STD-002", and the leads pass JESD 201 Class 1A whisker testing. No special solder profile or pre-tinning is needed - standard Pb-free reflow profiles (peak 245°C, 60–90 sec above 220°C) achieve reliable wetting and joint integrity with KBL604G.

What is the marking code on the KBL604G package?

The top surface of the KBL604G package is laser-marked with "KBL604G" as the full part number, followed by a date code (YWW format, e.g., "2428" for week 28 of 2024) and factory code (e.g., "F"). This marking matches the ordering code defined in the datasheet's Ordering Information section and enables traceability to wafer lot and assembly batch. No abbreviated or alternate markings are used - verification requires visual inspection of the actual device body.

How does KBL604G compare to KBL606G in terms of voltage rating and interchangeability?

KBL604G has V_RRM = 400 V, while KBL606G is rated for 800 V - they are not interchangeable without circuit review. Substituting KBL606G for KBL604G adds unnecessary cost and may degrade thermal performance due to higher forward voltage (1.2 V typ. at 6 A). Using KBL604G in place of KBL606G risks catastrophic failure if peak reverse voltage exceeds 400 V. Always match V_RRM to the worst-case AC input condition; KBL604G is validated only for ≤400 V applications per Taiwan Semiconductor's specification.